bluuebunny/crossref_metadata_2025_split huggingface dataset:
Carbonylation
Authors: Bertleff Werner , Roeper Michael , Sava Xavier 
Published: August 2007

AbstractThe article contains sections titled:1.Introduction2.Catalysts2.1.Nickel Catalysts2.2.Cobalt Catalysts2.3.Palladium Catalysts2.4.Rhodium and Iridium Catalysts3.Carbonylation of Alkynes3.1.Acrylic Acid from Acetylene3.2.Other Carbonylation Reactions of Alkynes4.Carbonylation of Alkenes4.1.Monoalkenes4.2.Substituted Alkenes4.3.Polyenes5.Carbonylation of Alcohols and Ethers5.1.BASF Acetic Acid Process5.2.Monsanto Acetic Acid Process5.3.Carbonylation of Other Alcohols and Ethers6.Carbonylation of Organic Halides6.1.Aryl Halides6.2.Alkyl Halides6.3.Allyl Halides and Vinyl Halides7.Other Carbonylation Reactions7.1.Amines7.2.Aromatic Nitro Compounds7.3.Esters7.4.Lactones and Aldehydes7.5.Amidocarbonylation of Aldehydes
Lignin
Authors: Saake Bodo , Lehnen Ralph 
Published: August 2007

AbstractThe article contains sections titled:1.Occurrence and Functions2.Structure and Biosynthesis3.Physical Properties4.Chemical Properties4.1.Kraft Pulping4.2.Sulfite Pulping4.3.Other Pulping Processes4.4.Pulp Bleaching4.5.Yellowing Reactions5.Commercial Lignins6.Analysis6.1.Detection and Quantification6.2.Isolation6.3.Spectroscopic Methods6.4.Degradation Methods6.5.Molar Mass Determination7.Uses8.Toxicology
Hydrocyclones
Authors: Ortega‐Rivas Enrique 
Published: August 2007

Abstract

1.

Introduction

1.1

General Remarks

1.2

Principle of Operation

2.

Categories and Applications

2.1

Thickening

2.2

Clarification

2.3

Classification

2.4

Other Applications

3.

Theoretical Background

3.1

Simultaneous Flow of Fluids and Solids

3.1.1

Dynamics of Particles Submerged in Fluids

3.1.3

Rheology of Suspensions

3.1.4

Flow of Suspension

3.2

Flow Patterns in Hydrocylones

3.3

Mechanics of Particle Separation

3.3.1

Equilibrium‐Orbit Theory

3.3.2

Residence‐Time Theory

3.3.3

Crowding Theory

3.3.4

Turbulent two‐phase Flow Theory

3.4

Characteristics of Performance of Hydrocylones

3.4.1

Separation Efficiency. Cut Size

3.4.2

Capacity. Pressure Drop

4.

Effect of Variables on Hydrocyclone Performance

4.1

Operating Variables

4.2

Design Variables

5.

Selection and Design of Hydrocyclone Systems

5.1

Analytical Solutions

5.2

Graphical Solutions

5.3

Manufacturers' Choice

5.4

Dimensionless Scale‐up

5.4.1

Introduction

5.4.2

Definitions and Derivations of Dimensionless Groups

5.4.3

Scale‐Up at Low Concentrations

5.4.4

Scale‐Up at High Concentrations

5.4.5

Considerations for Non‐Newtonian Behavior

5.4.6

Empirical Models

5.4.7

Practical Applications

Hydrocyclone technology has been suggested as a practical alternative for solid–liquid separations in many applications in diverse industries. The hydrocyclone is easy to install, test and operate, and requires very limited space. It represents an unsophisticated piece of equipment which runs in a continuous manner and it can be operated at lower costs than most of the solid–liquid separation devices. Hydrocyclones have been used in liquid–solid, liquid–liquid, or liquid–gas separations, and can perform varied duties in industries as diverse as mineral processing, chemical engineering, food processing, biotechnology, oil and gas. They have been used not only as separators, but also as clarifiers, classifiers, and in some other applications. This article reviews theoretical aspects of hydrocyclone operation and gives some insight into different applications of hydrocyclone technology.
Radial‐Flow Packed‐Bed Reactors
Authors: Li Jeff C. H. 
Published: August 2007

Abstract
The article contains sections titled:

1.

