bluuebunny/crossref_metadata_2025 huggingface dataset:
TiO2/rGO/CuS Nanocomposites for Efficient Photocatalytic Degradation of Rhodamine‐B Dye
Authors: Gunnagol Raghu M. , Rabinal Mohammad Hussain K.
Published: May 2019

In this work, a simple two step synthesis of Titanium dioxide / Reduced graphene oxide / Copper sulfide (TiO2/rGO/CuS) and its improved photocatalytic activity is reported. TiO2/rGO is prepared by electrochemical anodization of Ti metal in NaCl‐graphene oxide solution as an electrolyte. Later CuS is incorporated to TiO2/rGO to form the composite TiO2/rGO/CuS by chemical precipitation at room temperature. The optical properties, phase and morphology of the material is characterized by UV‐visible spectroscopy, X‐ ray diffraction, field emission scanning electron microscopy, high resolution transmission electron microscopy and X‐ray photoelectron spectroscopy. The photocatalytic activity is tested by the degradation of hazardous Rhodamine‐B dye under ultraviolet and visible light exposures. An enhancement of photocatalytic activity is observed in TiO2/rGO/CuS as compared to pure TiO2 or TiO2/rGO nanocomposites. The enhancement is mainly due to wide range of optical absorption of CuS and the interfaced rGO, which facilitates the efficient charge separation and charge transport. The present material exhibits superior stability that is tested by its recycling photocatalytic activity.
Embedding Pt‐SnO Nanoparticles into MIL‐101(Cr) Pores: Hydrogen Production with Low Carbon Monoxide Content from a New Methanol Steam Reforming Catalyst
Authors: Kamyar Niloofar , Khani Yasin , Amini Mostafa M. , Bahadoran Farzad , Safari Nasser
Published: May 2019

The catalyst Pt‐SnO@MIL‐101(Cr) was prepared using the cis‐PtCl(SMe2)2(SnCl3) complex as a single precursor and characterized by inductively coupled plasma optical emission spectroscopy, (ICP‐OES), X‐ray powder diffraction (XRD), BET surface area analysis (SBET), X‐ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), field‐emission scanning electron microscopy (FE‐SEM), and temperature program reduction (TPR). A new complex, cis‐PtCl(SMe2)2(SnCl3), was synthesized from the reaction of PtCl2(SMe2)2 with SnCl2 and characterized by thermogravimetric analysis (TGA), ICP‐OES, and 1H NMR spectroscopy and used as the source of metals for preparation of the catalysts. The fabricated catalyst, Pt‐SnO@MIL‐101(Cr), with 10.2%, 19.7%, and 28.9% platinum loadings were used in a steam reforming of methanol (MSR) reaction using a microstructure monolith reactor in the temperature range of 150–300 °C. A high methanol conversion with a good selectivity of H2 and low CO selectivity was achieved in light of the stability of the catalyst with a small amount of coke formation in the monolith system.
A Collaboration of Surface Protection and Bulk Doping for High‐performance Li‐rich Cathode Materials
Authors: Wang Min‐Jun , Yu Fu‐Da , Sun Gang , Gu Da‐Ming , Wang Zhen‐Bo
Published: May 2019

Li‐rich layered oxides (LLRO) are promising high energy‐density cathode, but always suffer from the oxygen loss in initial activation and gradual structure transformation during cycling, which leads to capacity degradation and potential decay. Here, we employ a simple strategy to achieve the collaboration of surface protection and bulk doping for improving the performance of Li‐rich material. Scanning electron microscope and transmission electron microscopy tests demonstrate that a nanoscale protective layer of magnesium pyrophosphate is uniformly coated on the Li‐rich material surface. X‐ray diffraction test indicates Mg2+ and P2O74− are incorporated into the crystal structure, which induces the larger lattice spacing and lower cation mixing. As a result, the resultant LLRO displays extremely high Coulombic efficiency of 91.8% and discharge capacity of 288.4 mAh g−1, showing prominent cycling stability of 89.2% after 200 cycles. Furthermore, our strategy also suppresses the attenuation of average voltage during cycling and the potential drop is only 0.56 mV per cycle from 25 th to 200 th cycle. The excellent electrochemical performance can be ascribed to the combined merits of surface protection and bulk doping. This strategy may provide some new insights into the design and synthesis of high‐performance electrode materials.
Synthesis of N,N‐Disubstituted Thiocarbamates from Thiocarbamoyl Fluorides with Alcohols/Phenols/Thiophenols/Thioalcohols Through Copper Catalysis
Authors: Yang Jun , Zhen Long , Jiang Liqin
Published: May 2019

Traditional methods for preparing N,N‐disubstituted thiocarbamates require highly toxic, flammable and volatile reagents, or their derivatives. Recently, we developed a general method for thiocarbamoyl fluorides from safe, cheap, and easily available starting materials. Reported reactions involving thioyl fluoride with nucleophiles are very scarce. In this report, copper catalyzed reaction of thiocarbamoyl fluorides with phenols/thiophenols/alcohols/thioalcohols under Na2CO3 at 50 °C or at 80 °C in CH3CN were first developed, affording the corresponding N,N‐disubstituted thiocarbamates in moderate to excellent yields. When alcohols are cheap and their boiling points are less than 120 °C or they are water‐soluble, CuCl catalyzed reaction of thiocarbamoyl fluorides with alcohols at 50 °C was also developed. The reaction has good functional group tolerance. Methoxy, methyl, chloro, bromo, nitro, even ester functional groups were all tolerated. Control reactions demonstrated that copper catalyst played the key role on the success of these novel reactions.
Deep Eutectic Solvent Mediated Alkyne‐Carbonyl Metathesis (ACM) Reaction for the Synthesis of 2H‐Chromene Derivatives
Authors: Annes Sesuraj Babiola , Vigneshwar Kulandaiappan , Nivedha Kolanchinathan , Manojveer Seetharaman , Ramesh Subburethinam
Published: May 2019

