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Science China Earth Sciences 2025年第1期68卷 237-252页

作者： Dandan SONG Ping guan Chi zhang Jiahao ren School of Earth and Space Sciences Peking University

Helium transport through nanoscale inorganic mineral pores and pore throats is essential for its overall migration. To elucidate helium's transport dynamics within nanopores, we employed equilibrium and non-equilibrium molecular dynamics simulations to investigate helium's static self-diffusion and pressure-driven flow in quartz slit-shaped nanopores. We also introduced water and various gases, including hydrogen, methane, ethane, nitrogen, and carbon dioxide, into the nanopores to assess their influence on helium transport. Our findings indicate minimal helium adsorption on quartz pore surfaces. Under conditions where the pore size is less than 5 nm and the pressure under 10 MPa, environmental factors markedly influence helium diffusion. Large pore sizes, high temperatures, and low gas pressures enhance helium desorption and facilitate faster diffusion. We observed a positive correlation between helium flow velocity and factors such as pore size, pressure gradient, and surface smoothness of the pores. Notably, the presence of pore water and carrier gases in quartz nanopores, which diffuse more slowly than helium, tends to reduce helium surface adsorption and slow its diffusion. Among the carrier gases studied, nitrogen showed similar adsorption capacity, diffusivity, and stability to helium, while carbon dioxide displayed the highest adsorption capacity and the slowest diffusion rate, markedly differing from helium. Based on the simulation results, we concluded that water and carrier gases primarily function as transport mediums in helium migration, moving together with helium. Nitrogen, which shares similar properties with helium, effectively assists in this co-migration process. Conversely, carbon dioxide, due to its high adsorption capacity and slow diffusion, tends to be lost during co-migration. As a result, gas reservoirs with high nitrogen levels and low carbon dioxide levels are more likely to have higher helium concentrations. Additionally, the smaller por

关键词： Helium transport Slit nanopores Molecular dynamics simulations Diffusion Flow carriers

Xiao-Xu-Ming decoction extract regulates differentially expressed proteins in the hippocampus after chronic cerebral hypoperfusion

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Neural Regeneration Research 2019年第3期14卷 470-479页

作者： Yue-hua Wang Ying-Lin Yang Xiao cheng jun zhang Wan Li guan-hua du State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing Key Laboratory of Drug Target Identification and Drug Screening Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College

Xiao-Xu-Ming decoction has been widely used to treat stroke and sequelae of stroke. We have previously shown that the active fractions of Xiao-Xu-Ming decoction attenuate cerebral ischemic injury. However, the global protein profile and signaling conduction pathways regulated by Xiao-Xu-Ming decoction are still unclear. This study established a two-vessel occlusion rat model by bilateral common carotid artery occlusion. Rats were intragastrically administered 50 or 150 mg/kg Xiao-Xu-Ming decoction for 4 consecutive weeks. Learning and memory abilities were measured with Morris water maze. Motor ability was detected with prehensile test. Coordination ability was examined using the inclined screen test. Neuronal plasticity was observed by immunofluorescent staining. Differentially expressed proteins of rat hippocampus were analyzed by label-free quantitative proteomics. Real time-polymerase chain reaction and western blot assay were used to identify the changes in proteins. Results showed that Xiao-Xu-Ming decoction dramatically alleviated learning and memory deficits, and motor and coordination dysfunction, and increased the expression of microtubule-associated protein 2. Xiao-Xu-Ming decoction extract remarkably decreased 13 upregulated proteins and increased 39 downregulated proteins. The regulated proteins were mainly involved in oxidation reduction process, intracellular signaling cascade process, and protein catabolic process. The signaling pathways were mainly involved in ubiquitin mediated proteolysis and the phosphatidylinositol signaling system. Furthermore, there was an interaction among Rab2 a, Ptpn1, Ppm1 e, Cdk18, Gorasp2, Eps15, Capza2, Syngap1 and Mt-nd1. Protein analyses confirmed the changes in expression of MTND1. The current findings provide new insights into the molecular mechanisms of Xiao-Xu-Ming decoction extract's effects on chronic cerebral hypoperfusion.