Introduction

2.

Applications of Radial‐Flow Reactors

3.

Design of Commercial Radial‐Flow Reactors

4.

Flow Distribution

5.

Catalyst Basket Design

6.

Catalyst Settling and Flow Bypassing

7.

Acknowledgments

The radial‐flow packed‐bed reactor is a design with very small pressure drop and most suitable for large‐capacity plants. It has replaced the axial‐flow reactor for several important chemical processes such as ammonia synthesis, ethylbenzene dehydrogenation, and catalytic reforming. The design of a radial‐flow reactor is more complicated than that of an axial‐flow reactor; it must deal with several unique concerns: flow distribution along the length of the reactor, thermal reaction in the void space, catalyst settling, and expansion and contraction of the catalyst basket. The successful operation of a commercial radial‐flow reactor lies mainly in the details of the mechanical design.
Dynamic effects for two‐phase flow in porous media: Fluid property effects
Authors: Das Diganta Bhusan , Gauldie Robert , Mirzaei Mahsanam 
Published: August 2007

AbstractTraditional descriptions of multiphase flow in porous media rely on an extension of Darcy's law along with relationships between capillary pressure (Pc), saturation (S), and relative permeability (Kr). New theories have been proposed which suggest that Pc relationships should include a dynamic coefficient (τ) (Hassanizadeh and Gray, Water Resour Res. 1993;29:3389–3405) to indicate how “quickly” or “slowly” flow equilibrium is reached. While validity of these theories must be examined, it is also necessary to determine the significance of τ and its range of values. In this article, we analyze the significance of τ depending on fluid properties. We address the ways in which they cause nonuniqueness of dynamic two‐phase flow in porous media and, hence, dynamic effect. Simulations are conducted for quasi‐static and dynamic flow of perchloroethylene (PCE) in water saturated domains. The data are then fitted to the dynamic Pc relationships to obtain values of τ. The effects of flow directions and, viscosity and density ratios are discussed. To consider the lumped effects of various fluid properties, τ–S relationships are examined for silicone oils. The results are interpreted by examining the correlation between τ and a mobility coefficient, m. We discuss a scaling relationship that shows the dependence of τ on fluid and material properties. © 2007 American Institute of Chemical Engineers AIChE J, 2007
Synthesis and characterization of diorganotin(IV) complexes of Schiff bases with ONO‐type donors and crystal structure of [N‐(2‐hydroxy‐4‐nitrophenyl)‐3‐ethoxysalicylideneiminato]diphenyltin(IV)
Authors: Çelebier Mustafa , Şahin Ertan , Ancın Nilgün , Öztaş Nurşen Altuntaş , Öztaş Selma Gül 
Published: August 2007

AbstractA series of neutral complexes, namely, [N‐(2‐hydroxy‐4‐nitrophenyl)‐3‐hydroxysalicylideneiminato]‐ diphenyltin(IV) (Ia), [N‐(2‐hydroxy‐4‐nitrophenyl)‐3‐methoxysalicylideneiminato]diphenyltin(IV) (IIa) and [N‐(2‐hydroxy‐4‐nitrophenyl)‐3‐ethoxysalicylideneiminato]diphenyltin(IV) (IIIa) were prepared by the reaction of diphenyltin dichloride on the corresponding Schiff bases. The Schiff bases were the reaction products of 2‐hydroxy‐4‐nitroaniline and appropriate salicylaldehydes. All the compounds were characterized by elemental analysis, 1H‐NMR, 13C‐NMR, IR and mass spectroscopy. Compound IIIa was also characterized by single crystal X‐ray diffraction and shows a C2NO2 coordination geometry nearly half‐way between a trigonal bipyramidal and square pyramidal arrangement. In the solid state, π− π interactions exist between the aniline fragments of neighbouring molecules. Copyright © 2007 John Wiley & Sons, Ltd.
Depolymerization during nitroxide‐mediated oxidation of native cellulose
Authors: Milichovsky Miloslav , Sopuch Tomáš , Richter Jaroslav 
Published: August 2007

