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Asymptotics of PDE in random environment by paracontrolled calculus. (arXiv:2005.03326v1 [math.PR])

We apply the paracontrolled calculus to study the asymptotic behavior of a certain quasilinear PDE with smeared mild noise, which originally appears as the space-time scaling limit of a particle system in random environment on one dimensional discrete lattice. We establish the convergence result and show a local in time well-posedness of the limit stochastic PDE with spatial white noise. It turns out that our limit stochastic PDE does not require any renormalization. We also show a comparison theorem for the limit equation.




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On the Incomparability of Systems of Sets of Lengths. (arXiv:2005.03316v1 [math.AC])

Let $H$ be a Krull monoid with finite class group $G$ such that every class contains a prime divisor. We consider the system $mathcal L (H)$ of all sets of lengths of $H$ and study when $mathcal L (H)$ contains or is contained in a system $mathcal L (H')$ of a Krull monoid $H'$ with finite class group $G'$, prime divisors in all classes and Davenport constant $mathsf D (G')=mathsf D (G)$. Among others, we show that if $G$ is either cyclic of order $m ge 7$ or an elementary $2$-group of rank $m-1 ge 6$, and $G'$ is any group which is non-isomorphic to $G$ but with Davenport constant $mathsf D (G')=mathsf D (G)$, then the systems $mathcal L (H)$ and $mathcal L (H')$ are incomparable.




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Optimality for the two-parameter quadratic sieve. (arXiv:2005.03162v1 [math.NT])

We study the two-parameter quadratic sieve for a general test function. We prove, under some very general assumptions, that the function considered by Barban and Vehov [BV68] and Graham [Gra78] for this problem is optimal up to the second-order term. We determine that second-order term explicitly.




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Continuous speech separation: dataset and analysis. (arXiv:2001.11482v3 [cs.SD] UPDATED)

This paper describes a dataset and protocols for evaluating continuous speech separation algorithms. Most prior studies on speech separation use pre-segmented signals of artificially mixed speech utterances which are mostly emph{fully} overlapped, and the algorithms are evaluated based on signal-to-distortion ratio or similar performance metrics. However, in natural conversations, a speech signal is continuous, containing both overlapped and overlap-free components. In addition, the signal-based metrics have very weak correlations with automatic speech recognition (ASR) accuracy. We think that not only does this make it hard to assess the practical relevance of the tested algorithms, it also hinders researchers from developing systems that can be readily applied to real scenarios. In this paper, we define continuous speech separation (CSS) as a task of generating a set of non-overlapped speech signals from a extit{continuous} audio stream that contains multiple utterances that are emph{partially} overlapped by a varying degree. A new real recorded dataset, called LibriCSS, is derived from LibriSpeech by concatenating the corpus utterances to simulate a conversation and capturing the audio replays with far-field microphones. A Kaldi-based ASR evaluation protocol is also established by using a well-trained multi-conditional acoustic model. By using this dataset, several aspects of a recently proposed speaker-independent CSS algorithm are investigated. The dataset and evaluation scripts are available to facilitate the research in this direction.




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Maximal Closed Set and Half-Space Separations in Finite Closure Systems. (arXiv:2001.04417v2 [cs.AI] UPDATED)

Several problems of artificial intelligence, such as predictive learning, formal concept analysis or inductive logic programming, can be viewed as a special case of half-space separation in abstract closure systems over finite ground sets. For the typical scenario that the closure system is given via a closure operator, we show that the half-space separation problem is NP-complete. As a first approach to overcome this negative result, we relax the problem to maximal closed set separation, give a greedy algorithm solving this problem with a linear number of closure operator calls, and show that this bound is sharp. For a second direction, we consider Kakutani closure systems and prove that they are algorithmically characterized by the greedy algorithm. As a first special case of the general problem setting, we consider Kakutani closure systems over graphs, generalize a fundamental characterization result based on the Pasch axiom to graph structured partitioning of finite sets, and give a sufficient condition for this kind of closures systems in terms of graph minors. For a second case, we then focus on closure systems over finite lattices, give an improved adaptation of the greedy algorithm for this special case, and present two applications concerning formal concept and subsumption lattices. We also report some experimental results to demonstrate the practical usefulness of our algorithm.




