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Competition in research has led to the emergence of new regional spaces and interorganizational arrangements, designed to improve their participants' visibility, at the crossroads of regional systems and global exchanges. This article investigates the determinants of the formation of interregional scientific alliances through the in-depth case study of a federation of research laboratories in green chemistry in western France. Working from bibliometric and qualitative data and using a network analysis approach to evidence interurban network failures in this scientific field, we examine the federation's geographical scope. We highlight the decisive role of (1) the spatial organization of the field (structure effect), (2) interpersonal ties between consortium members (network effect) and (3) national scientific guidelines and incentives (policy effect). We propose a novel mixed-method approach to understand interregional alliances and defend its potential to uncover the importance of interregional institutional arrangements in prompting interurban knowledge exchanges. [ABSTRACT FROM AUTHOR]

This paper studies the crate sizing problem to predetermine optimal standard packaging crate sizes for a demand of assorted sizes of products to minimise space and costs. The crate sizing problem is a real world logistics scenario faced by an existing multinational corporation in the applied chemistry industry. Customer demands come in a mix of rolls to be packaged in individual crates and then shipped in shipping containers from plants to customers. Firstly, a linear crate length optimisation model is introduced with the objective to minimise the total loss of extra space inside the crates for a given distribution of customer demands. In order to take inventory costs of crates into consideration, a second problem is introduced to both find the optimal number of crate types and the corresponding lengths such that the total costs of packaging and inventory are minimised. The latter problem is first formulated as a non-linear optimisation model and then solved using dynamic programming approach to balance the trade-off between the number of crate types and the penalty cost for space wastage inside the crates. [ABSTRACT FROM PUBLISHER]

Between 1920 and 1922, the University of Bristol biochemist, Maximilian Nierenstein, published four papers in a series exploring the structure of catechin in the Journal of the Chemical Society. The Society then abruptly refused to accept any more of his papers on catechin, or any other subject. It provided him with no reasons for the embargo until 1925. It then transpired that Nierenstein was boycotted because it was deemed that he had not responded adequately to criticisms of his work made by his rival in catechin research, the German natural products chemist, Karl Freudenberg. It was not until 1929 that, as a result of a petition by a group of his former Bristol pupils and friends, that Nierenstein was again permitted to publish in the Society's journal. The paper explores the Chemical Society's treatment of Nierenstein in detail, sheds new light on his career and his reaction to the Society's unprecedented boycott, examines some of the structural chemistry involved in the disputes, and discusses whether Nierenstein's research deserves the label of 'bad science'. [ABSTRACT FROM AUTHOR]

Perchlorate is a low molecular weight highly soluble anion. It occurs naturally in the environment, primarily near potash deposits and in arid regions. The determination of perchlorate in human milk is of interest in vulnerable populations such as infants and pregnant women. In this study, a sensitive and selective isotope dilution ion chromatography/tandem mass spectrometry (ID IC-MS/MS) method was developed and validated for the determination of perchlorate in human milk samples collected from the Maternal-Infant Research on Environmental Chemicals (MIREC) Study. The limit of detection (LOD) was 0.27 µg·kg−1 for human milk. A total of 439 human milk samples were analysed with measurable levels of perchlorate in most of the milk samples, and the mean value was 7.62 ± 32.7 µg·kg−1. This project provided important information related to perchlorate levels in human milk collected across Canada and the extent to which pregnant women and their infants may be exposed to perchlorate. A dietary exposure assessment was also conducted in infants based on the measured values in human milk. The mean perchlorate probable daily intakes (PDIs) for infants consuming human milk were 0.31 ± 0.07 μg/kg bw/day for infants under 1 year and 0.17 ± 0.10 μg/kg bw/day for infants between 1 and 3 years old. None of the estimates exceeded the FAO/WHO provisional maximum tolerable daily intake (PMTDI) of 10 μg/kg bw/day. [ABSTRACT FROM AUTHOR]

This paper publishes, for the first time, Humphry Davy's June 1798 "An Essay on Heat and the Combinations of Light" written in Penzance. It is the manuscript that he sent to Thomas Beddoes which secured for him the position of Superintendent of the Medical Pneumatic Institution in Bristol while aged only nineteen. It is thus a crucial document that increases our understanding about how Davy made that move from Cornwall to Bristol, without which it is highly unlikely that he would have followed the spectacular career trajectory that he did. The "Essay" provides new insights into Davy's very early chemical reading (especially the English translations of Antoine Fourcroy's Elémens d'histoire naturelle et de chimie), the extent to which Davy read this (and other texts) in French, the chemical apparatus he used, the experiments he made and the development and retraction of his theory of phosoxyd (later phosoxygen). [ABSTRACT FROM AUTHOR]