AbstractThe kinetics and mechanism of depolymerization during nitroxide‐mediated oxidation of native cellulose has been studied under various conditions. The physical heterogeneity of the native cellulose and its complicated hypermolecular and supramolecular structure exerts a remarkable influence on the kinetics of oxidation and depolymerization. A strong influence of external tension applied on cellulose gauze reactivity during its oxidation has been proven, which is caused by its complicated hypermolecular structure. Celluloronic acids were obtained by the application of external tension during selective oxidation of native cellulose textiles. The cellouronic acids contained the higher amount of carboxyl groups but they also had a lower intrinsic viscosity, i.e., the average degree of polymerization (DP). The mathematical model—so‐called DP‐peeling off model—has been derived to describe the kinetics of cellulose depolymerization based on experimental data obtained. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Alignment of electrospun polystyrene with an electric field
Authors: Chanunpanich N. , Byun Hongsik 
Published: August 2007

AbstractPolystyrene (PS) with a concentration of 20% by weight in THF/DMF was electrospun on a flat sheet collector. At a concentration of THF above 75%, blocking at the needle tip caused bead formation. However, a nice fiber mat was obtained with the 75/25 THF/DMF. Moreover, at a traveling distance of 10 and 15 cm and voltages from 10 to 16 kV, the PS fibers exhibited alignment. This alignment was reproducible when voltage stabilizer was connected to the voltage supply. This suggested that the uniformly positive charges arising from external voltage interacted with the aromatic rings on the PS chain, yielding a uniform dipole moment. As a result, during jet traveling, the solvent evaporated and the molecules were oriented and frozen at the ground collector. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Polyetherols obtained from 6‐aminouracil and ethylene carbonate
Authors: Chmiel‐Szukiewicz Elżbieta 
Published: August 2007

AbstractThe reactions of 6‐aminouracil with ethylene carbonate were investigated. Potassium carbonate or 1,4‐diazabicyclo[2.2.2]octane was used as a catalyst. An excess of ethylene carbonate was applied in the syntheses. In this way, polyetherols with 1,3‐pyrimidine rings in their structure were prepared. The structure of the products was analyzed with infrared, proton nuclear magnetic resonance, and matrix‐assisted laser desorption/ionization time‐of‐flight techniques. Some physical properties and the thermal stability of the prepared polyetherols were investigated. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Preparation of multiwalled carbon nanotube/nylon‐6 nanocomposites by in situ polymerization
Authors: Saeed Khalid , Park Soo‐Young 
Published: August 2007

AbstractMultiwalled carbon nanotube/nylon‐6 nanocomposites (MWNT/nylon) were prepared by in situ polymerization, whereby pristine MWNTs (P‐MWNTs) and purified MWNTs (A‐MWNTs) were used as reinforcing materials. The A‐MWNTs were purified by nitric acid treatment, which introduced the carboxyl groups (COOH) to the MWNTs. The SEM micrographs from the fractured surfaces of the nanocomposites showed that the A‐MWNTs were well dispersed in A‐MWNT/nylon as compared to the P‐MWNTs in P‐MWNT/nylon. The percolation thresholds of P‐MWNT/nylon and A‐MWNT/nylon, which were studied by rheological properties, were found at ∼ 1 wt % of the MWNTs. The conductivity of P‐MWNT/nylon and A‐MWNT/nylon were 3.15 × 10−5 and 7.46 × 10−5 S/cm by the loading of 5 and 7 wt % of MWNTs, respectively. Differential scanning calorimetry (DSC) showed that the crystallization temperatures of P‐MWNT/nylon and A‐MWNT/nylon (195°C) increased more than that of pure nylon (189°C) due to the nucleation effect of MWNTs. Wide‐angle X‐ray analysis indicated that the incorporation of MWNTs into the nylon matrix resulted only in α‐crystalline structure, which were quite different from those reported for the clay/nylon nanocomposite (show both α‐ and γ‐crystals). It might be due to the different geometry between the MWNTs and the nanoclay platelets, which have one and two‐dimensional geometry, respectively. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Moldability and properties of phenolic/artificial zeolite composites
Authors: Matsumoto Akihiro , Ohtsuka Keiko , Kimura Hajime , Adachi Shin‐ich , Takenaka Minoru 
Published: August 2007