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A Shift Selection Strategy for Parallel Shift-Invert Spectrum Slicing in Symmetric Self-Consistent Eigenvalue Computation. (arXiv:1908.06043v2 [math.NA] UPDATED)

The central importance of large scale eigenvalue problems in scientific computation necessitates the development of massively parallel algorithms for their solution. Recent advances in dense numerical linear algebra have enabled the routine treatment of eigenvalue problems with dimensions on the order of hundreds of thousands on the world's largest supercomputers. In cases where dense treatments are not feasible, Krylov subspace methods offer an attractive alternative due to the fact that they do not require storage of the problem matrices. However, demonstration of scalability of either of these classes of eigenvalue algorithms on computing architectures capable of expressing massive parallelism is non-trivial due to communication requirements and serial bottlenecks, respectively. In this work, we introduce the SISLICE method: a parallel shift-invert algorithm for the solution of the symmetric self-consistent field (SCF) eigenvalue problem. The SISLICE method drastically reduces the communication requirement of current parallel shift-invert eigenvalue algorithms through various shift selection and migration techniques based on density of states estimation and k-means clustering, respectively. This work demonstrates the robustness and parallel performance of the SISLICE method on a representative set of SCF eigenvalue problems and outlines research directions which will be explored in future work.




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Space-Efficient Vertex Separators for Treewidth. (arXiv:1907.00676v3 [cs.DS] UPDATED)

For $n$-vertex graphs with treewidth $k = O(n^{1/2-epsilon})$ and an arbitrary $epsilon>0$, we present a word-RAM algorithm to compute vertex separators using only $O(n)$ bits of working memory. As an application of our algorithm, we give an $O(1)$-approximation algorithm for tree decomposition. Our algorithm computes a tree decomposition in $c^k n (log log n) log^* n$ time using $O(n)$ bits for some constant $c > 0$.

We finally use the tree decomposition obtained by our algorithm to solve Vertex Cover, Independent Set, Dominating Set, MaxCut and $3$-Coloring by using $O(n)$ bits as long as the treewidth of the graph is smaller than $c' log n$ for some problem dependent constant $0 < c' < 1$.




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Parameterised Counting in Logspace. (arXiv:1904.12156v3 [cs.LO] UPDATED)

Stockhusen and Tantau (IPEC 2013) defined the operators paraW and paraBeta for parameterised space complexity classes by allowing bounded nondeterminism with multiple read and read-once access, respectively. Using these operators, they obtained characterisations for the complexity of many parameterisations of natural problems on graphs.

In this article, we study the counting versions of such operators and introduce variants based on tail-nondeterminism, paraW[1] and paraBetaTail, in the setting of parameterised logarithmic space. We examine closure properties of the new classes under the central reductions and arithmetic operations. We also identify a wide range of natural complete problems for our classes in the areas of walk counting in digraphs, first-order model-checking and graph-homomorphisms. In doing so, we also see that the closure of #paraBetaTail-L under parameterised logspace parsimonious reductions coincides with #paraBeta-L. We show that the complexity of a parameterised variant of the determinant function is #paraBetaTail-L-hard and can be written as the difference of two functions in #paraBetaTail-L for (0,1)-matrices. Finally, we characterise the new complexity classes in terms of branching programs.




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The Zhou Ordinal of Labelled Markov Processes over Separable Spaces. (arXiv:2005.03630v1 [cs.LO])

There exist two notions of equivalence of behavior between states of a Labelled Markov Process (LMP): state bisimilarity and event bisimilarity. The first one can be considered as an appropriate generalization to continuous spaces of Larsen and Skou's probabilistic bisimilarity, while the second one is characterized by a natural logic. C. Zhou expressed state bisimilarity as the greatest fixed point of an operator $mathcal{O}$, and thus introduced an ordinal measure of the discrepancy between it and event bisimilarity. We call this ordinal the "Zhou ordinal" of $mathbb{S}$, $mathfrak{Z}(mathbb{S})$. When $mathfrak{Z}(mathbb{S})=0$, $mathbb{S}$ satisfies the Hennessy-Milner property. The second author proved the existence of an LMP $mathbb{S}$ with $mathfrak{Z}(mathbb{S}) geq 1$ and Zhou showed that there are LMPs having an infinite Zhou ordinal. In this paper we show that there are LMPs $mathbb{S}$ over separable metrizable spaces having arbitrary large countable $mathfrak{Z}(mathbb{S})$ and that it is consistent with the axioms of $mathit{ZFC}$ that there is such a process with an uncountable Zhou ordinal.




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Brain-like approaches to unsupervised learning of hidden representations -- a comparative study. (arXiv:2005.03476v1 [cs.NE])

Unsupervised learning of hidden representations has been one of the most vibrant research directions in machine learning in recent years. In this work we study the brain-like Bayesian Confidence Propagating Neural Network (BCPNN) model, recently extended to extract sparse distributed high-dimensional representations. The saliency and separability of the hidden representations when trained on MNIST dataset is studied using an external classifier, and compared with other unsupervised learning methods that include restricted Boltzmann machines and autoencoders.