关键词： nerve regeneration chronic cerebral hypoperfusion vascular dementia bilateral common carotid artery occlusion Xiao-Xu-Ming decoction label-free quantitative proteomics Morris water maze test Nano-LC-ESI LTQ-Orbitrap MS/MS technology neural regeneration

Comparison of preventive and therapeutic effect on cardio-cerebral ischemic disease between salvianolic acids and aspirin

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中国药理学与毒理学杂志 2018年第4期32卷 334-335页

作者： jun-tian zhang Shi-feng CHU guan-hua du Institute of Materia Medica Chinease Academy of Medical Sciences Beijing 100050 China

Aspirin(AS) has been widely used globally for preventing incidence of cardio-cerebral ischemic disease for nearly 100 *** people who takes AS for long term may reach several *** million,but many persons were died from interned *** found salvianolic acids(salvianolic acid B 57%,salvianolic acid A 1%,rosmarinic acid,35%,SA) was much better than AS in preventing *** of cardio-cerebral ischemic disease,and may avoid hemorrhage risk in clinical *** research are summary briefly as follows:(1) both AS and AS have same anti-platelet aggregation ***,but their mechanism is *** inhibited both TXA2 and PGI2,SA inhibited TXA2 only;(2) For established thrombosis,SA could dissolved it,AS showed no *** thrombolytic mechanism of SA has been elucidated.(3) In SHRSP rats,the incidence of stroke and death rate in SA group was distinct less that of AS group;(4) In MCAO rats,SA and Sal B decreased stroke index and neural *** showed no such ability;(5) There is microcirculatory disturbance in cardio-cerebral ischemic *** could improve circulatory disturbance induced by LPS,adrenaline,ROS and I/*** is no any paper reported AS could have beneficial effect on above mentioned microcirculatory *** models;(6) Hyperlipidemia is an independent risk factor for cardio-cerebral vascular *** could significant hypolipidemic effect which is similar to that of statins(atovastin and simvastin) and ten times stronger than *** has no inhibitory effect on hyperlipidemia.(7) Thereis *** of ROS induced by ischemic/reperfusion in cardio-cererbal vascular *** showed more ***,anti-oxidant capacity than VitC,Vit E,melatonin,edalavone and resveratrol,*** is one of the most powerful anti-oxidant in the world so far.(8) According to literatures,1/3 patients who take AS for long time will have hemorrhage,we found in normal rats and mice(coagulating and hemodynamics)SA had no apparent effect

关键词：阿司匹林心脑血管发展现状治疗方法

Fingerprinting Analysis of Saposhnikovia divaricata using ~1H Nuclear Magnetic Resonance Spectroscopy and High Performance Liquid Chromatography

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Journal of Integrative Plant Biology 2010年第9期52卷 782-792页

作者： Yue-Yang Xin An-jun deng guan-hua du Jin-Lan zhang Hai-Lin Qin Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine Ministry of Education & Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

The 1H nuclear magnetic resonance （1H NMR） fingerprints of fractionated non-polar and polar extracts （control substance for plant drug [CSPD] A and B） from the roots of 12 specimens of Saposhnikovia divaricata （Turcz.） Schischk were achieved with Fourier Transform （FT）-NMR spectrometer and assigned by comparison to each other and to the 1H NMR spectra of the isolated individual compounds. These fingerprints were found to be uniform in terms of the specificity for the implication of all 12 specimens being systematically of the same origin. The uniformity was further affirmed by high performance liquid chromatography （HPLC）, which also revealed exactly identical specificity for the identified S. divaricata species with the 1H NMR appearances of corresponding CSPD on the part of the composition of characteristic constituents when comparing to corresponding individual compounds. This investigation unambiguously shows that the specific signals from the chemotaxonomically significant compounds of chromones and coumarins in S. divaricata are exhibited distinctively in the composite features of both 1H NMR fingerprints and HPLC profiles. The 1H NMR and HPLC profiles established can successfully be used as reference for the authentication of the origin of S. divaricata species as well as for chemotaxonomic studies.