Aiming at the problem that the transformer substation intelligent detection of vehicles in the process of moving away from the planning path, based on the four-wheel model vehicle, this paper proposes a fuzzy adaptive PID path tracking control method based on optimal lateral deviation. Firstly, the kinematic model and the equation of the linear 2-DOF of the vehicle are established by taking the front wheel steering angle of the model vehicle as the input of the control system. Secondly, the linear quadratic regulator (LQR) is introduced to minimize the transverse tracking error between the model vehicle and the expected path. Finally, the control parameters of the fuzzy PID are updated with the lateral deviation and the variation rate of the deviation, and the front wheel steering angle of the Vehicle is adjusted adaptively to realize the stable tracking of the desired path. The simulation results show that the tracking error of the proposed path tracking control method is concentrated between -0.08m and +0.08m, and the desired path can be better tracked. [ABSTRACT FROM AUTHOR]

Microfluidics is used in a broad range of applications, from biology and medicine to chemistry and polymer science, because this versatile platform enables rapid and precise repeatability of measurements and experiments on a relatively low-cost laboratory platform. Despite wide-ranging uses, this powerful research platform remains under-utilized by the atmospheric aerosol science community. This review will summarize selected microfluidic concepts and tools with potential applications to aerosol science. Where appropriate, the basic operating conditions and tunable parameters in microfluidics will be compared to typical aerosol experimental methods. Microfluidics offers a number of advantages over larger-scale experiments; for example, the small volumes of sample required for experiments open a number of avenues for sample collection that are accessible to the aerosol community. Filter extraction, spot sampling, and particle-into-liquid sampling techniques could all be used to capture aerosol samples to supply microfluidic measurements and experiments. Microfluidic concepts, such as device geometries for creating emulsions and developments in particle and droplet manipulation techniques will be reviewed, and current and potential microfluidic applications to aerosol science will be discussed. Copyright © 2018 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

Chemical pour point depressant modification is an important means to reduce pour point and viscosity of waxy crude oil. In recent years, the research on the modification of pour point depressants has made a great progress. This paper summarizes the types of novel nano-pour point depressants, preparation methods, evaluation methods, mechanism of action and influencing factors. The development of the pour point depressant and the future outlook made a brief summary. [ABSTRACT FROM AUTHOR]

The author looks into the future for the history of alchemy and chemistry, in commemoration of the journal's eightieth anniversary. It reflects on the number of studies on technical problems in the intellectual history of chemistry and special issues that were based on conferences organised by John Perkins and Antonio Garcia-Belmar. It also examines the collaborations among chemists, historians, classicists, philologists, and archaeologists.

Attention to the history of chemistry can help us recognise the characteristics of chemistry that have helped to maintain it as a separate scientific discipline with a unique identity. Three such features are highlighted in this paper. First, chemistry has maintained a distinct type of theoretical thinking, independent from that of physics even in the era of quantum chemistry. Second, chemical research has always been shaped by its ineliminable practical relevance and usefulness. Third, the lived experience of chemistry, spanning the laboratory, the classroom and everyday life, is distinctive in its multidimensional sensuousness. Furthermore, I argue that the combination of these three features makes chemistry an exemplary science. [ABSTRACT FROM AUTHOR]

We are pleased to present a second annual issue highlighting a previous year’s literature on biotransformation and bioactivation. Each contributor to this issue worked independently to review the articles published in 2016 and proposed three to four articles, which he or she believed would be of interest to the broader research community. In each synopsis, the contributing author summarized the procedures, analyses and conclusions as described in the original manuscripts. In the commentary sections, our authors offer feedback and highlight aspects of the work that may not be apparent from an initial reading of the article. To be fair, one should still read the original article to gain a more complete understanding of the work conducted. Most of the articles included in this review were published in Drug Metabolism and Disposition or Chemical Research in Toxicology, but attempts were made to seek articles in 25 other journals. Importantly, these articles are not intended to represent a consensus of the best papers of the year, as we did not want to make any arbitrary standards for this purpose, but rather they were chosen by each author for their notable findings and descriptions of novel metabolic pathways or biotransformations. I am pleased that Drs. Rietjens and Dalvie have again contributed to this annual review. We would like to welcome Grover P Miller as an author for this year’s issue, and we thank Tom Baillie for his contributions to last year’s edition. We have intentionally maintained a balance of authors such that two come from an academic setting and two come from industry. Finally, please drop us a note if you find this review helpful. We would be pleased to hear your opinions of our commentary, and we extend an invitation to anyone who would like to contribute to a future edition of this review. This article is dedicated to Professor Thomas Baillie for his exceptional contributions to the field of drug metabolism. [ABSTRACT FROM AUTHOR]