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Parametrized Universality Problems for One-Counter Nets. (arXiv:2005.03435v1 [cs.FL])

We study the language universality problem for One-Counter Nets, also known as 1-dimensional Vector Addition Systems with States (1-VASS), parameterized either with an initial counter value, or with an upper bound on the allowed counter value during runs. The language accepted by an OCN (defined by reaching a final control state) is monotone in both parameters. This yields two natural questions: 1) Does there exist an initial counter value that makes the language universal? 2) Does there exist a sufficiently high ceiling so that the bounded language is universal? Despite the fact that unparameterized universality is Ackermann-complete and that these problems seem to reduce to checking basic structural properties of the underlying automaton, we show that in fact both problems are undecidable. We also look into the complexities of the problems for several decidable subclasses, namely for unambiguous, and deterministic systems, and for those over a single-letter alphabet.




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Specification and Automated Analysis of Inter-Parameter Dependencies in Web APIs. (arXiv:2005.03320v1 [cs.SE])

Web services often impose inter-parameter dependencies that restrict the way in which two or more input parameters can be combined to form valid calls to the service. Unfortunately, current specification languages for web services like the OpenAPI Specification (OAS) provide no support for the formal description of such dependencies, which makes it hardly possible to automatically discover and interact with services without human intervention. In this article, we present an approach for the specification and automated analysis of inter-parameter dependencies in web APIs. We first present a domain-specific language, called Inter-parameter Dependency Language (IDL), for the specification of dependencies among input parameters in web services. Then, we propose a mapping to translate an IDL document into a constraint satisfaction problem (CSP), enabling the automated analysis of IDL specifications using standard CSP-based reasoning operations. Specifically, we present a catalogue of nine analysis operations on IDL documents allowing to compute, for example, whether a given request satisfies all the dependencies of the service. Finally, we present a tool suite including an editor, a parser, an OAS extension, a constraint programming-aided library, and a test suite supporting IDL specifications and their analyses. Together, these contributions pave the way for a new range of specification-driven applications in areas such as code generation and testing.




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Cotatron: Transcription-Guided Speech Encoder for Any-to-Many Voice Conversion without Parallel Data. (arXiv:2005.03295v1 [eess.AS])

We propose Cotatron, a transcription-guided speech encoder for speaker-independent linguistic representation. Cotatron is based on the multispeaker TTS architecture and can be trained with conventional TTS datasets. We train a voice conversion system to reconstruct speech with Cotatron features, which is similar to the previous methods based on Phonetic Posteriorgram (PPG). By training and evaluating our system with 108 speakers from the VCTK dataset, we outperform the previous method in terms of both naturalness and speaker similarity. Our system can also convert speech from speakers that are unseen during training, and utilize ASR to automate the transcription with minimal reduction of the performance. Audio samples are available at https://mindslab-ai.github.io/cotatron, and the code with a pre-trained model will be made available soon.




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A Parameterized Perspective on Attacking and Defending Elections. (arXiv:2005.03176v1 [cs.GT])

We consider the problem of protecting and manipulating elections by recounting and changing ballots, respectively. Our setting involves a plurality-based election held across multiple districts, and the problem formulations are based on the model proposed recently by~[Elkind et al, IJCAI 2019]. It turns out that both of the manipulation and protection problems are NP-complete even in fairly simple settings. We study these problems from a parameterized perspective with the goal of establishing a more detailed complexity landscape. The parameters we consider include the number of voters, and the budgets of the attacker and the defender. While we observe fixed-parameter tractability when parameterizing by number of voters, our main contribution is a demonstration of parameterized hardness when working with the budgets of the attacker and the defender.




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A Separation Theorem for Joint Sensor and Actuator Scheduling with Guaranteed Performance Bounds. (arXiv:2005.03143v1 [eess.SY])

We study the problem of jointly designing a sparse sensor and actuator schedule for linear dynamical systems while guaranteeing a control/estimation performance that approximates the fully sensed/actuated setting. We further prove a separation principle, showing that the problem can be decomposed into finding sensor and actuator schedules separately. However, it is shown that this problem cannot be efficiently solved or approximated in polynomial, or even quasi-polynomial time for time-invariant sensor/actuator schedules; instead, we develop deterministic polynomial-time algorithms for a time-varying sensor/actuator schedule with guaranteed approximation bounds. Our main result is to provide a polynomial-time joint actuator and sensor schedule that on average selects only a constant number of sensors and actuators at each time step, irrespective of the dimension of the system. The key idea is to sparsify the controllability and observability Gramians while providing approximation guarantees for Hankel singular values. This idea is inspired by recent results in theoretical computer science literature on sparsification.