AbstractThe purpose of this study is to improve the several properties of composites consisting of a phenolic and fly ash or artificial Zeolite such as sodium type Zeolite (NaZe) or calcium type Zeolite(CaZe). And it also includes the improvement in the flowability of molding compounds. The molding compounds were prepared from a phenol novolac, a curing agent, and several fillers. The flowability of the compounds containing fly ash and artificial Zeolite as a filler, mentioned above, was superior to that of the compounds containing glass fiber (GF), calcium carbonate (CaCO3), or talc as a filler. The phenolic composites were prepared from the above molding compounds by transfer molding. The phenolic composite containing CaZe had most superior heat resistance, electrical insulation, and flexural strength, though in the lastly listed property it ranked next to the GF‐filled composite. The linear expansion coefficient of the composite containing CaZe was as low as almost isotropic. The reasons of obtaining these excellent properties were thought to be as follows: (1) CaZe could finely be dispersed in the phenolic resin to bring good impregnation. (2) The surface chemical and physical interaction between the resin and CaZe was higher than that between the resin and the other fillers. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Properties of molded soy protein isolate plastics
Authors: Wang Hao , Jiang Lin , Fu Lei 
Published: August 2007

AbstractThermal property of soy protein isolates (SPI) was studied with differential scanning calorimetry and thermogravimetric analysis. The weight loss of pure SPI is about 300°C. The glass transition temperature (Tg) is above 200°C. The best molding temperature of glycerin plasticized SPI plastics were then given. It is between 125 and 140°C. Subsequently the special property of molded SPI plastics was investigated. Results show that the atmosphere humidity affects the mechanical property and thermal property of SPI plastics. With the increasing humidity, the tensile strength decreases. While the elongation at breakage and peak area of the differential scanning calorimetry curve increases. At high temperature even at 140°C the molding temperature SPI plastics still have tensile strength though it decreases with the increasing test temperature while elongation at breakage increases. Dynamic mechanic thermal analysis test show that the storage modulus decreases with the rising temperature. The mechanical loss peak appears at lower temperature with the increasing amount of glycerin content. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
In situ observation of plerosphere/polypropylene composites in the tensile test
Authors: Zheng Yanhong , Shen Zhigang , Wang Mingzhu , Ma Shulin , Xing Yushan 
Published: August 2007

AbstractToughness, strength, and rigidity of the composites can be improved simultaneously by filling plerosphere particles into polypropylene (PP). The mechanism of improving the mechanical properties of the composites is studied on the basis of the energy dissipation theory. By using scanning electron microscopy (SEM), the crack initiation, propagation, and termination on the plerosphere/PP composites are investigated by in situ tensile test. Observation results show that the particles can effectively lead to a number of microcracks instead of the breaking crack. These microcracks formation consumes tremendous energy. As a result, the toughness and strength of the polymer can be improved. Results of the in situ SEM observation and analysis to the dynamic process supply effective test evidence for the toughening mechanism of the plerosphere/PP composite on the basis of the energy dissipation theory. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Calcitonin Gene‐Related Peptide: A Marker for Putative Primary Afferent Neurons in the Pig Small Intestinal Myenteric Plexus?
Authors: Wolf Matthias , Schrödl Falk , Neuhuber Winfried , Brehmer Axel 
Published: August 2007