2H‐Chromene is an important structural motif present in many biologically active compounds, natural products and showed many other properties. Deep Eutectic Solvent (DES) an environmentally benign and alternative to the conventional organic volatile solvents has been utilized first time for the synthesis of the 2H‐chromene derivatives in moderated to excellent yields. The DES is recycled for 5 times for the synthesis of 2H‐chromene derivatives. Based on the stability of ring size, we justified the regio‐selectivity on the formation of cyclization product. Based on the control experiments, we ruled out the free radical mechanism and propose the ACM mechanistic path to construct chromene skeleton.
Simple and Controllable Synthesis of Three‐Dimensional Spheroidal Structure of MoS2/rGO under Lower Temperature for Enhanced Properties in Lithium Battery
Authors: Yang Zezhou , Yang Jingjing , Zong Liming , Ren Lan , Guli Mina
Published: May 2019

MoS2 has a larger specific capacity than graphene, however with low conductivity and easily broken structure during charging and discharging. Graphene can be used as a carrier to prevent agglomeration of MoS2 sheet, so that the electrolyte is sufficiently in contact with the active material. MoS2/rGO is prepared by hydrothermal method in simple, fast and controllable way, which is low in energy consumption and excellent in sample quality. Materials are characterized by SEM, XRD and electrochemical performance tests. Then, they are used as the anode materials of the lithium half‐cell and the performance of the lithium half‐cell is tested and analyzed. MoS2 has a capacity of 608.4 mAh g−1, which is higher than the existing lithium battery anode material. MoS2/rGO has a unique three‐dimensional spheroidal structure. The conductivity and structural stability of the material are greatly improved, moreover, the capacity is further improved to 853.7 mAh g−1.
Fe3O4 Nanoparticles Supported on Arc‐synthesized Carbon Nanotubes as Advanced Electrocatalyst for Oxygen Reduction Reaction
Authors: Zhao Jiang , Luo Jinsong , Li Dan , Zhou Ziwei , Ji Guanghan , Shi Qingling , Xiang Yangjun
Published: May 2019

Oxygen reduction reaction (ORR) is an important half reaction in many renewable energy conversion and storage sources. The development of efficient, cost‐effective and durable non‐precious ORR catalysts with their catalytic efficiencies close to expensive Pt‐based catalysts is promising towards large‐scale practical applications of fuel cells and metal‐air batteries. Herein, we report a facile and scalable in‐situ synthesis of Fe3O4 nanoparticles supported on carbon nanotubes hybrid material using arc‐discharge method in low‐pressure air and use Fe3O4/CNTs hybrid as a highly efficient ORR electrocatalyst. The as‐synthesized Fe3O4/CNTs catalyst shows excellent ORR catalytic activity with its performance close to or even better than the commercial 20wt% Pt/C in alkaline media due to the synergistic effect between Fe3O4 and CNTs. This study provides a new insight into non‐precious metal ORR catalysts that are feasible in alkaline membrane fuel cells and metal‐air batteries.
Synthesis and Biological Evaluation of New Isatin‐Based QACs with High Antimicrobial Potency
Authors: Bogdanov Andrei V. , Zaripova Ilyuza F. , Voloshina Alexandra D. , Sapunova Anastasia S. , Kulik Natalia V. , Bukharov Sergey V. , Voronina Julia K. , Vandyukov Alexander E. , Mironov Vladimir F.
Published: May 2019

A simple and easy condensation reaction of aryl‐ or N‐substituted isatins with Girard's reagents P and T was found to be useful in obtaining of water‐soluble isatin‐based quaternary ammonium compounds (QACs) bearing pyridinium or trimethylammonium moiety with high yields. Their antimicrobial activity was evaluated. Selective activity against Gram‐positive bacteria (S. aureus 209p and B. cereus 8035) and yeast‐like fungus Candida albicans 855–653 was shown. The influence of the substituent's nature as in the aromatic fragment as at position 1 on the activity was established. The most active are the pyridinium salts containing sterically hindered phenolic fragment at the position 1 of the heterocycle. The structures of all novel compounds were fully characterized using IR and NMR spectroscopies as well as XRD analysis.
An Intrinsically Conductive Phosphorus‐Doped Perovskite Oxide as a New Cathode for High‐Performance Dye‐Sensitized Solar Cells by Providing Internal Conducting Pathways
Authors: Xu Meigui , Wang Wei , Liu Yu , Zhong Yijun , Xu Xiaomin , Sun Yuankang , Wang Jun , Zhou Wei , Shao Zongping
Published: May 2019