In the paper presented are the author's subjective views on the most important achievements in the stereochemistry of organic sulfur compounds, which, as an object of research, has more than 100-year history. Prospects for further development are also mentioned. [ABSTRACT FROM PUBLISHER]

The article discusses a research investigating preparation of novel 3-fluorophenyl triazolothiadiazoles and triazolothiadiazines.

The article discusses a research conducted on practical synthesis of lycopene.

The article discusses a research conducted for improved large-scale one-pot synthesis of pure doripenem hydrate (S-4661).

The article discusses a research proposing a novel method of preparing (S)-5-fluoro-3-phenyl- 2-[1-(9H-purin-6-ylamino)propyl]-3H-quinazolin-4- one.

The research conducted to analyse efficient and green Ritter reaction for the synthesis of Nitrogen-(tert-Butyl)- and Nitrogen-benzylamides from tert-butyl and benzyl acetates.

Over the last two decades, various themes inherent in the responsible conduct of research (RCR) in chemistry have been brought to light through prominent cases of research misconduct. This article will describe a few of these cases especially through the lens of social media such as blogs and Twitter. A case will be made that these wholly novel modalities of online discussion are now complementing, and in some cases even circumventing some of the limitations of traditional peer review in chemistry. We present in detail our evaluation of three recent cases of RCR along with several other social media illustrations. These cases have been selected to be representative and showcase several of the most prominent issues at the intersection of traditional and social-media based peer review. In each case, basic details are presented along with a brief discussion of the underlying issues--readers interested in deeper analysis of each subject are referred to a collection of relevant articles and websites. This perspective focuses on the most important RCR issues that have arisen in the past decade, a time which we believe coincides with the serious participation of the scientific community in general, and the chemistry community in particular, in social media-based, citizen-enabled peer-review. A discussion of important trends in RCR in the age of social media, outstanding developments in this area, and questions of enduring interest for the near future concludes the article. [ABSTRACT FROM AUTHOR]

Journalists who cover scientific research, including chemistry research, have an obligation to report on alleged cases of research misconduct when knowledge of these surface. New Government definitions of research misconduct, beginning in the late 1990s with the Clinton Administration, have helped scientists, policymakers, as well as journalists sort out and make sense of alleged research misconduct. Journalistic reporting on research misconduct includes many challenges: gathering information from sources who are intimidated or afraid to speak, strict adherence to journalist ethics that take on a new dimension when careers, reputations, and research funding are at stake; efforts by government and institutional bureaucrats to dampen or thwart legitimate news coverage. The Internet, blogging, and social media have added still more complexity and ethical quandaries to this blend. The author, News Editor of Chemical & Engineering News published by the American Chemical Society, provides examples from his own career and that of colleagues. He suggests that an enhanced spirit of understanding and cooperation between journalists and members of the scientific community can lead to avenues of open discussion of research misconduct--discussions that might prevent and mitigate the very real damage caused by bad actors in science who betray themselves, their peers, and the body of modern day scientific knowledge when they make the decision to march into the darkness of dishonesty, plagiarism, or falsification. [ABSTRACT FROM AUTHOR]

A survey on credit issues and related "responsible conduct of research" (RCR) behaviors was conducted with academic chemists in Ph.D. granting institutions in the U.S. Six hundred faculty members responded. Fifty percent of the respondents reported not receiving appropriate credit for contributions they had made to projects the results of which had been published, including when they themselves were students. Thirty percent of these individuals discussed this lack of credit with the "offending" individual, and as a consequence of those discussions, a small percentage of individuals were provided either co-authorship or an acknowledgment. The majority who did not enter into a discussion with the "offending" individual reported two primary reasons for not doing so: that they "could not imagine any good coming from such a conversation" and "I was afraid of being in a compromised situation." A discussion of relationship asymmetry in the academic setting is provided. Confronting one's colleague regarding credit is compared with whistleblowing, and the possible consequences of blacklisting are discussed. A number of recommendations for minimizing authorship disputes are provided. [ABSTRACT FROM AUTHOR]

