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Editorial for advanced structural ceramics technology and characteristics

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Rare Metals 2020年第5期39卷 460-462页

作者： Jing Feng guang-Hua Liu chun-Lei Wan Faculty of materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China School of materials Science and Engineering Tsinghua UniversityBeijing 100084China

It is our great pleasure as Guest Editors of the journal‘‘Rare Metals’’to present the special issue on‘‘Advanced Structural Ceramics Technology&Characteristics.’’It provides the most recent research developments in advanced structural ceramics technology and characteristics and their applications in the potential industrial *** the twenty-first century and the following decade,industrial ceramics have made significant contributions to various fields,including electronics,communications,transports,aeronautics,astronautics,environment,and energy.

关键词： pleasure communications application

Phospholipid fatty acid patterns of microbial communities in paddy soil under different fertilizer treatments

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Journal of Environmental Sciences 2007年第1期19卷 55-59页

作者： ZHANG Qi-chun WANG guang-huo YAO Huai-ying Department of Natural Resources Zhejiang University Hangzhou 310029 China

The microbial communities under irrigated rice cropping with different fertilizer treatments, including control （CK）, PK, NK, NP, NPK fertilization, were investigated using phospholipid fatty acid （PLFA） profile method. The results of this study revealed that the fertilizer practice had an impact on the community structure of specific microbial groups. The principal components analysis （PCA） showed that proportion of the actinomycete PLFAs （10Me 18：0 and 10Me 16：0） were the lowest in the PK treatment and the highest in the NPK treatment, which means that soil nitrogen status affected the diversity of actinomycetes, whereas nitrogen cycling was related to the actinomycets. Under CK treatment, the ratio of Gram-positive to Gram-negative bacteria was lower compared with that in fertilizer addition treatments, indicating that fertilizer application stimulated Gram-positive bacterial population in paddy soil. The fatty acid 18：2to6,9, which is considered to be predominantly of fungal origin, was at low level in all the treatments. The ratio of cyl9：0 to 18：1 to7, which has been proposed as an indicator of stress conditions, decreased in PK treatment. Changes of soil microbial community under different fertilizer treatments of paddy soil were detected in this study; however, the causes that lead to changes in the microbial community still needs further study.

关键词： paddy soil fertilizers soil microorganisms community structure PLFA PCA

A Mechanism Study of a Novel Acid-Activatable Michael-Type Fluorescent Probe for Thiols

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Chinese Journal of Chemical Physics 2015年第3期28卷 277-287,I0001页

作者： Yao Tong chun-guang Dai Yi Ren Shi-wei Luo Department of Chemistry University of Science and Technology of China Hefei 230026 China College of Chemistry and State Key Laboratory of Biotherapy Sichuan University Chengdu 610064 China

A Michael addition is usually taken as a base-catalysed reaction. However, our synthesized 2-（quinolin-2-ylmethylene） malonic acid （Qma） as a Michael-type thiol fluorescent probe is acid-active in its sensing reaction. In this work, based on theoretic calculation and experimental study on 7-hydroxy-2-（quinolin-2-ylmethylene） malonic acid, we demonstrated that Qma as a Michael acceptor is acid-activatable, i.e., it works only in solutions at pH〈7, and the lower the pH of solutions is, the higher reactivity Qma has. In alkaline solution, the malonate Qma[-2H＋]2- cannot react with both RSand RSH. In contrast, 2-（quinolin-2- ylmethylene） malonic ester （QME）, the ester of Qma, reveal a contrary pH effect on its sensing reaction, that is, it can sense thiols in alkaline solutions but not in acidic solutions, like a normal base-catalysed Michael addition. The values of activation enthalpies from theoretic calculation support the above sensing behavior of two probes under different pH conditions. In acidic solutions, the protonated Qma is more highly reactive towards electrophilic attack over its other ionized states in neutral and alkaline solutions, and so can react with lowly reactive RSH. In contrast, there is a big energy barrier in the interaction of QME with RSH （acidic solutions）, and the reaction of QME with the highly reactive nucleophile RS- is a low activation energy process （in alkaline solutions）. Theoretic calculation reveals that the sensing reaction of Qma undergoes a 1,4-addition process with neutral thiols （RSH）, and a 1,2-addition pathway for the sensing reaction of QME with RS-. Therefore, the sensing reaction of Qma is an acid-catalysed Michael addition via a 1,4-addition, and a normal base-catalysed Michael addition via a 1,2-addition.