State‐of‐the‐art dye‐sensitized solar cells (DSSCs) usually use the noble and scarce platinum (Pt) cathode, which strongly limits the practical applications of DSSCs. Accordingly, low‐cost, highly active, and stable alternatives to Pt are highly desired. Herein, an intrinsically conductive perovskite oxide is reported as a new cathode for DSSCs using a simple nonmetal element doping strategy. The phosphorus‐doped perovskite oxide (SrCo0.95P0.05O3−δ [SCP]) shows superior activity/durability for the triiodide (I3−) reduction reaction (IRR) and structural stability relative to the parent compound (SrCoO3−δ [SC]) due to the greatly enhanced electrical conductivity and the stabilization of the perovskite structure. The internal conducting pathways are demonstrated to be very important to obtain high IRR activity of the perovskite cathode, even when the cathode is incorporated with conductive multiwalled carbon nanotubes (MWCNTs). The DSSC with the N719 dye and SCP/MWCNTs cathode displays a superior power conversion efficiency (PCE) of 10.1% to those with Pt (8.11%) and SC/MWCNTs (6.80%) cathodes. In addition, the DSSC with the C101 dye and SCP/MWCNTs cathode shows an attractive PCE of 12.2% with an enhancement of 23%, as compared with the Pt cathode, suggesting that the SCP/MWCNTs composite can be one of the best substitutions to the Pt cathode, which can benefit the future industrialization of DSSCs.
Hot Temperature Mechanical Behavior of High‐Permeability 6.5 wt% Si Electrical Steel in a Mushy Zone
Authors: Hu Wenli , Zhang Yuanxiang , Yuan Guo , Zhang Xiaoming , Wang Guodong
Published: May 2019

Twin‐roll strip casting (TRSC) technology is successfully applied to obtain 6.5 wt% Si electrical steel (6.5 wt% Si steel) in a laboratory platform, although there are problems in the strip surface quality control restricting further industrial applications of the TRSC. Hot temperature mechanical behavior in the mushy zone associated with the cracking susceptibility of 6.5 wt% Si steel is studied using the Gleeble‐3800 simulation system in the temperature range of 1350–1435 °C and a strain rate of 3 s−1. The characteristic temperatures including zero strength temperature (ZST) and zero ductility temperature (ZDT) are qualitatively determined, and the hot brittle temperature range in the mushy zone is further confirmed. Results indicate the tensile strength and ductility both increase with decreasing tensile temperature once the solidus fraction reaches a critical value. The ZST and ZDT in the mushy zone are determined to be ≈1427 and ≈1390 °C, respectively, and the hot brittle temperature range is 1390–1427 °C. The critical strain for internal crack generation in the hot brittle temperature range is estimated to be ≈0.24% on the basis of an empirical model developed by Y. M. Won. To reduce the cracking susceptibility of studied 6.5 wt% Si steel under TRSC, a rolling process is prohibited in the temperature range of 1390–1427 °C.
Conclusion: The Need to Develop the Code of the Street into a General Approach
Authors: Heitmeyer Wilhelm , Kurtenbach Sebastian , Zdun Steffen
Published: May 2019

The final results of the study are interpreted in this concluding chapter and the research question is answered. The study shows that the code of the street theory has to be modified to explain youth violence in different cultural contexts, but does have general elements. Furthermore, street codes are shaped by micro-driven issues, like the personality of juveniles, as well as macro-factors, like the entire society. Also, street codes have to be placed into the broader picture of street culture, to understand spatial-related differences.
Violence-Related Norms and the “Code of the Street”
Authors: Kurtenbach Sebastian , Rauf Abdul
Published: May 2019

This chapter is a survey of the status quo of research on the code of the street since the publication of Anderson’s work (1999). Prioritizing the elements of the street code, we critically discuss various empirical studies on the street code. It covers the development of the code of the street: family types, street socialization, street knowledge, manhood, and violence. Scrutinizing the relevant empirical research both in their geographical spaces and different disciplines gave us the confidence to use the code of the street as a theoretical framework for our study.
Comparing Violence-Related Norms
Authors: Howell Simon , Zdun Steffen
Published: May 2019

The goal of this empirical study is a comparison of violence-related norms. Although the code of the street is our particular concern in this study, violence-related norms remain the general concern. This chapter aims to provide a selective literature review on both these issue, with a particular emphasis on the situation in the three countries comprising this study. Moreover, the chapter reflects on the need for comparison, methodological issues of cross-cultural comparison, as well as the functionality of conducting a comparison.
Research Design
Authors: Kurtenbach Sebastian , Zaman Muhammad
Published: May 2019

This chapter deals with the research design and protocols of the research. It outlines the universe (a comparison of Germany, Pakistan and South Africa), the unit of analysis (juveniles 16–21), the tools (interview guidelines), and techniques of the data collection process (in-depth interviews). This chapter also documents the tools and techniques of the data analysis (MAXQDA 18). It also sets out the sample size (30 interviews from each country) and the ten expert interviews conducted in each country. Finally, the analytical outline of the code of the street is presented.
Description of the German Context
Authors: Kurtenbach Sebastian
Published: May 2019

In this chapter, the German research context is described in detail by way of a thorough depiction of the three research sites, being Dortmund-Nordstadt, Duisburg-Marxloh, Berlin-Wedding, and Berlin-Neukoelln. Here too, the sample of the interviews of the male juveniles and the frequencies of the codings are presented. The chapter contributes to a better understanding of the German sample of our study.
Description of the South African Context
Authors: Howell Simon
Published: May 2019