This article makes a case for a positive role of tension in the creative process in chemistry. I begin with an argument that there is an inherent tension in what makes molecules interesting--their positioning along various polar axes. One of these, the age-old differentiation between useful (to society and for personal profit) commercialization and pure understanding of molecules and their reactions is characteristic. The question of whether there are any bad molecules then leads me to ethical concerns in chemistry, and a particular working out of these in interactions of chemists in the Middle East. An analysis is made of the special tensions involved in publishing, especially in citation ethics; chemists publish a lot, so this is situation ethics worked out on a daily basis. I then find in the literature of psychology good evidence for the positive value of moderate stress in stimulating creativity. It is obvious that too much tension leads to distress, and there are some institutional aspects of chemistry that do not come out well here. But all in all, the dynamic middle is alive, and it leads to good new science. [ABSTRACT FROM AUTHOR]

This article discusses the ethical issues unique to the science and practice of chemistry. These issues arise from chemistry's position in the middle between the theoretical and the practical, a science concerned with molecules that are of the right size to directly affect human life. Many of the issues are raised by the central activity of chemistry-- synthesis. Chemists make thousands of new substances each year. Many are beneficial, but others are threats. Since the development of the chemical industry in the nineteenth century, chemistry has contributed to the deterioration of the environment but has also helped to reduce pollution. Finally, we discuss the role of codes of ethics and whether the current codes of conduct for chemists are adequate for the challenges of today's world. [ABSTRACT FROM AUTHOR]

An algorithm to compute vibronic spectra of harmonic surfaces including Dushinsky rotation and Hertzberg–Teller terms is described. The method, inspired by thermo field dynamics, maps the thermal density matrix onto the vacuum state and uses the time-dependent coupled cluster ansatz to propagate it in time. In the Franck–Condon approximation where the dipole matrix elements are taken to be constants, this reduces to the auto correlation function of the new vacuum. In the Hertzberg–Teller approximation, the full time evolution operator is needed. This too is governed by a closed set of equations. The theoretical development is presented along with an application to anthracene. [ABSTRACT FROM AUTHOR]

This review highlights the methods used for the synthesis of 3-oxo-N-(pyridin-2-yl)butanamide compounds. The reactivity and synthetic importance are investigated. In this context, recent progress in the synthesis and use of 3-oxo-N-(pyridin-2-yl)butanamide as precursors for heterocyclic compounds is reviewed. The synthetic routes for preparation of 3-oxo-N-(pyridin-2-yl)butanamide are based on the reaction of diketene with aromatic primary amine and reaction of 2-aminopyridine withβ-keto-t-butylthioester or ethylacetoacetate. The bibliography includes 73 references. [ABSTRACT FROM PUBLISHER]

This paper focuses on the internal organization and dynamics of the Institute Bento da Rocha Cabral (IRC) in Lisbon, a privately-funded institution devoted to biomedical research, from the particular vantage point of its laboratory of biochemistry; in particular, the process through which the institution turned from medically-related to chemically-related research in the period spanning from 1925 to 1953. The history of the IRC raises interesting questions regarding the social politics of science as it materialized the desire of leading physicians of the Faculty of Medicine of Lisbon to create proper physical facilities for medically-related scientific research. We argue that the process which led to the creation of the IRC coincided with the gradual professional and political ascendance of physicians in Portuguese society initiated in the late nineteenth century, and is closely associated with Portuguese republicanism and the process of Lisbon becoming the scientific capital. [ABSTRACT FROM AUTHOR]

The development of new strategies for the synthesis of small-sized heterocycles has remained a highly attractive but challenging proposition. An overview of the application of microwave irradiation in nitrogen-containing fused five-membered heterocyclic compounds synthesis is presented, focusing on the developments in the past 5–10 years. This contribution covers the literature concerning the total synthesis of fusedN-heterocycles. [ABSTRACT FROM AUTHOR]

