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Research progress of catalysts for direct coal liquefaction

Journal of Energy Chemistry 2025年第1期100卷 481-497页

作者： Wei Song Penggao Liu Xinyue Chen Ting Wang Chunrong He Rui Hao Kaiyu Liu State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of Chemistry Xinjiang University College of Chemistry and Chemical Engineering Henan Polytechnic University Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical Engineering Central South University

Coal direct liquefaction technology is a crucial contemporary coal chemical technology for efficient and clean use of coal resources. The development of direct coal liquefaction technology and the promotion of alternative energy sources are important measures to guarantee energy security and economic security. However, several challenges need to be addressed, including low conversion rate, inadequate oil yield, significant coking, demanding reaction conditions, and high energy consumption. Extensive research has been conducted on these issues, but further exploration is required in certain aspects such as pyrolysis of macromolecules during the liquefaction process, hydrogen activation, catalysts' performance and stability, solvent hydrogenation, as well as interactions between free radicals to understand their mechanisms better. This paper presents a comprehensive analysis of the design strategy for efficient catalysts in coal liquefaction, encompassing the mechanism of coal liquefaction, catalyst construction,and enhancement of catalytic conversion efficiency. It serves as a comprehensive guide for further research endeavors. Firstly, it systematically summarizes the conversion mechanism of direct coal liquefaction, provides detailed descriptions of various catalyst design strategies, and especially outlines the catalytic mechanism. Furthermore, it addresses the challenges and prospects associated with constructing efficient catalysts for direct coal liquefaction based on an understanding of their action mechanisms.

关键词： Direct coal liquefaction Catalysts Mechanism of action Solvent hydrogenation

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Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 70-79页

作者： Yong Hou Shuo Zhang Jie Dang Jia Guo Hanghang Zhou Xuewei Lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this *** most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina *** results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO *** transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO *** of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents *** analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO ***,bond strength is another important factor affecting the slag *** occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.

关键词： aluminosilicate viscosity structure spectroscopy

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Tameness does not correlate with the learning of an appetitive association in a wild canid

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Current Zoology 2019年第1期65卷 61-65页

作者： Matthew B. Petelle Stephanie Periquet Aliza le Roux Department of Zoology and Entomology University of Free State Qwaqwa Campus Private Bag X13 Phuthaditjhaba Free State 9866 South Africa

Individual differe nces in cog nition have been shown to be common in some animal taxa, and recent evidenee suggests that an individual's personality can be associated with an individuads cognitive strategy. We tested whether wild bat-eared foxes Otocyon megalotis differ in a risktaking behavior (tameness) and whether this trait correlated with appetitive association learning performanee. While our result shows that individuals differed in their tameness, we found no associati on between this personality trait and learning the appetitive association. This result does not support the framework that differe nces in cog nition are associated with differe nces in personality;however, our small sample size does not allow us to assert that pers on ality can not be associated with cog nition in this system. This study highlights that measuri ng cog nition and pers on ality in wild systems presents added difficulty and that correlations found in captive animals may not be evident in their wild counterparts.

关键词： carnivore cognition bat-eared fox personality Individuals

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Precise role of H pylori in duodenal ulceration

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World Journal of Gastroenterology 2006年第40期12卷 6413-6419页

作者： Michael Hobsley Frank I Tovey John Holton Department of Surgery Royal Free and University College Medical School London United Kingdom Department of Microbiology Royal Free and University College Medical School London United Kingdom