In this chapter, a description of the sample and the sites of research pertaining to the South African sample is provided. The chapter also details the unique structural and historical parameters that have shaped South African neighborhoods, the country, and indeed the people. Two sites in the country were sampled, and these are drawn upon in contrasting the very different lives of people who live in South Africa contemporarily. With this in place, some initial thoughts are advanced, detailing the relationship between structure, personhood, and norms.
Water alternating gas incremental recovery factor prediction and WAG pilot lessons learned
Authors: Belazreg Lazreg , Mahmood Syed Mohammad
Published: May 2019

Water alternating gas (WAG) injection process is a proven enhanced oil recovery (EOR) technology with many successful field applications around the world. WAG pilot projects demonstrate that WAG incremental recovery factor typically ranges from 5 to 10% of original oil in place, though up to 20% has been observed in some fields. Despite its proven success, WAG application growth has been very slow. One of the reasons is the unavailability of robust analytical predictive tools that could estimate WAG incremental recovery factor, which is required for preliminary economic analysis before committing to expensive and time-consuming detailed technical studies and field pilot test that often requires a lot of input data. A semi-numerical model for WAG incremental recovery factor prediction was developed based on data mining of published WAG pilots to fill this gap. An extensive review of published WAG pilot projects was carried out, and consequently, 33 projects from 28 fields around the world were selected for this research study. Field WAG incremental recovery factor and parameters with total of one hundred and seventy-seven (177) observations were inputted to the predictive model. A predictive model was developed using both regression and group method of data handling (GMDH) techniques; 70% of the 33 WAG pilot projects data were used as validation, whereas remaining 30% of data set were used for validation. The predictive model results achieved with coefficient of determination (R2) from the regression method were ranging from 0.892 to 0.946 and 0.854 to 0.917 for training and validation sets, respectively. However, the prediction model coefficient of determination (R2) using GMDH method was ranging from 0.964 to 0.981 and 0.934 to 0.974 for training and validation, respectively. The developed predictive model can predict WAG incremental recovery factor versus multiple input parameters that include rock type, WAG process type, hydrocarbon pore volume of injected gas, reservoir permeability, oil gravity, oil viscosity, reservoir pressure, and reservoir temperature. The results of the study demonstrated that few input parameters have a significant impact on WAG incremental recovery factor as reservoir permeability and hydrocarbon pore volume of injected gas. This research study uses a novel approach in pre-defining the expected incremental WAG recovery factor before committing resources for building complex numerical reservoir simulation models and running WAG pilot tests, which are very time-consuming and costly and require extensive data input.
A General Age-Specific Mortality Model With an Example Indexed by Child Mortality or Both Child and Adult Mortality
Authors: Clark Samuel J.
Published: May 2019

The majority of countries in Africa and nearly one-third of all countries require mortality models to infer the complete age schedules of mortality that are required to conduct population estimates, projections/forecasts, and other tasks in demography and epidemiology. Models that relate child mortality to mortality at other ages are important because almost all countries have measures of child mortality. A general, parameterizable component model (SVD-Comp) of mortality is defined using the singular value decomposition and calibrated to the relationship between child or child/adult mortality and mortality at other ages in the observed mortality schedules of the Human Mortality Database. Cross-validation is used to validate the model, and the predictive performance of the model is compared with that of the log-quadratic (Log-Quad) model, which is designed to do the same thing. Prediction and cross-validation tests indicate that the child mortality–calibrated SVD-Comp is able to accurately represent the observed mortality schedules in the Human Mortality Database, is robust to the selection of mortality schedules used for calibration, and performs better than the Log-Quad model. The child mortality–calibrated SVD-Comp can be used where and when child mortality is available but mortality at other ages is unknown.
Do Campaign Contributions from Farmers Influence Agricultural Policy? Evidence from a 2008 Farm Bill Amendment Vote to Curtail Cotton Subsidies
Authors: Callahan Scott
Published: May 2019

This article studies the political activities of individual cotton farmers and cotton political action committees (PACs) by exploiting a vote to amend the 2008 Farm Bill. Using a simultaneous model, I estimate reduced form equations for donations from cotton farmers and cotton PACs using tobit models, which instrument donations in the probit vote equation to control for the hypothesized endogeneity between campaign contributions and legislative votes. I find evidence that cotton farmers, like cotton PACs, contribute to legislators representing a median cotton farming constituency. I find no evidence that contributions from cotton farmers or cotton PACs significantly affected the vote decision.
Duration ≠ Seriousness of Commitment: An Empirical and Theoretical Critique of Nyarko's Treaties vs. Executive Agreements
Authors: Koremenos Barbara
Published: May 2019

In “Giving the Treaty a Purpose,” Julian Nyarko distinguishes between treaties and executive agreements and argues that treaties signal a higher level of commitment to our partners in cooperation than do executive agreements because treaties are more durable. Nyarko uses survival-time analysis to demonstrate that treaties last longer than executive agreements—that is, treaties are less likely to drop out of the Treaties in Force (TIF) series in any given year. The longer life of treaties is Nyarko's proxy for their greater durability. Nyarko argues that his result holds “even after controlling for a number of covariates that could influence the durability of the agreement,” like particular presidents, subject areas, and partner countries as well as the degree of divided government. Nonetheless, Nyarko's list omits the most important variable affecting durability as he defines it: intended duration. Sometimes the intended duration of a piece of formal international law is finite. Indeed, as I will explain in this response, under certain (and common) conditions, this choice of a finite duration is what makes the commitment credible (or, in Nyarko's language, reliable).
Senate Treatment of Select International Agreements, 2013–2018
Authors: Taylor Margaret L.
Published: May 2019