The development of universities and technical schools in nineteenth century Switzerland is commonly assumed to be similar to the development of comparable schools in Germany. To a large extent this is correct, but there are subtle differences in the founding and organization of Swiss institutions that are reflective of the Swiss national and local cantonal contexts. In the case of Zürich, the specific local political and financial conditions underlying the formation of the University of Zürich, the Zürich Cantonal School and the Swiss Federal Polytechnic resulted in a complex set of dual appointments and shared facilities that were absent at comparable chemical laboratories at German universities. This essay outlines the origins of these complex relationships under Carl Löwig (1833–1853) and Georg Städeler (1853–1870) and follows in more detail the complex career path of Johannes Wislicenus in Zürich from his appointment asPrivatdozentin 1860 to his appointment as Director of the Polytechnic in 1871. Wislicenus’ career path illustrates the institutional context of chemistry in Zürich and shows how this context, including the roles of cantonal and federal support, and the physical constraints created by shared laboratory facilities, shaped chemical research and instruction in Zürich. [ABSTRACT FROM PUBLISHER]

Some soft magnetic metallic glasses are considered for use in magnetic cores of accelerator radio frequency cavities. Due to losses of the circulating ion beam, they may be exposed to irradiation by different ions at different energies. This paper presents data and review results of irradiation experiments concerning the influence of high-energy heavy ions on magnetic susceptibility of VITROPERM®-type metallic glasses. Samples of the VITROPERM® magnetic ribbons were irradiated by Au, Xe and U ions at 11.1 MeV/A (per nucleon) and 5.9 MeV/A, respectively. Irradiation fluences from 1 × 1011up to 1 × 1013ions/cm2were applied. In case of the Au and U ions, the total fluence was accumulated in one beamtime, whereas two separate beamtimes were used to accumulate the final fluence in case of the Xe ions. Relative change in the samples’ magnetic susceptibility after and before irradiation was evaluated as a function of the irradiation fluence. The irradiation experiments were performed with the UNILAC accelerator at GSI Helmholtzzentrum für Schwerionenforschung GmbH. They were simulated in SRIM2010 in order to obtain ionization densities (electronic stopping, dE/dx) and dpa (displacements per atom) caused by the ion beams in the sample material. This paper focuses mainly on the results collected in experiments with the Xe ions and compares them with data obtained in earlier experiments using Au and U ions. Radiation hardness of VITROPERM® is compared with radiation hardness of VITROVAC® that was studied in previous experiments. The VITROPERM® samples showed less drop in magnetic susceptibility in comparison with the VITROVAC® ones, and this drop occurred at higher fluences. This indicates higher radiation hardness of VITROPERM® compared with VITROVAC®. In addition, heavier ions cause bigger change in magnetic susceptibility than the lighter ones. The effect can be roughly scaled with electronic stopping, which suggests that the main mechanism of radiation damage is associated with swift electrons generated in the material via ionization by primary heavy ions. [ABSTRACT FROM PUBLISHER]

Thermoluminescence (TL) of synthetic quartz exposed to beta irradiation following implantation with 60 keV N+ions at fluences ranging between 1 × 1014and 5 × 1015 ions/cm2is reported. The glow curve measured at 5°C/s typically consists of a prominent peak near 110°C, studied in this work, and minor glow peaks at around 130°C and 190°C. The TL intensity of the main peak increased both with implantation and with fluence of implantation. The dependence of the intensity on the heating rate and fluence suggests that the implantation introduces new defects that may possibly act as recombination centres. The increase in TL intensity with the heating rate exhibited by implanted samples has been observed in other luminescence materials. This anti-quenching phenomenon has been described as a competition effect between multiple luminescence pathways in luminescence materials. Kinetic analysis of the main glow peak using the initial rise, various heating rate and glow-curve deconvolution methods shows that the activation energy of the main peak is about 0.7 eV with no systematic change due to ion fluence. [ABSTRACT FROM PUBLISHER]

The development of new strategies for synthesis of medium-sizedO-heterocycles has remained a highly attractive but challenging proposition. An overview of the application of microwave irradiation in oxygen-containing seven- and higher-membered heterocyclic compounds synthesis is presented, focusing on the developments in the past 5–10 years. This contribution covers the literature concerning the total synthesis ofO-heterocycles. The literature data are summarized based on the size of cycles. [ABSTRACT FROM AUTHOR]