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A Multifactorial Optimization Paradigm for Linkage Tree Genetic Algorithm. (arXiv:2005.03090v1 [cs.NE])

Linkage Tree Genetic Algorithm (LTGA) is an effective Evolutionary Algorithm (EA) to solve complex problems using the linkage information between problem variables. LTGA performs well in various kinds of single-task optimization and yields promising results in comparison with the canonical genetic algorithm. However, LTGA is an unsuitable method for dealing with multi-task optimization problems. On the other hand, Multifactorial Optimization (MFO) can simultaneously solve independent optimization problems, which are encoded in a unified representation to take advantage of the process of knowledge transfer. In this paper, we introduce Multifactorial Linkage Tree Genetic Algorithm (MF-LTGA) by combining the main features of both LTGA and MFO. MF-LTGA is able to tackle multiple optimization tasks at the same time, each task learns the dependency between problem variables from the shared representation. This knowledge serves to determine the high-quality partial solutions for supporting other tasks in exploring the search space. Moreover, MF-LTGA speeds up convergence because of knowledge transfer of relevant problems. We demonstrate the effectiveness of the proposed algorithm on two benchmark problems: Clustered Shortest-Path Tree Problem and Deceptive Trap Function. In comparison to LTGA and existing methods, MF-LTGA outperforms in quality of the solution or in computation time.




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Process for the preparation of O-desmethyl venlafaxine and intermediate for use therein

The present invention relates to a compound of formula A, wherein R is alkyl. Compound A may be used as an intermediate in the preparation of O-desmethyl venlafaxine or a salt thereof, and the present invention provides such a preparation, as well as a process for preparing the compound of formula A.




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Method for preparation of aryl poly(oxalkyl) quaternary ammonium compound

A method for preparation of an aryl poly(oxalkyl) quaternary ammonium compound is provided, said method comprising steps of: 1) reacting a phenol with a dihalopolyalkylene ether under the action of a phase transfer catalyst, to obtain an arylpoly(oxalkyl) halide; 2) reacting said arylpoly(oxalkyl) halide with an amination reagent under the action of a phase transfer catalyst, to obtain an arylpoly(oxalkyl) amine; 3) reacting said arylpoly(oxalkyl) amine with an alkylation reagent, to obtain an aryl poly(oxalkyl) quaternary ammonium compound; wherein R1 is H or a C1 to C16 alkyl group, located in the ortho, meta or para position; n is an integer of 2 to 6; R2 is H or a C1 to C16 alkyl group; R3 is H or a C1 to C16 alkyl group; R4 is a C1 to C16 alkyl group; X1 is Br or Cl; X is Cl, Br, or I. The preparation method according to the present invention requires low temperature and low pressure, the reaction time is short, and an overall yield can reach 75%. The operation is simple, the cost is low, and the product can be separated easily and have a purity of pharmaceutical grade, thereby facilitating the large-scale production.




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Process for the preparation of crystalline forms of agomelatine and novel polymorph thereof

The invention concerns a new process for the preparation of crystalline form of agomelatine from a solution of agomelatine in a solvent, characterized in that the agomelatine is crystallized by instantaneous precipitation from said solution, at a temperature equal to or below −10° C.




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Apparatus and method for selecting motion signifying artificial feeling

An apparatus for selecting a motion signifying artificial feeling is provided. The apparatus includes: an feeling expression setting unit configured to set probabilities of each feeling expression behavior performed for each expression element of a robot for each predetermined feeling; a behavior combination generation unit configured to generate at least one behavior combination combined by randomly extracting the feeling expression behaviors in each expression element one by one; and a behavior combination selection unit configured to calculate an average for the probabilities of the feeling expression behaviors included in each behavior combination for each feeling of a robot and select behavior combinations in which the average of the probabilities of the feeling expression behaviors most approximates the predetermined feeling value of a robot from each behavior combination.




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Apparatus and method for recognizing representative user behavior based on recognition of unit behaviors

An apparatus for recognizing a representative user behavior includes a unit-data extracting unit configured to extract at least one unit data from sensor data, a feature-information extracting unit configured to extract feature information from each of the at least one unit data, a unit-behavior recognizing unit configured to recognize a respective unit behavior for each of the at least one unit data based on the feature information, and a representative-behavior recognizing unit configured to recognize at least one representative behavior based on the respective unit behavior recognized for each of the at least one unit data.