关键词： Polarity Optical properties individual Provenance Species Hplc

SnS_2 nanosheets arrays sandwiched by N-doped carbon and TiO_2 for high-performance Na-ion storage

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Green Energy & Environment 2018年第1期3卷 42-49页

作者： Weina ren Haifeng zhang Cao guan Chuanwei cheng Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology School of Physics Science and EngineeringTongji University department of Materials Science and Engineering National University of Singapore The Institute of Dongguan-Tongji University

In this paper, SnS_2 nanosheets arrays sandwiched by porous N-doped carbon and TiO_2(TiO_2@SnS_2@N-C) on flexible carbon cloth are prepared and tested as a free-standing anode for high-performance sodium ion batteries. The as-obtained TiO_2@SnS_2@N-C composite delivers a remarkable capacity performance(840 mA h g^(-1) at a current density of 200 mA g^(-1)), excellent rate capability and long-cycling life stability(293 mA h g^(-1) at 1 A g^(-1) after 600 cycles). The excellent electrochemical performance can be attributed to the synergistic effect of each component of the unique hybrid structure, in which the SnS_2 nanosheets with open framworks offer high capacity, while the porous N-doped carbon nanoplates arrays on flexible carbon cloth are able to improve the conductivity and the TiO_2 passivation layer can keep the structure integrity of SnS_2 nanosheets.

关键词： Sandwich structure SnS2 nanosheets N-doped carbon TiO2 Sodium-ion battery

Identification of multi-target anti-cancer agents from TCM formula by in silico prediction and in vitro validation

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Chinese Journal of Natural Medicines 2022年第5期20卷 332-351页

作者： zhang Bao-Yue ZHENG Yi-Fu ZHAO jun KANG de WANG Zhe XU Lv-Jie LIU Ai-Lin du guan-hua State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China School of Life Sciences Tsinghua UniversityBeijing 100084China

Cancer is a complex disease associated with multiple gene mutations and malignant phenotypes,and multi-target drugs provide a promising therapy idea for the treatment of *** products with abundant chemical structure types and rich pharmacological characteristics could be ideal sources for screening multi-target antineoplastic *** this paper,50 tumor-related targets were collected by searching the Therapeutic Target Database and Thomson Reuters Integrity database,and a multi-target anti-cancer prediction system based on mt-QSAR models was constructed by using naïve Bayesian and recursive partitioning algorithm for the first *** the multi-target anti-cancer prediction system,some dominant fragments that act on multiple tumor-related targets were analyzed,which could be helpful in designing multi-target anti-cancer ***-cancer traditional Chinese medicine(TCM)and its natural products were collected to form a TCM formula-based natural products library,and the potential targets of the natural products in the library were predicted by multi-target anti-cancer prediction *** a result,alkaloids,flavonoids and terpenoids were predicted to act on multiple tumor-related *** predicted targets of some representative compounds were verified according to literature review and most of the selected natural compounds were found to exert certain anti-cancer activity in vitro biological *** conclusion,the multi-target anti-cancer prediction system is very effective and reliable,and it could be further used for elucidating the functional mechanism of anti-cancer TCM formula and screening for multi-target anti-cancer *** anti-cancer natural compounds found in this paper will lay important information for further study.