Patterns of collaboration and co-authorship in chemical science from the 1920s to the 1960s are examined with an eye to frequency of co-authorship and differences in allocation of credit during a period of increasing team research and specialization within chemical research groups. Three research leaders in the cross-disciplinary and cutting edge field of X-ray crystallography and molecular structure are the focus of this historical study within a framework of sociological literature on different collaborative patterns followed by eminent scientists. The examples of Michael Polanyi in Berlin and Manchester, Linus Pauling in Pasadena, and Dorothy Crowfoot Hodgkin in Oxford demonstrate the need to de-centre historical narrative from the heroic 'he' or 'she' to the collaborative 'they.' These cases demonstrate, too, the roles of disciplinary apprenticeships, local conditions, and individual personalities for historical explanation that transcends universal generalizations about scientific practice, material culture, and sociological trends. [ABSTRACT FROM AUTHOR]

Patterns of collaboration and co-authorship in chemical science from the 1920s to the 1960s are examined with an eye to frequency of co-authorship and differences in allocation of credit during a period of increasing team research and specialization within chemical research groups. Three research leaders in the cross-disciplinary and cutting edge field of X-ray crystallography and molecular structure are the focus of this historical study within a framework of sociological literature on different collaborative patterns followed by eminent scientists. The examples of Michael Polanyi in Berlin and Manchester, Linus Pauling in Pasadena, and Dorothy Crowfoot Hodgkin in Oxford demonstrate the need to de-centre historical narrative from the heroic 'he' or 'she' to the collaborative 'they.' These cases demonstrate, too, the roles of disciplinary apprenticeships, local conditions, and individual personalities for historical explanation that transcends universal generalizations about scientific practice, material culture, and sociological trends. [ABSTRACT FROM AUTHOR]

The field of chemoinformatics has developed from different roots, starting in the 1960s. These branches have now merged into a scientific discipline of its own, exchanging ideas and methods across different areas of chemistry. In the last 40 years chemoinformatics has achieved a lot. Without access to the databases in chemistry developed with chemoinformatics methods, modern chemical research would not be able to work at its present high level of competence. However, there are quite a few challenges, such as drug design and understanding the effect of chemicals on human health and on the environment, as well as furthering our knowledge of chemistry and of biological systems, that can benefit from a more intensive use of chemoinformatics methods. Approaches to meet these challenges will be briefly outlined. All this emphasizes that chemoinformatics has matured into a scientific discipline of its own that reaches out to many other chemical fields and will increase in attractiveness to students and researchers. [ABSTRACT FROM AUTHOR]

Solid-phase organic synthesis is a rapidly expanding area of synthetic chemistry which is being widely exploited in the search for new medicinally important compounds using combinatorial techniques. In recent decades, a large number of reports related to solid-phase synthesis of heterocycles have appeared because of the wide variety in their biological activity. In this review, we report the important role of solid-phase synthesis in the synthesis of oxygen-bearing heterocycles. [ABSTRACT FROM AUTHOR]

Methods for the preparation of various fused thiazolotriazoles were reviewed here for the first time. The main two isomers of fused thiazolotriazoles are thiazolo[3,2-b][1,2,4]triazole and thiazolo[2,3-c][1,2,4]triazole. Some medicinal applications of thiazolotriazoles are reported. [ABSTRACT FROM PUBLISHER]

The elements that for simplicity we call “true” firmly occupy their places in the periodic table of the elements. By contrast, there are the elements that we call “false.” These elements, difficult to systematize, occupied, for time periods more or less extended, a place within the periodic classification. Every desire has its own plan, and every plan its own point of departure and arrival. Committed to making some sense out of the incessant coupling of molecules that combine and break up, chemists have tended to name the fundamental substances of matter, the elements, so that their research might be better remembered by posterity and confer on their deeds a kind of human immortality. [ABSTRACT FROM AUTHOR]

Just five British students of chemistry studied with Robert Wilhelm Bunsen (1811-1899) at Marburg in the 1840s, and over a hundred with him at Heidelberg between 1852 and 1888. These pupils were largely responsible for transmitting knowledge of Bunsen's instrumental innovations such as gasometry and spectroscopy to Britain. They also voiced Bunsen's merits as an outstanding teacher. The paper traces (where possible) their careers as researchers, teachers, and industrialists. A list of Bunsen's students is included in the form of a Biographical Register. [ABSTRACT FROM AUTHOR]