When I finished reading Julian Nyarko's “Giving the Treaty a Purpose: Comparing the Durability of Treaties and Executive Agreements,” I found my mind wandering through memories of the more than five years I spent working on Capitol Hill as Counsel for the Senate Foreign Relations Committee (SFRC)—a role that often required me to figure out how best to preserve the constitutional prerogatives of Congress in the face of the various types of international agreements the executive branch produced. This essay recounts my impressions of how the Senate handled different agreements in the 2013–2018 timeframe—Article II treaties, the Paris Climate Agreement, and the Iran Nuclear Agreement. Unlike Professor Nyarko's ambitious and impressive work to categorize and statistically analyze the durability of Article II treaties and executive agreements—which I applaud and find useful—this essay is modest in purpose. I contend that how Congress handles different types of agreements is largely a product of specific political dynamics—including political ownership, policy entrepreneurism, and electoral risk—that can be unpredictable. Because of these dynamics, the differences that Nyarko reveals regarding the durability of Article II treaties and executive agreements are unlikely to produce a significant change in official practice.
Colonial Intrusion and Stages of Colonialism in Chinua Achebe’sThings Fall Apart
Authors: Mengara Daniel M.
Published: May 2019

Chinua Achebe’s first novel,Things Fall Apart, has continued to offer—perhaps much more than his third novel,Arrow of God—the most vivid account of the process of early colonial penetration in Africa. This study examinesThings Fall Apartthrough an analytical and conceptual framework that illuminates the five stages of colonialism in Africa. These five stages (exploration, expropriation, appropriation, exploitation, and justification) were necessary in order for colonialism to become both aneffectivetoolfordomination and asuccessfultoolofdomination; as such, they provide powerful glimpses into Achebe’s fictional representation of the cataclysm embodied by colonial intrusion, not only within the confines of the fictional Igbo universe that he depicts, but also throughout a sub-Saharan African world whose cultural and sociopolitical ethos were shaken to their core. An analysis of these stages, therefore, leads to an understanding of colonialism that defines it not as a series of specific historical events, spaces, and places, but rather as aprocessor aseries of psycho-historical processeswith a certain number of inescapable features that conspired to make it an effective tool of and forsustainedpolitical, cultural, and economic domination in sub-Saharan Africa. Achebe’s novel can be used as a tool that can help to decipher and foreground thepsycho-historical processesinherent in what, ultimately, may be called “the psychology of colonialism.”
Measuring access to primary healthcare services after stroke: A spatial analytic approach
Authors: Finch Emma , Liu Yan , Foster Michele , Cruwys Tegan , Fleming Jennifer , Worrall Linda , Williams Ian , Shah Darshan , Aitken Philip , Corcoran Jonathan
Published: May 2019

Objective:

To determine accessibility of the primary healthcare system for patients with stroke recently discharged from hospital.

Methods:

This project mapped retrospective patient location data and the location of primary healthcare services in the same region. Patient location data were from all patients with stroke (N = 1595: January 2011–January 2017) discharged from one metropolitan hospital to the local Primary Health Network. Geographic Information System technology was used to map the patient discharge locations and the spatial distribution of primary healthcare services (general practitioner, pharmacy, allied health) across the region. Road network data were used to measure the level of access from each patient’s discharge location to the services.

Results:

Access to primary healthcare services was variable. Areas with larger proportions of patients with stroke did not necessarily have good service access. With an increase in travel time, the number of services accessible to patients also increased. However, the spatial variation of access to services remained largely unchanged.

Conclusion:

Access to primary healthcare services for patients with stroke varies spatially, with a trend towards relatively low levels of accessibility for many patients. There is an urgent need for future planning to consider geographical access to primary healthcare services for patients with stroke.
Turbomachinery Waves
Authors: Horlock J H , Daneshyar H
Published: May 2019

Two methods of analysis are developed for the unsteady wave flow through axial turbomachinery of high hub-tip ratio. In the first method, the machine is supposed to consist of an infinite number of small stages. Differential equations for the instantaneous values of flow properties are derived which may be solved directly or by the method of characteristics. Conditions for wave propagation are discussed. Secondly, a model is used in which actuator discs replace the stages and the flow is axial between the stages. This is a good approximation in many compressors in which the leaving angle from the stators is small. Again the method of characteristics may then be used for solving the equations of unsteady flow between the discs.
Matthew Williams Stirling, 1896-1975
Authors: Coe Michael D.
Published: May 2019

With the death on January 23, 1975, of Matthew W. Stirling, pioneer archaeologist, ethnolo-gist, and the discoverer of the Olmec civilization, American archaeology has lost one of its grand men. He is survived by his wife, Marion, a son, Matthew, his daughter Ariana, and one grandchild.

