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Characteristics of high-rank coal structure parallel and perpendicular to the bedding plane via NMR and X-ray CT

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Petroleum Science 2020年第4期17卷 925-938页

作者： Shi-qi Liu shu-Xun Sang qiu-Jia Hu hui-Huang Fang Low Carbon Energy Institute China University of Mining and TechnologyXuzhou 221008China Jiangsu Key Laboratory of Coal-based Greenhouse Gas Control and Utilization China University of Mining and TechnologyXuzhou 221008China School of Mineral Resource and Geoscience China University of Mining and TechnologyXuzhou 221116China Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process Ministry of EducationChina University of Mining and TechnologyXuzhou 221008China Shanxi CBM Branch of Huabei Oilfeld Company China National Petroleum CorporationJincheng 048000China

Pores and fractures and their connectivity play a significant role in coalbed methane *** investigate the growth characteristics and connectivity of pores and fractures in coal parallel and perpendicular to the bedding plane,the pores and fractures of high-rank coal samples collected from the southern qinshui Basin were measured by low-field nuclear magnetic resonance,X-ray-computed tomography and field emission scanning electron ***,the determinants of their connectivity were further *** results show that the high-rank coal samples have similar pore size distributions both parallel and perpendicular to the bedding *** primarily contain mesopores(2-50 nm in width),followed by macrospores(> 50 nm in width).The research indicated that the high-rank coal connectivity parallel to the bedding plane is significantly better than that perpendicular to the bedding *** connectivity of high-rank coal is mainly determined by throats,and the orientation of the pores and *** two connectivity modes in high-rank coal are "pore connectivity," in which the throats are mainly pores with a low coordination number,and "microfissure connectivity",in which the throats are mainly microfissures with a high coordination number.

关键词： Porosity Connectivity Pore width Microfissure High-rank coal qinshui Basin

Theoretical investigations on the thiol–thioester exchange steps of different thioesters

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Chinese Chemical Letters 2015年第10期26卷 1259-1264页

作者： Xiao-hui Sun Hai-Zhu Yu shu-qi Pei Zhi-Min Dang Department of Polymer Science and Engineering University of Science and Technology Beijing Department of Chemistry and Centre for Atomic Engineering of Advanced Materials Anhui University

As the rate-determining step in native chemical ligation reactions, the thiol–thioester exchange step is important in determining the efficiency of the ligations of peptides. In the present study, systematic theoretical calculations were carried out on the relationships between the structure of different thioesters and the free energy barriers of the thiol–thioester exchange step. According to the calculation results, the thiol–thioester exchange step is disfavored by the steric hindrance around the carbonyl center, while the electronic effect（i.e. conjugation and hyper-conjugation effects） becomes important when the steric hindrance is insignificant.

关键词： Native chemical ligation Thiol–thioester exchange Density functional theory

Grafting Increases the Copper Tolerance of Cucumber Seedlings by Improvement of Polyamine Contents and Enhancement of Antioxidant Enzymes Activity

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Agricultural Sciences in China 2010年第7期9卷 985-994页

作者： ZHANG Zi-kun LIU Shi-qi HAO shu-qin LIU Su-hui State Key Laboratory of Crop Biology/Key Laboratory of Horticultural Crop Biology College of Horticulture Science and Engineering Shandong Agricultural University Tai＇an 271018 P.R. China

The aim of the study is to determine whether grafting could improve antioxidant enzyme activities and polyamine contents in leaves of cucumber plants（Cucumis sativus ***） under copper ***（using Cucurbita ficifolia as rootstock） and ungrafted cucumber seedlings were cultured in deep flow technique（DFT） with the Cu2＋ concentration of 40 μmol *** results showed that on the 9th day of copper stress treatment,the contents of malondialdehyde（MDA） and hydrogen peroxide（H2O2）,superoxide radical（） producing rate,and electrolyte leakage percentage were significantly lower in grafted seedlings in comparison to those of the ungrafted seedlings,whereas the activities of antioxidants such as superoxide dismutase（SOD,EC 1.***.1.1）,peroxidase（POD,EC 1.***.1.7）,ascorbate peroxidase（APX,EC 1.***.1.11）,catalase（CAT,EC 1.***.1.6）,glutathione reductase（GR,EC 1.***.4.2）,and monodehydroascorbate reductase（MDHAR,EC 1.***.5.4） of grafted seedlings were also significantly higher than that of ungrafted seedlings,and the contents of free proline and soluble protein of grafted seedlings were significantly higher than that of ungrafted ***2＋ treatment increased the putrescine（Put） level and lowered the spermidine（Spd） and spermine（Spm） levels,thereby reducing the Put/（Spd ＋ Spm） ratio in leaves of grafted and ungrafted *** markedly reversed these Cu-induced effects for all three PAs and partially restored the Put/（Spd ＋ Spm） ratio in *** results suggest that grafting can enhance the tolerance of cucumber seedlings to Cu2＋ stress by increasing the activities of antioxidants and the levels of endogenous Spd and Spm,decreasing the Put/（Spd ＋ Spm） ratio and the levels of ROS,promoting free proline and soluble protein synthesis in cucumber seedling leaves.