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Method and apparatus for contextual content suggestion

An approach is provided for contextual content suggestion. A recommendation platform processes and/or facilitates a processing of contextual information associated with at least one device to determine one or more locations, one or more contextual parameter values, or a combination thereof. The recommendation platform also determines popularity data associated with one or more content items with respect to the one or more locations, the one or more contextual parameter values, or a combination. The popularity data is determined from one or more other devices sharing at least substantially the one or more locations, the one or more contextual parameter values, or a combination thereof. The recommendation platform then causes, at least in part, a recommendation of the one or more content items to the at least one device based, at least in part, on the popularity information.




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Latent variable model estimation apparatus, and method

To provide a latent variable model estimation apparatus capable of implementing the model selection at high speed even if the number of model candidates increases exponentially as the latent state number and the kind of the observation probability increase. A variational probability calculating unit 71 calculates a variational probability by maximizing a reference value that is defined as a lower bound of an approximation amount, in which Laplace approximation of a marginalized log likelihood function is performed with respect to an estimator for a complete variable. A model estimation unit 72 estimates an optimum latent variable model by estimating the kind and a parameter of the observation probability with respect to each latent state. A convergence determination unit 73 determines whether a reference value, which is used by the variational probability calculating unit 71 to calculate the variational probability, converges.




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Information providing apparatus for vehicle, and method therefor

An information providing apparatus for vehicle has a remaining capacity detecting section 110 that detects a remaining capacity of a battery; a power consumption amount detecting section 130 that detects a power consumption amount of the battery; a power consumption amount history generating section 130 that generates a power consumption amount history on the basis of the power consumption amount detected by the power consumption amount detecting section 130; a charge necessity judgment information generating section 130 that generates, on the basis of the power consumption amount history generated by the power consumption amount history generating section 130, charge necessity judgment information which is information for user's judgment about whether or not charging of the battery is necessary; and a providing section 150 that provides information of the remaining capacity of the battery and the charge necessity judgment information with these information correlated with each other to the user. The information providing apparatus can properly provide the information for user's judgment about whether or not charging of the battery to the user.




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Method and apparatus for declarative data warehouse definition for object-relational mapped objects

A data warehouse is constructed using the relational mapping of a transactional database without reconstructing the data relationships of the transactional database. First, an application programmer analyzes an object model in order to describe facts and dimensions using the objects, attributes, and paths of the object model. Each of the dimensions has an identifier that correlates an item in the transactional database to a dimension record in the data warehouse. The fact and dimension descriptions are saved to a description file. Second, a Data Warehouse Engine (DWE) then access the description file and uses the object model, fact and dimension descriptions, and object-relational mapping to map transactional data to the data warehouse.




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Process for separation of renewable materials from microorganisms

Methods of separating renewable materials, such as lipids, from microorganisms, such as oleaginous yeasts, may include conditioning cell walls of the microorganisms to form, open or enlarge pores, and removing at least a portion of the renewable material through the pores. These methods may result in delipidated microorganisms with cell walls that are substantially intact and with mesopores. These delipidated microorganisms may be used to produce biofuels.




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Using cavitation to increase oil separation

Methods and systems are provided that apply cavitation to a grain-based liquid medium processing stream of an oil separation process in order to achieve increased yields. Ultrasonic sources can be used in generating the cavitation. Typically, the oil processing system is a downstream process of an alcohol (such as ethanol) production facility utilizing a dry grind, a modified dry grind or a wet mill alcohol production process.




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Ceramide dimers and use thereof as pharmaceutical preparation or cosmetic preparation

The invention relates to ceramide dimers which are constructed from two ceramide molecules which are crosslinked to each other via their lipophilic end. The ceramide molecules thereby have at least one hydrophilic group at their hydrophilic end for increasing the hydration shell of the dimer. The ceramide dimers according to the invention can be used as pharmaceutical preparation or as cosmetic preparation.




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Composition for cosmetics, cosmetic, method for producing oil-in-water emulsion cosmetic, and two separate layer-type cosmetic

The present invention relates to a composition for cosmetics including a polyglycerol fatty acid ester, which is an ester of polyglycerol having an average degree of polymerization of 4 to 100 with a fatty acid having 2 to 18 carbon atoms, has a hydroxyl value equal to or less than 15 mgKOH/g, and has a specific gravity at 20° C. of 0.96 to 1.15; a cosmetic which includes the composition for cosmetics; a method for producing an oil-in-water emulsion cosmetic which includes mixing the composition for cosmetics; and a two-separate-layer-type cosmetic, which comprises the composition for cosmetics. The present invention relates to the composition for cosmetics which can be appropriately used in producing a cosmetic giving a highly excellent feel in using and having a very good texture, a cosmetic showing a very high stability over time as an emulsion, and a two-separate-layer-type cosmetic.