Matt was born in Salinas, California, on August 28, 1896. His father was manager for the Southern Pacific Milling Co. and was in charge of establishing warehouses in the Salinas Valley, so he lived in various small towns while growing up. While a boy and young man, he also spent considerable time on the ranches of his grandfather Williams (for whom he was named) near Gonzalez and Salinas, in a milieu that has provided the setting for some of the novels of John Steinbeck, an old family friend who often discussed the pioneer days with Matt’s maiden aunts, Did and Bee.
What Happened to the United Nations Ministate Problem
Authors: Gunter Michael M.
Published: May 2019

During the past decade, a number of scholarly analyses of the United Nations ministate problem have appeared. This concern is understandable because the dilemma of ministate representation goes to the heart of the malaise increasingly gripping the world organization: How to square formal voting power with the realities of international politics? Indeed, no less of an authority than the late Secretary-General U Thant, in his final Annual Report, warned his reluctant audience that the ministate problem “is likely to become more acute in the years to come.”
The Kiev and the Turkish Straits
Authors: Knight H. Gary
Published: May 2019

On July 18, 1976, the Soviet naval vessel, Kiev, transited the Turkish Straits from the Black Sea to the Mediterranean, with Turkish consent. Questions have been raised concerning the international legality of this transit, and in light of earlier reaction to an alleged violation by the Soviet Union of the rules on the passage of submarines through the Turkish Straits it seems appropriate to examine the facts and the governing law.
Amino acid metabolism in the piglet: 2. Influence of fasting on plasma free amino acid concentration and in vivo oxidation of methionine, isoleucine and threonine
Authors: Chavez E. R. , Bayley H. S.
Published: May 2019

1. The influence of a 24 h fast on the concentrations of free amino acids in the plasma, and upon the oxidation rates of methionine, isoleucine and threonine was studied (using early weaned, 4-week-old piglets which were receiving a semi-purified diet.

2. There was no change in the total concentration of the essential amino acids as a result of the 24 h fast: the concentration of the branched-chain amino acids increased, but the effect of this was offset by decreases in the concentrations of arginine, histidine, lysine, methionine and phenylalanine. There was a reduction in the concentration of the non-essential amino acids.

3. The piglets received infusions of L-[1-14C]methionine, L-[U-14C]isoleucine and L-[U-14C]threonine, and the recovery of the label in carbon dioxide was determined. Less than 5% of the activity from methionine was recovered in the CO2 from the fed piglets, whereas 12% was recovered from the fasted piglets. The corresponding values with threonine were 11 and 19% but there was no effect of fasting on the recovery of the label from isoleucine in CO2.

4. The initial dilution of a single dose of a labelled amino acid infused into the bloodstream depends on the plasma concentration of the amino acid. Nutritional regimens may effect the free amino acid concentration in the plasma. Thus comparisons based upon direct determination of activity recovered in CO2 from the labelled dose of an amino acid with animals on different nutritional regimens could be misleading, unless the differences in the concentrations of the amino acid in the plasma are considered.
Nitrogen metabolism in calves: Effect of giving different amounts of dietary casein with and without formaldehyde treatment
Authors: Williams A. P. , Smith R. H.
Published: May 2019

1. Calves were given a basal diet of straw and flaked maize (12 g nitrogen/kg dry matter (DM)) or diets with some flaked maize replaced by untreated (UT) casein or formaldehyde-treated (FT) casein to give 19, 26 or 34 g N/kg DM.

2. At all intakes rumen ammonia concentrations were lower and amounts of total-N, non-ammonia-N and amino acid-N entering the duodenum were higher when FT-rather than UT-casein supplements were given.

3. Direct measurement of casein entering the duodenum indicated that giving FT rather than UT casein led to much greater amounts of dietary casein escaping degradation in the rumen (70–90% compared to 10–20%). Calculated values for fermentable N indicated that with this low degradability diets containing FT-casein would have provided inadequate N for maximum microbial synthesis in the rumen, and this probably accounted for the marked reduction in amounts of non-casein-N entering the duodenum when FT rather than UT casein was given.

4. Amino acid patterns in duodenal digesta samples after giving the basal diet or diets containing UT-casein were similar. Giving diets containing FT-casein led to changes in this pattern which could sometimes, although not always, be accounted for by estimated differences in proportions of dietary and microbial proteins.

5. At the highest level of N intake FT-casein-supplemented diets led to significantly higher concentrations of most essential amino acids and lower concentrations of most non-essential amino acids in plasma than did UT-casein-supplemented diets. Plasma urea concentrations increased with increasing N intake but were not significantly different for UT- and FT-casein-supplemented diets.
The relative effects of a low-protein-high-carbohydrate diet on the free amino acid composition of liver and muscle
Authors: Lunn P. G. , Whitehead R. G. , Baker B. A.
Published: May 2019

1. Free amino acid concentrations in the plasma have been compared with those in liver and quadriceps muscle, in rats fed on diets containing 209 (control) and 31 (low-protein) g protein/kg. The effects of the low-protein diet on diurnal variations in these values were also measured.

2. In the plasma, the total amino acid concentration was significantly lower in animals given the low-protein diet, at all times of day except 12.00 hours. In the liver, and to a lesser extent the muscle, total amino acid concentration was maintained.

3. In the control animals, diurnal variation in the concentrations of both essential and non-essential amino acids was very similar in plasma, liver and muscle. In animals given the low-protein diet, although the same diurnal pattern was maintained for non-essential amino acids, that occurring among the essential amino acids had virtually disappeared.