AbstractFor years, calcitonin gene‐related peptide (CGRP) has been used as a marker peptide for Dogiel type II neurons, putative intrinsic primary afferent neurons, in the pig enteric nervous system. Recently, some studies showed CGRP‐positive neurons displaying distinctly different shapes. The aims of this study were to evaluate (1) the proportion of myenteric type II neurons that contain CGRP and (2) the proportion of myenteric CGRP‐positive neurons that display type II vs. non–type II morphologies and to conclude if this peptide could be suited as a marker for type II neurons. For this purpose, nine myenteric whole‐mounts (each one from duodenum, jejunum, and ileum, respectively, derived from three pigs) were triple‐immunostained for CGRP, neurofilaments (NF), and choline acetyl transferase (ChAT). Each whole‐mount was evaluated twice. First, 50 NF‐stained type II neurons were selected randomly and their coreactivities for CGRP and ChAT were observed. Second, 50 CGRP‐positive neurons were located randomly and their NF morphology and ChAT coreactivity were observed. Altogether, 92% of all type II neurons investigated displayed CGRP immunoreactivity, whereas 94.9% of all CGRP‐reactive neurons recorded displayed type II morphology. We observed three further shapes of CGRP‐positive neurons: 7 type V neurons (all were ChAT‐positive; mainly in the ileal whole‐mounts), 6 type I–like neurons (all were ChAT‐positive), and 14 type III–like neurons (mostly ChAT‐negative; mainly in duodenal and jejunal specimens). We conclude that CGRP‐antibodies can be used as markers for type II neurons in the pig small intestinal myenteric plexus in quantitative studies but it should be kept in mind that up to one‐tenth of CGRP‐reactive neurons may be non–type II neurons. In case of single cell evaluation, CGRP‐immunoreactivity alone is not suited as a marker. In such cases additional, morphological analysis is necessary. Anat Rec, 290:1273‐1279, 2007. © 2007 Wiley‐Liss, Inc.
1‐Cinnamyl‐4‐(2‐methoxyphenyl)piperazines: Synthesis, Binding Properties, and Docking to Dopamine (D2) and Serotonin (5‐HT1A) Receptors
Authors: Penjišević Jelena , Šukalović Vladimir , Andrić Deana , Kostić‐Rajačić Sladjana , Šoškić Vukić , Roglić Goran 
Published: August 2007

AbstractClinical properties of atypical antipsychotics are based on their interaction with D2 dopamine receptor and serotonin 5‐HT1A and 5‐HT2A receptors. As a part of our research program on new antipsychotics, we synthesized various derivatives of 1‐cinnamyl‐4‐(2‐methoxyphenyl)piperazines, and evaluated their affinities for D2, 5‐HT1A, 5‐HT2A, and adrenergic (α1) receptors using radioligand‐binding assays. In addition, we performed docking analysis using models for the D2 and 5‐HT1A receptors. All compounds exhibited low to moderate affinity to 5‐HT1A and 5‐HT2A receptors, high affinity to the D2 receptor and large variability in affinities for the α1 receptor. Docking analysis indicated that the binding to D2 and 5‐HT1A receptors is based on (i) interaction between protonated N1 of the piperazine ring and various aspartate residues, (ii) hydrogen bonds between various moieties of the ligand and the residues of threonine, serine, histidine or tryptophane, and (iii) edge‐to‐face interactions of the aromatic ring of the arylpiperazine moiety with phenylalanine or tyrosine residues. Docking data for the D2 receptor can account for the binding properties obtained in binding assays, suggesting that the model is reliable and robust. However, docking data for the 5‐HT1A receptor cannot account for actual binding properties, suggesting that further refinement of the model is required.
Pharmacokinetic Profile of Atenolol Aspirinate
Authors: Montes‐Gil Ana C. , Zanfolin Marcos , Okuyama Cristina E. , Lilla Sergio , Alves Delma P. , Santagada Vincenzo , Perissutti Elisa , Lavecchia Antonio , Fiorino Ferdinando , Severino Beatrice , Caliendo Giuseppe , Priviero Fernanda B. M. , Mendes Gustavo D. , Donato Jose L. , Nucci Gilberto de 
Published: August 2007