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Composition for cosmetics, cosmetic, method for producing oil-in-water emulsion cosmetic, and two separate layer-type cosmetic

The present invention relates to a composition for cosmetics including a polyglycerol fatty acid ester, which is an ester of polyglycerol having an average degree of polymerization of 4 to 100 with a fatty acid having 2 to 18 carbon atoms, has a hydroxyl value equal to or less than 15 mgKOH/g, and has a specific gravity at 20° C. of 0.96 to 1.15; a cosmetic which includes the composition for cosmetics; a method for producing an oil-in-water emulsion cosmetic which includes mixing the composition for cosmetics; and a two-separate-layer-type cosmetic, which comprises the composition for cosmetics. The present invention relates to the composition for cosmetics which can be appropriately used in producing a cosmetic giving a highly excellent feel in using and having a very good texture, a cosmetic showing a very high stability over time as an emulsion, and a two-separate-layer-type cosmetic.




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Process for the preparation of fatty acid alkyl esters (biodiesel) from triglyceride oils using eco-friendly solid base catalysts

This invention relates to an improved process for the preparation of green fatty acid methyl esters (FAME; commonly called as biodiesel) from different triglyceride oils using mixed metal oxides derived from layered double hydroxides (referred here as LDHs) as reusable solid heterogeneous base catalysts. This process uses very low alcohohoil molar ratio and catalyst and/or products are easily separable after the reaction through simple physical processes. The properties of thus obtained biodiesel meet the standard biodiesel values and can directly be used as transport fuel.




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Process for the preparation of chiral triazolones

A process for the preparation of a chiral compound, in particular posaconazole, wherein the process comprises mixing and reacting the compounds of formula (I) Y3—NH2; of formula (IIa) 0=C═N—Y0 and/or of formula (IIb) and of formula (III) in a solvent in any order to obtain a reaction mixture containing a chiral compound of formula (IV) and/or formula (V).




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Novel 6-acyl-(6H)-dibenz[c,e][1,2]oxaphosphorin 6-oxides, their preparation and their use as photoinitiators

The invention relates 6-acyl-(6H)-dibenz[c,e][1,2]oxaphosphorin-6-oxides of the formula ##STR1## wherein each of R1, R2 and R3 may be present one or more times and R1, R2 and R3 represent halogen having an atomic number of from 9 to 35, alkyl or alkoxy each having from 1 to 6 carbon atoms and wherein Ar represents an aromatic hydrocarbon group having from 6 to 10 carbon atoms.The invention further relates to a process for the preparation of the afore-mentioned compounds and polymerizable compositions containing them as an essential ingredient as a photo-initiator. Finally the invention relates to 6-alkoxy-(6H)-dibenz[c,e][1,2]oxaphosphorin of the formula II ##STR2## wherein each of R1 and R2 may be present once or more times and R1 and R2 represent halogen having an atomic number of from 9 to 35, alkyl or alkoxy each having from 1 to 6 carbon atoms, at least one R1 being, however, halogen and wherein R4 represents alkyl having from 1 to 6 carbon atoms.




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Process for the preparation of oligonucleotides

The invention relates to a process for the preparation of oligonucleotides by the following steps: reaction of a nucleoside with a phosphine derivative, reaction of the nucleotide derivative thus obtained with a nucleoside bonded to a polymeric carrier, oxidation of the carrier-bound nucleoside-nucleotide thus obtained with formation of phosphotriester groups, blocking of free primary 5'--OH groups, elimination of a protective group from the terminal 5'--OH group, where appropriate single or multiple repetition of the abovementioned steps to introduce further nucleoside phosphate or oligonucleoside phosphate units, and cleavage of the nucleoside-carrier bond and, where appropriate, elimination of all protective groups present in the oligonucleoside phosphates. The phosphine derivative used is a compound of the general formula III ##STR1## in which X and L can react with OH groups of the sugar units in the oligonucleotides, and R3 is a protective group which can be liberated by β-elimination.




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Derivatives of purine, process for their preparation and a pharmaceutical preparation

Antivirally active compounds of formula (I), wherein R1 is hydrogen, hydroxy, mercapto or amino; R2 is hydrogen, hydroxy, fluoro, chloro or amino; R3 and R4 are independently selected from (II), (III), amino, hydroxy or an ether or ester residue thereof, or R3 together with R4 is (IV), wherein M is hydrogen or a pharmaceutically acceptable counterion; and n is 1 or 2; with the proviso that, when R2 is amino and R3 and R4 are hydroxy, R1 is not hydroxy and in addition, when n=1, R1 is not hydrogen, and pharmaceutically acceptable salts thereof; processes for preparation of said compounds, a pharmaceutical composition comprising said compounds, methods for treatments of virus infections as well as use of compounds of formula (I) without the proviso for the manufacture of a medicament for treatment of AIDS. ##STR1##




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Bridged bis-fluorenyl metallocenes, process for the preparation thereof and use thereof in catalysts for the polymerization of olefins

Metallocene compounds having two fluorenyl ligands bridged with a single silicon or germanium atom, said atom having two substituent groups containing a total of at least four carbon atoms, are useful as catalyst components for the polymerization of olefins. Particularly, it is possible to prepare high molecular weight atactic polypropylene with improved yields with respect to the known catalysts.