Franciscus dele Boë (1614-1672), known as Sylvius, was one of the foremost chymical physicians of the mid-seventeenth century. He developed a highly influential and equally controversial theory of chymistry and physiology based on the interaction of acids and alkalis, taught students from across Europe, and performed and guided experimental research on digestion, glands, respiration, and the motion of the heart. Throughout his work, Sylvius grounded his knowledge of the acid and alkali chymical principles in the practice of tasting. In this paper, I expand our knowledge of Sylvius's chymistry and recover the surprising extent and significance of his use of his senses to assay chymical substances. I compare the uses of taste in more traditional Galenic medicine and the emerging chymistry in order to argue that Sylvius's reliance on taste grew directly out of his favoured chymical traditions. Looking to the broader context of philosophical medicine also allows us to see Sylvius's explicit commitment to Cartesian matter theory as an ideal: a metaphysical dream that he accepted yet criticised for its poor fit with the hard work and bodily experience central to proper chymistry and medicine. [ABSTRACT FROM AUTHOR]

Isophorone diisocyanate is used to react with poly (propylene oxide) of 1000 number average relative molecular mass in different temperatures. In situ FT-IR is used to monitor the reaction to work out rate constant, Arrhenius equation, and Eyring equation. The polymerization reaction has been found to be a second-order reaction, and rate constant seems different between the first stage and second stage at 5°∼10°C. However, it is surprising that the reactivity difference disappeared and the reaction rate merges when reaction temperature increases. The 1/(1 − p)∼t curves become straight at 15°∼25°C. Finally, the activation energy (E a), activation enthalpy (ΔH), and activation entropy (ΔS) for the polymerization are calculated, which are 73.9 KJ · mol−1, 71.6 KJ · mol−1, and −21.0 J · mol−1 · k−1, respectively. [ABSTRACT FROM AUTHOR]

The article presents a study on the effects of N-bromosuccinimide (NBS) oxidation of E-3-benzylidenechromanones to 3-benzoylchromones and 3-(α-Hydroxybenzyl)chromones. The study involves E-3-benzylideneflavanones which have two molar eqivalents of NBS, wherein oxidation gave 3-benzoylchromones with around 40% of unconverted starting materials. The study shows that the NBS oxidation of E-3-benzylidenechromanones is a good addition to its many applications. Furthermore, several tables which show data on the NBS oxidation of E-3-benzylidenechromanones, 3-(α-Hydroxybenzyl)chromones, and E-3-benzylideneflavanones are presented.

Founded in 1919, the International Union of Pure and Applied Chemistry (IUPAC) was successor to the International Association of Chemical Societies (IACS), which had been founded eight years earlier at the initiative of Albin Haller. The statutes of the IUPAC (like those of the IACS) were written in French, and it was agreed that the IUPAC's administrative headquarters should be in Paris. With these arrangements in place, the role of French chemists generally, and of Haller and Charles Moureu in particular, assumed crucial importance. In 1927, on the occasion of the centenary of Marcelin Berthelot's birth, plans were laid for an international centre for chemistry in Paris, soon to be known as the Maison de la Chimie. From the start, the Maison de la Chimie project was led by the French, most conspicuously by Jean Gérard, general secretary of the Société de chimie industrielle and of the IUPAC. Gérard's contribution to a number of national and international committees, notably for scientific documentation, left an enduring legacy. The years between 1918 and 1927, especially 1918-1919, were decisive for the rebuilding, on many fronts, of international networks embracing individuals and institutions recently separated by war. This article examines the particular case of chemistry, with reference to this wider context and to the widely shared determination to fashion an organisation that would transcend national boundaries and embrace both the pure and the applied aspects of the discipline. [ABSTRACT FROM AUTHOR]

The purpose of this work is to translate some of Robert Boyle's chemical experiments into the terms of modern chemistry. Most of the reactions involve sensible qualities, since there are on it considerable helpful tracking descriptions like heating, hissing, colour changing, etc. For a long time in the history of science, this procedure was seen as an exercise in anachronism which should be avoided at all costs. Recently many scholars have demonstrated that chemical translation can assist with historical work instead of causing confusion, and it may be very useful as a tool for the history of chemistry and for reproducing past chemical experiments. [ABSTRACT FROM AUTHOR]