The facts that H pylori infection is commoner in duodenal ulcer (DU) patients than in the normal population, and that eradication results in most cases being cured, have led to the belief that it causes DU. However, early cases of DU are less likely than established ones to be infected. H pylori-negative cases are usually ascribed to specific associated factors such as non-steroidal anti-inflammatory drugs (NSAIDs), Crohn’s disease, and hypergastrinaemia, but even after excluding these, several H pylori-negative cases remain and are particularly common in areas of low prevalence of H pylori infection. Moreover, this incidence of H pylori negative DU is not associated with a fall in overall DU prevalence when compared with countries with a higher H pylori prevalence. In countries with a high H pylori prevalence there are regional differences in DU prevalence, but no evidence of an overall higher prevalence of DU than in countries with a low H pylori prevalence. There is no evidence that virulence factors are predictive of clinical outcome. After healing following eradication of H pylori infection DU can still recur. Medical or surgical measures to reduce acid output can lead to long-term healing despite persistence of H pylori infection. Up to half of cases of acute DU perforation are H pylori negative. These findings lead to the conclusion that H pylori infection does not itself cause DU, but leads to resistance to healing, i.e., chronicity. This conclusion is shown not to be incompatible with the universally high prevalence of DU compared with controls.

关键词： Duodenal ulceration H pylori infection Not causal Delays healing

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Metcalfe＇s Law and Network Quality： An Extension of Zhang et al.

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Journal of Computer Science & Technology 2016年第1期31卷 117-123页

作者： Leo Van Hove Department of Applied Economics (APEC) Vrije Universiteit Brussel (Free University of Brussels) Brussels 1050 Belgium

Zhang et al. exploited data on Facebook and Tencent to validate Metcalfe＇s law, which states that the aggregate value of a communications network is proportional to the square of the number of users. This note points out that the value of a social network may be driven not only by its size, but also by increases in the variety and quality of the services offered. I therefore extend Zhang et al.＇s approach by explicitly controlling for changes in network quality over time. For the case of Tencent, I also filter out revenues and costs that are unrelated to Tencent＇s core （social network） services. I find that these two extensions only strengthen Zhang et al.＇s conclusions： Metcalfe＇s law now outperforms the other laws even more clearlv.

关键词： Metcalfe's law network value Facebook Tencent quality cost of revenue

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Earnings Inequality in Germany and Its Implications

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Economic and Political Studies 2015年第2期3卷 60-84页

作者： GIACOMO CORNEO the Department of Economics Free University of Berlin

The current paper discusses the evolution of earnings inequality in Germany with an eye to its potential lessons for China. Inequality is assessed from two different perspectives: the distribution of annual earnings, and the distribution of lifetime earnings. This paper proposes to implement closer monitoring of lifetime earnings and take a proactive stance in the formation of the wage-bargaining regime.

关键词： earnings inequality labor market institutions Germ

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Laboratory vs. Field Calibration of HydraSCOUT Probes for Soil Water Measurement

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Pedosphere 2019年第1期29卷 132-136页

作者： Cinisani M.TFWALA Leon D.van RENSBURG Zaid A.BELLO Pieter C.ZIETSMAN Department of Soil Crop & Climate Sciences University of the Free State Department of Botany National Museum(South Africa) Centre for Environmental Management University of the Free State

Dear Editor,Accurate measurement of volumetric soil water content(θ_v)is essential for efficient soil water ***(HS)probes are capacitance-type probes forθ_v measurement with high accuracy,but require calibration for... 详细信息

关键词： Field Calibration of HydraSCOUT Probes for Soil Water Measurement Laboratory vs

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Electrochemical response of Nd3+ ions containing lithium borate glasses

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Journal of Rare Earths 2017年第5期35卷 480-484页

作者： D.D.Ramteke H.C.Swart R.S.Gedam Department of Physics University of the Free State Department of Applied Physics Visvesvaraya National Institute of Technology

The present investigation was to understand the electrical properties of 27.5 Li2O-（72.5–x） B2O3-xNd2O3with x=0.5, 1, 1.5 and 2 glasses. We analyzed the impedance data for a wide frequency range to get inside the conduction phenomenon. The conductivity of the glasses decreased due to the decrease in the mobility of mobile Li+ions. This decrease was due to polymerization of glass network caused by the Nd3+ions. Modulus formalism confirmed that the Li+ions overcame the same barrier no matter whether it took part in the conduction process or relaxation process. Scaling of the electrochemical data showed that conduction process in the ion conducting glasses was composition dependent and not the temperature dependent.