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Diene complexes of group 4 metals and process of preparation

Disclosed is a process for preparing bridged Group 4 metal complexes containing a neutral diene ligand starting from the corresponding novel, metal diene containing complexes by reaction thereof with the divalent derivative of a bridged bidentate ligand compound. The novel, intermediate metal diene complexes, their formation from tetravalent metal salts and an integrated process combining both process steps are claimed.




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Preparation of addition polymerization catalysts

Metal complexes useful as components of addition polymerization catalysts are prepared by oxidizing Group 4 or Lanthanide metal containing complexes using an organic halide oxidizing agent in a unique one electron oxidation.




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Method for removing parasites and in particular ectoparasites of vertebrates, in particular of mammals, and compositions for the implementation of this method

Methods for removing parasites and in particular ectoparasites of vertebrates, in particular of mammals, and compositions for the implementation of this method.Methods for removing parasites of vertebrates, and in particular arthropods, mainly insects and Arachnida, wherein an effectively parasiticidal amount of a compound of formula (I) ##STR1## in particular of fipronil, is administered to the animal via an administration route which makes possible systemic distribution and good absorption.




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Metallocene compounds, processes for the preparation thereof, catalyst components for olefin polymerization, and processes for the production of olefin polymers

A metallocene compound is provided wherein to a transition metal compound is bonded a multidentate compound wherein a substituted cycloalkadienyl ring CA1 having therein a heteroaromatic group Ra containing an oxygen, sulfur or nitrogen atom on a cycloalkadienyl ring, preferably the five-membered ring thereof, and an unsubstituted or substituted cycloalkadienyl group CA2 or --(R1)N--, --O--, --S-- or --(R1)P--, preferably CA2, more preferably a substituted cycloalkadienyl group identical with CA1 are bonded through a divalent linking group. The metallocene compound is suitable as a principal ingredient of a catalyst for the polymerization of olefins, particularly achieving a very high effect in making the molecular weight of a polypropylene higher.




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Process for the preparation of polyether phosphates

The invention provides an improved process for the synthesis of compounds carrying at least one phosphate group, especially polyalkylene glycol phosphate compounds, said process comprising the steps of: (a) reacting a compound containing at least one primary alcohol moiety with a diaryl- or diaralkyl-halophosphate whereby to form the corresponding diaryl- or diaralkyl-phosphate ester; (b) reductively cleaving the resulting product; and (c) if desired, repeating steps (a) and (b) with the product of step (b) whereby to produce a compound carrying two or more phosphate groups. Advantages of the process in accordance with the invention are that this avoids the production of by-products and results in products which are low in impurities. Also provided are novel diaryl- and diaralkyl-phosphate ester compounds, in particular polyethylene glycol diphenylphosphate ester and derivatives thereof.




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Preparation of triethyl phosphate

The invention relates to a process for preparing triethyl phosphate by reacting phosphorus oxychloride with a greater than stoichiometric quantity of ethanol under reduced pressure at temperatures of from 0 to 50° C. in a reaction vessel, wherein a) the volatile components resulting from the reaction are predominantly condensed by means of a reflux condenser and the remaining volatile components are passed into a scrubber filled with water,b) after the end of the reaction, the reaction mixture is separated distillatively in an outgassing column into a top product and a bottom product which predominantly comprises triethyl phosphate,c) the top product of the outgassing column is combined with the contents of the scrubber andd) the contents of the scrubber are separated distillatively in an azeotropic distillation to obtain water and ethanol as top product and the ethanol, preferably after dewatering, is preferably returned to the reaction.




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Preparation of silicon-bridged metallocene compounds

A process for obtaining silicon-bridged metallocene compounds comprising the following steps: a) reacting, at a temperature of between −10° C. and 70° C., the starting ligand with about 2 molar equivalents of an alkylating agent;b) after the reaction has been completed, adding at least 2 molar equivalents of an alkylating agent that can be also different from the first one; andc) reacting, at a temperature of between −10° C. and 70° C., the product obtained from step b) with at least 1 molar equivalent of a compound of formula ML's, wherein M is a transition metal; s is an integer corresponding to the oxidation state of the metal; and L' is an halogen atom selected from chlorine, bromine and iodine.