4. In plasma, the mean 24 h concentration of essential amino acids decreased from 24· mmol/l in control animals to only 1·29 mmol/l in the low-protein-fed animals. Concentrations in muscle and liver were reduced by a similar proportion (from 8·6 to 5·56 μmol/g and from 8·67 to 5·05 μmol/g respectively). Conversely the concentrations of non-essential amino acids in animals given the low-protein diet were increased in plasma (from 1·53 to 2·00 mmol/l), muscle (from 12·5 to 14·3 μmol/g), and liver (from 16·8 to 20·5 μmol/g), muscle showing the lowest increase.

5. With the exceptions of lysine, threonine, cystine and tyrosine, the concentrations of all other essential amino acids were reduced more in liver than in muscle. The relationship between this and the failure to maintain plasma albumin concentrations is discussed.
The effect of cold exposure of sheep on digestion, rumen turnover time and efficiency of microbial synthesis
Authors: Kennedy P. M. , Christopherson R. J. , Milligan L. P.
Published: May 2019

1. Six closely shorn sheep were given brome grass (Bromus inermis) pellets at 1 h intervals and maintained at ambient temperatures of −1 to 1° and 18–21° for 28 d. Measurements of digestion were made during the last 10 d of temperature exposure.

2. Cold exposure resulted in a reduction in apparent dry matter (DM) digestibility from 0·482 to 0·450, and of apparent digestibility of organic matter (OM) from 0·511 to 0·477. Neither apparent digestibility nor retention of nitrogen was affected.

3. Apparent digestibility of OM in the rumen decreased from 0·300 to 0·242 with cold exposure, and was highly correlated with turnover time in the rumen of 108Ru, which was used as a particulate marker.

4. The efficiency of microbial synthesis (g N incorporated into microbial cells/kg OM apparently digested) was correlated with the dilution rate of the solute marker (51Cr) and with the turnover time of the particulate marker (103Ru) in the rumen.

5. Digestion in the intestine of DM and OM accounted for significantly more of apparent digestion in the whole gastrointestinal tract for sheep kept in the cold than for sheep kept in the warm. The apparent digestibilities of DM and OM entering the intestines were similar in sheep on both treatments, but significantly more non-ammonia-N was digested in the intestines of cold-exposed sheep.

6. The influence of dilution rate of rumen fluid on the efficiency of synthesis of microbial cells in the rumen is discussed.
The histological effects of copper and zinc on chick embryo skeletal tissues in organ culture
Authors: Rest Joan R.
Published: May 2019

1. The effects of copper and zinc on organ cultures of chick embryo cartilage and bone maintained in low-trace-metal, chemically defined media for up to 8 d were studied macro-scopically, histologically and histochemically. Length and wet-weight measurement of explants were assessed statistically.

2. No effects were found with Cu concentrations of 0·5–1·5μg/ml medium. Between concentrations of 5 and 40μg Cu/ml medium, lengths and wet-weights of cartilage cultures decreased significantly (P< 0·001) compared with controls. The decrease was directly proportional to increasing Cu concentration, and that of the length was greater with increasing period of culture (P< 0·001).

3. With 5–20μg Cu/ml medium cartilage and bone became yellow in colour, and chondrocytes were swollen, rounded and basophilic. They were detached from their lacunae and the quantity of matrix was reduced. Loss of alkaline phosphatase (EC3.1.3.1) activity and disappearance of glycogen accompanied the degeneration. Osteogenesis ceased, cells failed to divide and mature, lost their enzymes and died. Cu did not accumulate in the bone matrix.

4. The direct toxic effects of Cu for cartilage and bone may underlie some of the skeletal changes in hepatolenticular degeneration (Wilson’s disease).

5. As Zn concentrations were increased from 2·5 to 7·5μg/ml medium, lengths and wet-weights of cartilaginous cultures were significantly increased (P< 0·001). As Zn concentrations were further increased (from 10 to 40μg/ml medium), lengths and wet-weights were significantly decreased (P< 0·001).

6. Zn stimulated chondrocyte division and vacuolation of cytoplasm. With higher Zn concentrations toxic changes of granular basophilia, lacunar detachment and necrosis were seen. Differentiation and functioning of osteoblasts, osteoclasts and chondroclasts were stimulated by Zn.

7. Zn was found in bone matrix, osteoblasts, osteocytes and hypertrophied chondrocytes.
Serum albumin and transferrin in protein-energy malnutrition: Their use in the assessment of marginal undernutrition and the prognosis of severe undernutrition
Authors: Reeds P. J. , Laditan A. A. O.
Published: May 2019

1. Deficits in weight- and length-for-age, and serum albumin and transferrin concentrations were determined for children who were either marginally undernourished (twenty-five children) or suffering from either marasmus (thirty-two children) or kwashiorkor (twenty-six children) defined according to the Wellcome Classification (Waterlow, 1972). The measurements were also made in eight children with kwashiorkor after the loss of oedema, and in sixteen children who were recovering from either marasmus or kwashiorkor.

2. The mean concentration of serum albumin was similar for children from the ‘under-nourished’ group and from the group with marasmus, but was significantly reduced in those with kwashiorkor.

3. The concentration of serum transferrin was significantly reduced in both the group of children with marasmus and those with kwashiorkor. The serum transferrin concentration was significantly lower in children with kwashiorkor when compared with the level in those with marasmus.

4. Seventeen children (seven with kwashiorkor and ten with marasmus) died. These children were neither lighter nor shorter than the severely malnourished children who survived. The concentration of serum albumin was not lower in the children who died than in those who survived.