Managing the potential environmental risks of nanoparticles requires methods to link nanoparticle properties with macro-scale risks. This study outlines challenges in exposure modeling of nanoparticles in aquatic environments, such as the role of natural organic matter, natural colloids, fractal dimensions of agglomerates, coatings and doping of particles, and uncertainties regarding nanoparticle emissions to aquatic environments. The pros and cons of the exposure indicators mass concentration, particle number concentration, and surface area are discussed. By applying colloid chemistry kinetic equations describing particle agglomeration and sedimentation for the case of titanium dioxide nanoparticles, a limited exposure assessment including some of the factors mentioned is conducted with particle number concentration as the exposure indicator. The results of the modeling indicate that sedimentation, shear flows, and settling are of less importance with regard to particle number based predicted environmental concentrations. The inflow of nanoparticles to the water compartment had a significant impact in the model, and the collision efficiency (which is affected by natural organic matter) was shown to greatly affect model output. Implications for exposure modeling, regulation, and science are discussed. A broad spectrum of scientific disciplines must be engaged in the development of exposure models where nano-level properties are linked to macro-scale risk. [ABSTRACT FROM AUTHOR]

Dislocation-solute interactions are ubiquitous in solids, yet their dual nature in strengthening or softening the material is not well understood. Results of a novel concurrent multiscale approach reveal that the local environment of W solutes in Ta has a dramatic effect both on the dislocation mobility and slip paths. W solutes can enhance or reduce the mobility, and may result in spontaneous dislocation glide. The atomistic mechanism responsible for the dual nature of solutes is elucidated. [ABSTRACT FROM AUTHOR]

Bruce King joined Gordon Stone's research group at Harvard University in 1957 and initiated his research on synthetic transition metal organometallic chemistry. The work that he presented at the Stone Symposium evolved during more than a half-century from his 1959 discovery of the sandwich compound (η5-C5H5)V(η7-C7H7) while a student in Gordon Stone's Harvard laboratory. After leaving Gordon's research group Bruce King continued synthetic studies on cycloheptatrienylmetal compounds. This led to the discovery of the first trihapto derivatives (η5-C5H5)Mo(CO)2(η3-C7H7) and (η3-C7H7)Co(CO)3, while working at the Mellon Institute (now Carnegie-Mellon University) in the 1960s. Bruce King then continued work in synthetic inorganic and organometallic chemistry and related experimental work at the University of Georgia until the late 1990s, when he closed down his experimental ('wet chemistry') laboratory to concentrate on theoretical and mathematical chemistry. At that time he initiated collaborative work in various areas of computational inorganic and organometallic chemistry, including density functional theory studies of cycloheptatrienylmetal derivatives related to some of his early synthetic successes noted above. Bruce King's work in computational inorganic chemistry evolved and expanded greatly in collaboration with groups at several Chinese universities and he now holds several adjunct academic appointments in China. The computational part of the research presented here is in collaboration with Prof. Hongyan Wang at Southwest Jiaotong University in Chengdu, China, and Prof. Xuejin Feng at Jiangnan University in Wuxi, China. [ABSTRACT FROM AUTHOR]

Anthony Hill joined Gordon Stone's research group as a post-doctoral research assistant from 1986-8 in the halcyon days of the 'E317' lab at the University of Bristol. The supportive environment of creative and imaginative synthetic design that Gordon fostered in Bristol was unparalleled, quite without apology for the pursuit of curiosity-driven science that bordered on molecular fine arts. In 1996 Gordon handed over the reins of Advances in Organometallic Chemistry, the journal series, now running to some 60 volumes, which Gordon inaugurated in 1964 with Bob West. During Gordon's mid-career phase, when he had a mere 400 publications to his name, carbyne chemistry held special interest for him. The work to follow reflects the enthusiasm those times engendered in this intriguing class of compounds. [ABSTRACT FROM AUTHOR]

In this section graphical abstracts on chemistry studies are presented, including "Oxidation of Hydrobenzoins to Benzils by Ammonium Chlorochromate/Montmorillonite K-10 Under Ultrasound Irradiation," "Highly Efficient Synthesis of 14-Aryl-14H-Dibenzo[A,J]Xanthenes Catalyzed by Carbon-Based Solid Acid Under Solvent-Free Conditions" and "Microwave-Assisted Simple Synthesis of Substituted 4-Quinolone Derivatives."

A simple and convenient method for the synthesis of N-hydroxysuccinimide ester is developed using triphosgene as an acid activator. Several aromatic and aliphatic N-hydroxysuccinimide esters are prepared from their corresponding carboxylic acids at room temperature in good yields in a rapid process using triphosgene. Some of the major advantages are mild conditions, good yields, and easy operation. [ABSTRACT FROM AUTHOR]