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Glass for magnetic recording media substrates, magnetic recording media substrates, magnetic recording media and method for preparation thereof

A glass for a magnetic recording medium substrate permitting the realization of a magnetic recording medium substrate affording good chemical durability and having an extremely flat surface, a magnetic recording medium substrate comprised of this glass, a magnetic recording medium equipped with this substrate, and methods of manufacturing the same. The glass is an oxide glass not including As or F.




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Zeolite separation membrane, method for producing the same, and bonding agent

A separation membrane according to the present invention is characterized by having a porous tube containing an alumina as a main component and an attachment member disposed in a connection position of the porous tube, wherein the porous tube and the attachment member are bonded by a ceramic oxide-based bonding agent containing 17 to 48 wt % of SiO2, 2 to 8 wt % of Al2O3, 24 to 60 wt % of BaO, and 0.5 to 5 wt % of ZnO as essential components and containing at least one of La2O3, CaO, and SrO, and a thin zeolite layer is formed on a surface of the porous tube. The attachment member is bonded to the porous tube before the formation of the zeolite layer. Therefore, the bonding agent can have a melting temperature higher than 600° C., which is the upper heatproof temperature limit of the zeolite. Thus, the ceramic oxide material for the bonding agent can be selected from a wider range of compositions such as glass compositions (without limitations on the glass softening temperature).




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Dielectric composition and preparation method thereof

There are provided a dielectric composition and a preparation method thereof, the dielectric composition including: a first perovskite powder for a core represented by ABO3: and a second perovskite powder for a shell represented by ABO3, having an average particle diameter corresponding to ⅓ to 1/10 of an average particle diameter of the first perovskite powder, and included in an amount of 1 to 70 parts by weight with respect to 100 parts by weight of the first perovskite powder, wherein particles of the second perovskite powder have pores having a volume fraction of 3 to 50 vol % therein. According to the present invention, there are provided a dielectric composition having excellent dielectric characteristics and electrical characteristics, and a preparation method thereof.




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Separation of components from a multi-component hydrocarbon stream which includes ethylene

A process to separate a multi-component hydrocarbon stream which includes ethylene and other components with at least some of the components being present in a number of phases, is provided. The process includes in a first flash stage, flashing the multi-component hydrocarbon stream, from an elevated pressure and temperature to a pressure in the range of 10-18 bar(a), producing a first ethylene-containing vapor stream at a pressure in the range of 10-18 bar(a) and a multi-phase stream which includes some ethylene. In a second flash stage, the multi-phase stream is flashed to a pressure of less than 6 bar(a), producing a second vapor stream at a pressure of less than 6 bar(a) and a bottoms stream. The first ethylene-containing vapor stream is removed from the first flash stage, the second vapor stream is removed from the second flash stage and the bottoms stream is removed from the second flash stage.




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Method and apparatus for preparing fuel components from crude tall oil

A method for preparing fuel components from crude tall oil. Feedstock containing tall oil including unsaturated fatty acids is introduced to a catalytic hydrodeoxygenation to convert unsaturated fatty acids, rosin acids and sterols to fuel components. Crude tall oil is purified in a purification by washing the crude tall oil with washing liquid and separating the purified crude tall oil from the washing liquid. The purified crude tall oil is introduced directly to the catalytic hydrodeoxygenation as a purified crude tall oil feedstock. An additional feedstock may be supplied to the catalytic hydrodeoxygenation.




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Method for quenching paraffin dehydrogenation reaction in counter-current reactor

A process is presented for quenching a process stream in a paraffin dehydrogenation process. The process comprises cooling a propane dehydrogenation stream during the hot residence time after the process stream leaves the catalytic bed reactor section. The process includes cooling and compressing the product stream, taking a portion of the product stream and passing the portion of the product stream to the mix with the process stream as it leaves the catalytic bed reactor section.




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Methods and apparatuses for isomerization of paraffins

Embodiments of methods and apparatuses for isomerization of paraffins are provided. In one example, a method comprises the steps of separating an isomerization effluent into a product stream that comprises branched paraffins and a stabilizer vapor stream that comprises HCl, H2, and C6-hydrocarbons. C6-hydrocarbons are removed from the stabilizer overhead vapor stream to form a HCl and H2-rich stream. An isomerization catalyst is activated using at least a portion of the HCl and H2-rich stream to form a chloride-promoted isomerization catalyst. A paraffin feed stream is contacted with the chloride-promoted isomerization catalyst in the presence of hydrogen for isomerization of the paraffins.