关键词： glasses impedance spectroscopy electrical properties modulus formalism scaling rare earths

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Male factor infertility and ART

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Asian Journal of Andrology 2012年第1期14卷 103-108,178页

作者： Herman Tournaye Centre for Reproductive Medicine University Hospital of the Dutch-speaking Brussels Free University Brussels B-1090 Belgium

For years, the management and treatment of male factor infertility has been ‘experience＇ and not ‘evidence＇ based. Although not evidence-based, current clinical practice involves extensive use of assisted reproductive techniques （ART）. Where specific treatments are not indicated or have failed, ART have become popular adjunctive treatments for alleviating male factor infertility. According to the limited evidence available, intrauterine insemination （IUI） may be considered as a first-line treatment in a couple in which the female partner has a normal fertility status and at least 1 × 10^6 progressively motile spermatozoa are recovered after sperm preparation. If no pregnancy is achieved after 3-6 cycles of IUI, optimized in vitro fertilization （IVF） can be proposed. When less than 0.5× 106 progressively motile spermatozoa are obtained after seminal fluid processing or sperm are recovered surgically from the testis or epididymis, intracytoplasmic sperm injection （ICSI） should be performed. Although the outcome of no other ART has ever been scrutinized as much before, no large-scale ‘macroproblems＇ have as yet been observed after ICSI. Yet, ICSI candidates should be rigorously screened before embarking on IVF or ICSI, and thoroughly informed of the limitations of our knowledge on the hereditary aspects of male infertility and the safety aspects of ART.

关键词： artificial intracytoplasmic sperm injection insemination in vitro fertilization male infertility sperm

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Pyrrolidine dithiocarbamate reduces ischemia-reperfusion injury of the small intestine

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World Journal of Gastroenterology 2005年第46期11卷 7308-7313页

作者： Ismail H Mallick Wen-Xuan Yang Marc C Winslet Alexander M Seifalian GI and Hepatobiliary Research Unit University Department of Surgery Royal Free and University College Medical School University College London LondonUnited Kingdom Department of Surgery Royal Free Hospital Hampstead NHS Trust London United Kingdom

AIM： To evaluate whether pyrrolidine dithiocarbamate （PDTC）, an enhancer of HO production, attenuates intestinal IR injury. METHODS： Eighteen male rats were randomly allocated into three groups：（a） sham; （b） IR, consisting of 30 min of intestinal ischemia, followed by 2-h period of reperfusion; and （c） PDTC treatment before IR. Intestinal microvascular perfusion （IMP） was monitored continuously by laser Doppler flowmetry. At the end of the reperfusion, serum samples for lactate dehydrogenase （LDH） levels and biopsies of ileum were obtained. HO activity in the ileum was assessed at the end of the reperfusion period. RESULTS： At the end of the reperfusion in the IR group, IMP recovered partially to 42.5% of baseline （P〈0.05 vs sham）, whereas PDTC improved IMP to 67.3% of baseline （P〈0.01 vs IR）. There was a twofold increase in HO activity in PDTC group （2 062.66±106.11） as compared to IR （842.3±85.12）（P〈0.001）. LDH was significantly reduced （P〈0.001） in PDTC group （585.6±102.4） as compared to IR group （1 973.8±306.5）. Histological examination showed that the ileal mucosa was significantly less injured in PDTC group as compared with IR group. CONCLUSION： Our study demonstrates that PDTC improves the IMP and attenuates IR injury of the intestine possibly via HO production. Additional studies are warranted to evaluate the clinical efficacy of PDTC in the prevention of IR injury of the small intestine.

关键词： Intestine Ischemia-reperfusion injury Heme oxygenase Pyrrolidine

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