5. In contrast to the results for serum albumin concentrations, the children who died had significantly lower levels of serum transferrin than those who survived.

6. There was a significant linear relationship between serum transferrin concentrations and the deficits in length-for-age (P< 0·05) and weight-for-length (P< 0·001) in the marginally undernourished children. The deficit in weight-for-length was also linearly related to the serum transferrin concentrations (P< 0·001) in children recovering from severe malnutrition.

7. It is suggested that the measurement of serum transferrin concentrations provides an index of severity in severely malnourished children, and should prove useful in field assessments of nutritional status.
The role of the gut microflora in the utilization of dietary urea by the chick
Authors: Okumura J. , Hewitt D. , Salter D. N. , Coates M. E.
Published: May 2019

1. In a preliminary experiment, growth of conventional chicks given a basal diet containing adequate amounts of all the essential but none of the non-essential amino acids was improved by supplements of 10·3 g urea or 50·4 g glutamic acid/kg diet or both.

2. In the main study the effects of supplementing the basal diet with 2·6 g urea/kg were compared in groups of sixteen germ-free and conventional chicks.

3. The germ-free chicks did not benefit from the urea supplement whereas the conventional birds showed improved food conversion efficiency and significantly better growth.

4. In both environments nitrogen retention ((mg N intake – mg N excreted) ÷g food intake) was higher in the birds given urea, but N utilization ((mg N intake – mg N excreted) ÷ mg N intake) was reduced. This reduction was greater in the germ-free birds.

5. There was a small increase in plasma ammonia concentration in the germ-free birds given urea but a significantly greater increase in the corresponding conventional group.

6. Plasma uric acid concentrations were variable in both groups, and much lower than the normal range. They followed a similar pattern to the plasma ammonia values.

7. More insoluble N was excreted by the conventional chicks given urea than by the corresponding germ-free group, or by either group given the basal diet.

8. It was concluded that the gut micro-organisms are responsible for the growth-promoting effect of urea, presumably through release of ammonia by bacterial urease (EC3.5.1.5) and its consequent incorporation into amino acids.
A Hand-Operated Fluid Drill for Small Plot Ess
Authors: Lickorish G.R. , Darby R.J.
Published: May 2019

Fluid-drilling is the term used to describe sowing seed in a liquid carrier. Elliot (1966) used a tractor-mounted fluid drill designed by the National Institute of Agricultural Engineering to sow normal seed into killed grassland, and a similar but modified drill was subsequently used at the National Vegetable Research Station to sow pre-germinated vegetable seeds (Gurrah et al., 1974; Gurrah, 1975). It then became necessary for compact and economical experiments to be carried out, both on and off the Station, creating a requirement for a small, portable, easily operated, hand-powered drill of simple and robust construction (Gurrah, 1975). Such a drill was built in 1975 and is described in this paper.
Political Censorship: Some Reflections on its Validity in Israel's Constitutional Law
Authors: Lahav Pnina
Published: May 2019

On 19 January 1976, the Government of Israel announced its intention to impose censorship on two categories of information:

(1) Information about the existence or content of a document relating to Israel's foreign affairs which is classified “top secret” or similarly classified and which is addressed from Israel to a foreign country or from a foreign country to Israel.

(2) Information relating to a visit by an Israeli official to a foreign country or a visit by a foreign official to Israel, or a meeting between an Israeli and a foreign official—when no diplomatic relations obtain between Israel and that country and when the visit or meeting was not conducted in public nor officially announced in Israel.

This step was the Government's response to a series of leakages which appeared in the preceding weeks in the press in Israel. Two publicized items had particularly outraged the Government. One item discussed President Ford's secret message to Prime Minister Rabin. The other item disclosed a secret visit by Foreign Minister Allon to Europe.
Effect of Herbicides on In Vivo Nitrate and Nitrite Reduction
Authors: Finke R.L. , Warner R.L. , Muzik T.J.
Published: May 2019

The effects of herbicides on in vivo nitrate and nitrite reduction were determined by vacuum infiltrating sections of barley (Hordeum vulgareL.) or bean (Phaseolus vulgarisL.) leaves with solutions containing nitrate and herbicides. Herbicides causing a reduction of nitrite accumulation in the dark were considered to have inhibitory effects upon nitrate reduction and those causing an accumulation of nitrite in the light were considered to inhibit nitrite reduction. Only dinoseb (2-sec-butyl-4,6-dinitrophenol) and potassium azide significantly reduced nitrate reduction in both barley and bean. All of the herbicides which inhibit photosynthesis inhibited nitrite reduction but had no significant effect on nitrate reduction in barley and bean. Nitrite reduction in an atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] resistant pigweed (Amaranthus retroflexusL.) biotype was not affected by any triazine tested. However, these triazines significantly inhibited nitrite reduction in barley, bean, and the susceptible pigweed biotype. The results suggest that the in vivo nitrate reductase technique may be a useful technique for identifying chemicals which inhibit the flow of electrons to ferredoxin, thereby inhibiting nitrite reduction in light.
Washing Equipment for Separating Weed Seed from Soil
Authors: Thorsen Jack A. , Crabtree Garvin
Published: May 2019

A washer was designed and tested for washing soil from weed seed buried in fabric packets and for separating weed seed from soil. The washer was constructed from inexpensive, readily available materials and was found to function efficiently.