关键词： Fluorescent probe Thiols Michael addition DFT calculation Transitionstate Activation enthalpy

A novel dependency language model for information retrieval

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第6期8卷 871-882页

作者： CAI Ke-ke BU Jia-jun CHEN chun QIU guang School of Computer Science and Technology Zhejiang University Hangzhou 310027 China

This paper explores the application of term dependency in information retrieval (IR) and proposes a novel dependency retrieval model. This retrieval model suggests an extension to the existing language modeling (LM) approach to IR by introducing dependency models for both query and document. Relevance between document and query is then evaluated by reference to the Kullback-Leibler divergence between their dependency models. This paper introduces a novel hybrid dependency structure, which allows integration of various forms of dependency within a single framework. A pseudo relevance feedback based method is also introduced for constructing query dependency model. The basic idea is to use query-relevant top-ranking sentences extracted from the top documents at retrieval time as the augmented representation of query, from which the relationships between query terms are identified. A markov Random Field (MRF) based approach is presented to ensure the relevance of the extracted sentences, which utilizes the association features between query terms within a sentence to evaluate the relevance of each sentence. This dependency retrieval model was compared with other traditional retrieval models. Experiments indicated that it produces significant improvements in retrieval effectiveness.

关键词： Term dependency Language modeling (LM) Retrieval model Sentence retrieval

Homozygous phytosterolemia and a literature review:A case report

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World Journal of Clinical Cases 2025年第10期13卷 46-52页

作者： chun-Xin Jiang guang Yang Lian-Ping Shi Peng-Yu Su Department of Cardiovascular North China University of Science and Technology Affiliated HospitalTangshan 063000Hebei ProvinceChina

BACKGROUND Phytosterolemia,also known as sitosterolemia,is a rare autosomal recessive disease characterized by elevated plasma plant sterol levels and xanthomata,which is easily misdiagnosed as familial *** with homozygous phytosterolemia often have severe clinical manifestations,with xanthomata in childhood and premature *** patient had a milder clinical *** SUMmaRY This report describes a patient with homozygous phytosterolemia who presented with only elevated cholesterol and low-density lipoprotein cholesterol(LDL-C)without xanthomata,arteriosclerosis,or hematological *** mutation of ABCG5 which encodes an ATP-binding cassette transporter,was detected by whole exome sequencing and diagnosed as *** of the patient’s plasma plant sterol levels detected significant elevations in stigmasterol,rapeseed oil-derived plant sterol,andβ-glutaminol *** was started and a low plant sterol diet was *** patient’s blood lipid profile was reexamined one month later and showed significant decreases in total cholesterol and LDL-C *** has similar clinical features as familial hypercholesterolemia,is highly susceptible to misdiagnosis,and has a very low incidence,and therefore clinicians need to consider a genetic diagnosis of a definitively hyperlipidemic disorder when statin drugs fail to lower lipid *** Phytosterolemia is easily misdiagnosed as familial hypercholesterolaemia and can be treated by dietary modification and cholesterol absorption inhibitors to lower blood lipids.

关键词： Hypercholesterolemia Cholesterol Low-density lipoprotein Phytosterolemia Liquid chromatography ABCG5/ABCG8 Sitosterolemia

Neuroprotective effect of angiotensin Ⅱ type 2 receptor during cerebral ischemia/reperfusion

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Neural Regeneration Research 2016年第7期11卷 1102-1107页

作者： chun-ye ma Lin Yin Department of Neurology the Second Hospital of Dalian Medical University Dalian Liaoning Province China

Angiotensin Ⅱ type 2 receptor（AT2R） activation has been shown to protect against stroke,but its precise mechanism remains poorly *** investigated whether the protective effect of AT2 R against ischemia/reperfusion injury is mediated by the suppression of immune and inflammatory *** models of middle cerebral artery occlusion were intraperitoneally injected with physiological saline,the AT2 R agonist CGP42112（1 mg/kg per day） or antagonist PD123319（1 mg/kg per day）.In the CGP42112 group,AT2 R expression increased,the infarct area decreased,interleukin-1β and tumor necrosis factor-α expression decreased,and interleukin-10 expression increased compared with the saline *** AT2 R using PD123319 produced the opposite *** results indicate that AT2 R activation suppresses immune and inflammatory responses,and protects against cerebral ischemia/reperfusion injury.