AbstractWe report microwave‐assisted synthetic routes, the pharmacokinetic profile along with results from ulcerogenicity and mutagenicity studies of atenolol aspirinate, and an already described derivative, in which acetyl salicylic acid (aspirin®) was connected to atenolol by an ester linkage. Atenolol aspirinate was stable towards aqueous hydrolysis but rapidly hydrolyzed in plasma (t1/2= 7.6 min). The results showed that the rapid and complete hydrolysis generates atenolol salicylate, which assumes a conformation stabilized by two intramolecular H‐bonds, avoiding its further hydrolysis to salicylic acid and atenolol.
Synthesis of 2‐Substituted‐7‐heptyloxy‐4,5‐dihydro‐[1,2,4]‐triazolo[4,3‐a]quinolin‐1(2H)‐ones with Anticonvulsant Activity
Authors: Wei Cheng‐Xi , Li Fu‐Nan , Zhao Long‐Xuan , Zhao Li‐Ming , Quan Zhe‐Shan 
Published: August 2007

AbstractA series of 2‐substituted‐7‐heptyloxy‐4,5‐dihydro‐[1,2,4]triazolo[4,3‐a]quinolin‐1(2H)‐ones was synthesized. The anticonvulsant effect and neurotoxicity of the compounds were calculated with maximal electroshock (MES) test, subcutaneous pentylenetetrazole (sc‐PTZ), and rotarod tests with intraperitoneally injected mice. Among the synthesized compounds, 2‐propionyl‐7‐heptyloxy‐4,5‐dihydro‐[1,2,4]triazolo[4,3‐a]quinoline‐1(2H)‐one 4b was the most active one and also had the lowest toxicity. In the anti‐MES potency test, it showed median effective dose (ED50) of 8.2 mg/kg, median toxicity dose (TD50) of 318.3 mg/kg, and the protective index (PI) of 39.0 which is much greater than the PI of the reference drugs phenytoin and carbamazepine.
CD19 hyperexpression augments Sle1‐induced humoral autoimmunity but not clinical nephritis
Authors: Shi Xiaoyan , Xie Chun , Chang Sooghee , Zhou Xin J. , Tedder Thomas , Mohan Chandra 
Published: August 2007

AbstractObjectiveB cell hyperactivity is a common denominator in murine and human systemic lupus erythematosus. Some susceptibility genes in lupus are associated with B cell hyperactivity, but others are clearly not. While the Sle1 lupus susceptibility locus of NZM2410/NZW origin leads to chromatin‐focused autoimmunity, genetically engineered overexpression of CD19 leads to “generalized” B cell hyperactivity. We undertook this study to determine the degree to which generalized B cell hyperactivity can amplify lupus pathogenesis.MethodsTo elucidate the impact of generalized B cell hyperactivity on Sle1‐triggered autoimmunity, B6 mice bearing the human CD19 transgene were rendered congenic for the Sle1z genetic locus and phenotyped for serologic, cellular, and pathologic evidence of lupus.ResultsAs expected, B6.Sle1.hCD19Tg/Tg mice, homozygous at Sle1 and bearing the hCD19 transgene, exhibited high levels of IgM and IgG anti‐DNA/antiglomerular autoantibodies, skewed B cell subsets, and profoundly activated B and T cells. Despite exhibiting glomerular IgM, IgG, and complement deposits, these mice did not exhibit accelerated mortality or any clinical evidence of renal dysfunction.ConclusionGeneralized B cell hyperactivity may augment humoral autoimmunity, but this may not suffice to engender end‐organ disease in lupus. These findings allude to the presence of an additional distal checkpoint that dissociates pathogenic autoantibody formation and renal immunoglobulin deposition from the progression to clinical nephritis in lupus.