关键词： copper stress grafted cucumber seedling antioxidant enzymes polyamines lipid peroxidation

Enantioselective reductive conjugate alkenylation of α,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第01期 157-162页

作者： Rong-De He Yun-Lei Luo qiu-Quan Pan qi-Wei Yao Xing-Zhong shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis, yet their asymmetric variant remains elusive. Concurrently, asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–M. This manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl acetates. The method facilitates the enantioselective addition of keto alkenyl groups to α,β-enones, resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access otherwise. The use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

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沥青路面裂缝高聚物注浆效果试验评价研究

山西建筑 2025年第2期51卷 129-132页

作者：祁敏曾辉江苏路通装配科技有限公司江苏宜兴214200 江苏众智交通创新产业研究院有限公司江苏南京211899

非开挖式注浆技术采用高聚物双组分材料注浆,能有效填充沥青路面裂缝处半刚性基层和底基层层间脱空,排出结构层水分,密封裂缝,达到补强路面结构层效果。为了评价注浆技术应用效果,通过施工过程注浆孔检测、注浆前后探地雷达图谱测试、... 详细信息

非开挖式注浆技术采用高聚物双组分材料注浆,能有效填充沥青路面裂缝处半刚性基层和底基层层间脱空,排出结构层水分,密封裂缝,达到补强路面结构层效果。为了评价注浆技术应用效果,通过施工过程注浆孔检测、注浆前后探地雷达图谱测试、弯沉测试以及取芯等方式来评判,结果显示注浆后裂缝处弯沉能降低20%,两侧弯沉差明显减小,三维探地雷达检测显示裂缝注浆后灰度图内部未出现异常信号,无振幅加强现象,证明裂缝处浆液被填充。

关键词：非开挖注浆高聚物半刚性基层三维探地雷达横向裂缝

Melanization induced by Heliothis virescens ascovirus 3h promotes viral replication

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Insect Science 2021年第2期28卷 472-484页

作者： Zi-qi Li Xiao-hui Song Min Wang shu Wang Guo-Hua Huang Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests Hunan Agricultural UniversityChangshaChina College of Plant Protection Hunan Agricultural UniversityChangshaChina

Melanization is an important innate immune defense mechanism of insects,which can kill invading *** pathogens,for their survival and reproduction,inhibit the melanization of the ***,our results suggested that after infection with Heliothis virescens ascovirus 3h(HvAV-3h),the speed of melanization in infected Spodoptera exigiia larval hemolymph was accelerated and that the phenoloxidase(PO)activity of hemolymph in larvae infected with HvAV-3h increased significantly(1.20-fold at 96 hpi,1.52-fold at 120 hpi,1.23-fold at 144 hpi,1.12-fold at 168 hpi).The transcription level of the gene encoding *** prophenoloxidase-1(SePPO-1 gene)was upregulated dramatically in the fat body during the middle stage of *** addition,when melanization was inhibited or promoted,the replication of HvAV-3h was inhibited or promoted,*** conclusion,infection with HvAV-3h can markedly induce melanization in the middle stage of infection,and melanization is helpful for HvAV-3h viral replication.

关键词： Heliothis virescens ascovirus 3h melanization Spodoptera exigua viral replication

Protective effect of Yi-qi-Huo-Xue Decoction against ischemic heart disease by regulating cardiac lipid metabolism

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Chinese Journal of Natural Medicines 2020年第10期18卷 779-792页

作者： LI Fang-He HUANG Xiao-Lou WANG hui GUO shu-Wen LI Ping The Third Affiliated Hospital Beijing University of Chinese MedicineBeijing 100029China School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing 100029China College of Acupuncture and Orthopedics Guizhou University of Traditional Chinese MedicineGuiyang 550025China Fangshan Hospital Beijing University of Chinese MedicineBeijing 102400China