关键词： interleukin protective saline occlusion infarct understood suppression injected poorly physiological

An improved thermometer for intermediate-mass fragments

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Nuclear Science and Techniques 2016年第6期27卷 13-16页

作者： Tian-Tian Ding chun-Wang ma Institute of Particle and Nuclear Physics Henan Normal University

An improved thermometer(TIB) is proposed for intermediate-mass fragments via the difference between isobaric yield *** residual free energy of three isobars is replaced by that of the binding *** measured fragments in the 140 A MeV ^(40,48) Ca +9Be(181Ta) and^(58,64) Ni +~9Be(^(181)Ta) reactions are analyzed to obtain T_(IB) ranging from 0.6 to 3.5 Me *** suggested to be a direct determination of temperature avoiding the fitting procedure.

关键词：温度计中间质量碎片中等质量碎片反应分析直接测定拟合程序等压线 MeV

Impact wear properties of dissimilar joints between bainitic frogs and pearlite rails

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Journal of Iron and Steel Research International 2024年第1期31卷 275-287页

作者： Pin-yong Zeng chun-guang Zuo Xiao-yu Zhang Wei Li Tribology Research Institute Southwest Jiaotong UniversityChengdu610031SichuanChina

The impact wear behavior and damage mechanism of dissimilar welded joints between U26Mn frog and U75 V rail before and after normalizing treatment were studied by cyclic impact *** experiment indicated that the impact wear volume of the joints increased with the increasing number of impact *** main wear mechanisms include pitting wear,mild fatigue wear,delamination wear,and fatigue wear,and plastic deformation was the primary impact wear *** them,fatigue wear had the greatest influence on wear volume,while other wear mechanisms had limited *** impact wear resistance of the base material was better than that of the heat-affected *** treatment was beneficial to improving the impact wear resistance of welded joints owing to its effect to promote pearlite recovery,grain refinement,and uniform distribution of *** martensite generated in the rail welded joints aggravated the impact wear damage to the materials,which should be avoided.

关键词： Dissimilar welded joint Impact wear Bainitic steel Damage mechanism Wear rate

Heat transfer and plume statistics in turbulent thermal convection with sparse fractal roughness

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Journal of Hydrodynamics 2021年第5期33卷 1065-1077页

作者： guang-chun Xu Qi Wang Zhen-hua Wan De-jun Sun Department of Modern Mechanics University of Science and Technology of ChinaHefei 230027China

Rough-surface Rayleigh-Benard convection is investigated using direct numerical simulations in two-dimensional convection cells with aspect ratioГ=*** types of fractal roughness elements,which are marked as nl,n2 and n3,are constructed based on the Koch curve and sparsely mounted on both the plates,where n denotes the level of the *** considered Rayleigh numbers Ra range from 10^(7)to 10^(11)with Prandtl number Pr=*** regimes are identified for cases nl,*** Regime I,the scaling exponentsβin the effective Nusselt number Nu vs Ra scaling Nu~Ra^(β)reach up to about ***,when Ra is larger than a critical value Ra_(c),the flow enters RegimeⅡ,with p saturating back to a value close to the smooth-wall case(0.3).Rac is found to increase with increasing n,and for case n3,only Regime I is identified in the studied Ra *** extension of Regime I in case n3 is due to the fact that at high Ra,the smallest roughness elements can play a role to disrupt the thermal boundary *** thermal dissipation rate is studied and it is found that the increasedβin Regime I is related with enhanced thermal dissipation rate in the *** interesting finding is that no clear convection roll structures can be identified for the rough cases,which is different from the smooth case where well-organized convection rolls can be *** difference is further quantified by the detailed analysis of the plume statistics,and it is found that the horizontal profiles of plume density and velocity are relatively flattened due to the absence of clear convection rolls.

关键词： Thermal convection Rayleigh-Benard convection rough surface Introduction