Yi-qi-Huo-Xue Decoction(YQHX)is the recombination of Dang-Gui-Bu-Xue Decoction(DBD),which is one of the well-known traditional Chinese Medicine(TCM)prescription,and has long been shown to have significant protective effects against myocardial ischemic *** previous studies,we found that YQHX could regulate lipid and glucose metabolism,promote angiogenesis,attenuate inflammatory response,and ameliorate left ventricular function in myocardial ischemia rat ***,the underlying mechanism of how YQHX involves in lipid metabolism remains unclear so *** this study,the underlying mechanism of YQHX in lipid metabolism disorders was elucidated in a myocardial ischemia rat model and a hypoxia-induced H9 c2 cell injury ***(8.2 g·kg-1)and positive-control drug trimetazidine(10 mg·kg-1)were administered daily on the second day after left anterior descending(LAD)*** 7 days and 28 days after surgery,changes of cardiac morphology,structure,and function were evaluated by H&E staining and echocardiography,*** plasma lipid levels and mitochondrial ATP content were also *** blot and RT-PCR were used to determine the protein and mRNA expressions of AMPK,PGC-1α,CPT-1α,and PPARα.YQHX improved cardiac function and ameliorated lipid metabolism ***,YQHX increased the expression of p-AMPK,PGC-1α,and CPT-1αwithout changing PPARαin ischemic rat *** vitro,YQHX activated the protein and mRNA expression of PGC-1α,CPT-1α,and PPARαin hypoxia-induced H9 c2 cells injury,whereas AMPK inhibitor Compound c blocked the effects of *** together,the results suggest that YQHX reduces lipid metabolism disorders in myocardial ischemia via the AMPK-dependent signaling pathway.

关键词： Yi-qi-Huo-Xue Decoction Lipid metabolism Ischemic heart disease AMPK-dependent pathway Fatty acid oxidation

Characterization of metal element distributions in the rat brain following ischemic stroke by synchrotron radiation microfluorescence analysis

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Nuclear Science and Techniques 2020年第10期31卷 1-12页

作者： shu-Peng Shi hui Wang Zhuo-hui Chen Xiao-Han Li Shi-Xin Liu Meng-qi Zhang Department of Neurology Xiangya HospitalCentral South UniversityChangsha 410008China National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangsha 410008China

Ischemic stroke is one of the leading causes of death worldwide,and effective treatment strategies in the chronic phase of this disease remain *** of metals in the brain plays an important role in maintaining normal brain ***,the dynamic spatial distributions of iron,zinc,calcium,potassium,and copper in a rat brain following ischemic stroke and the association between structural distribution and function remain to be *** this study,we used a synchrotron radiation-based micro-X-ray fluorescence technique to image element mapping changes in special rat brain regions after ischemic stroke,showing the distribution characteristics of iron,zinc,calcium,potassium,and *** demonstrated,for the first time,the consistent dynamic spatial distributions of metal elements at a series of time points(3 h,4.5 h,6 h,12 h,1 d,3 d,5 d,7 d,10 d,14 d,28 d)after brain ischemia,which revealed that the homeostasis of iron,zinc,calcium,potassium,and copper in the brain was disturbed with distinctive change trends,providing clear insights in understanding the underlying pathogenesis of stroke from a novel perspective,thus laying the foundation of further developing new drug targets for stroke treatment.

关键词： Ischemic stroke Synchrotron radiation X-ray fluorescence Metal Rat brain

Visible-light-responsive homologous heterostructure of oxynitrides constructed to boost charge separation and water splitting

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Science China Chemistry 2025年第01期 186-191页

作者： Hai Zou Yunfeng Bao Xueshang Xin Yu qi Tengfeng Xie Fuxiang Zhang State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences School of Chemistry and Chemical Engineering Liaoning Normal University College of Chemistry Jilin University

Constructing type II heterostructures represents a widely recognized strategy for enhancing charge separation and photocatalytic efficiency,but it remains challenging to fabricate homologous heterostructures based on visible-light-responsive semiconductors,especially for popularly investigated （oxy）nitrides with low thermal ***,we synthesized a homologous heterostructure （denoted as YTON＿H） based on the oxynitrides of YTaO4-xNyand YTa *** heterostructure exhibits type II band structure alignment and intimate interface achieved through a magnesium （Mg） powder-assisted nitridation *** with widely reported heterologous heterostructures,the as-obtained YTON＿H homologous heterostructure could similarly exhibit enhanced charge separation as well as photocatalytic water splitting performance with respect to its counterparts(YTaO4-xNyand YTaON2).Meanwhile,detailed structural characterizations and spectroscopy analysis have been made to confirm the formation of heterostructure and promotion of spatial charge separation.

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