关键词： Cancer Multi-target mt-QSAR model Nave Bayesian Recursive partitioning TCM formulae

The extract of Ramulus Cinnamom attenuates inflammatory injury induced by LPS via regulation of TLR4/MyD88 signaling pathway in BV2 cells

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中国药理学与毒理学杂志 2016年第10期30卷 1029-1030页

作者： YANG huan cheng Xiao zhang jun YANG Yin-lin WANG Yue-hua du guan-hua Beijing Key Laboratory of Drug Target Identification and Drug Screening Institute of Materia MedicaChinese Academy of Medical Sciences & Peking Union Medical College guangzhou University of Chinese Medicine

OBJECTIVE To investigate the effects of ex-tract of Ramulus Cinnamom(RC)against LPS-induced inflammation in *** Activated microglia releases various pro-inflammatory cytokines to induce neuroinflammation in ***(LPS)is an endotoxin from the outer membrane of Gram-negative bacteria that activates *** assay was used to observe the cell *** content of NO in supernatant was measured by Griess *** levels of IL-1β,IL-6 and TNF-αin supernatant were detected by ELISA *** intracellular COX-2,TLR4,and My D88expression was assayed by Western *** RC extract 30 and 100μg·m L-1significantly decreased the production of related inflammatory factors such as NO(Pduced by LPS in *** RC extract may have therapeutic potential for the improvement of neuroinflammation,and the mechanism may be involved in down-regulation of TLR4/My D88 inflammation pathway.

关键词： Ramulus Cinnamom lipopolysaccharide BV2 cells neuroinflammation

Modeling Soil Water Retention Curve with a Fractal Method

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Pedosphere 2006年第2期16卷 137-146页

作者： huaNG guan-hua zhang ren-duo huaNG Quan-Zhong department of Irrigation and Drainage Chinese-Israeli International Center for Research and Training in Agriculture China Agricultural University Beijing 100083 （China）. department of renewable Resources University of Wyoming Laramie WY 82071-3354 （USA）

Many empirical models have been developed to describe the soil water retention curve (SWRC). In this study, a fractal model for SWRC was derived with a specially constructed Menger sponge to describe the fractal scaling behavior of soil; relationships were established among the fractal dimension of SWRC, the fractal dimension of soil mass, and soil texture; and the model was used to estimate SWRC with the estimated results being compared to experimental data for verification. The derived fractal model was in a power-law form, similar to the Brooks-Corey and Campbell empirical functions. Experimental data of particle size distribution (PSD), texture, and soil water retention for 10 soils collected at different places in China were used to estimate the fractal dimension of SWRC and the mass fractal dimension. The fractal dimension of SWRC and the mass fractal dimension were linearly related. Also, both of the fractal dimensions were dependent on soil texture, i.e., clay and sand contents. Expressions were proposed to quantify the relationships. Based on the relationships, four methods were used to determine the fractal dimension of SWRC and the model was applied to estimate soil water content at a wide range of tension values. The estimated results compared well with the measured data having relative errors less than 10% for over 60% of the measurements. Thus, this model, estimating the fractal dimension using soil textural data, offered an alternative for predicting SWRC.

关键词： fractal dimension soil texture soil water retention curve

Diesel molecular composition and blending modeling based on SUBEM framework

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Petroleum Science 2022年第2期19卷 839-847页

作者： Yue-Ming guan Dong guan cheng zhang Sheng-hua Yuan guang-Qing Cai Lin-Zhou zhang State Key Laboratory of Heavy Oil Processing Petroleum Molecular Engineering Center(PMEC)China University of PetroleumBeijing102249China SINOPEC Dalian Research Institute of Petroleum and Petrochemicals SINOPECDalian116045LiaoningChina

Diesel molecular compositional model has important application for diesel quality prediction,blending,and molecular-level process model *** this paper,different types of diesel molecular compositional and blending models were constructed based on the SU-BEM *** than 1500 representative molecules were selected to form the molecular structure *** probability density functions(PDFs)combination was determined by experimental data and experience.A quadratic optimization strategy combining genetic algorithm with local optimization algorithm was adopted to improve the accuracy of the compositional *** model results show good agreement with the experimental *** diesel blending model was constructed at the molecular-level based on the above diesel compositional *** properties of the blending model accord with the experimental *** is proved that the compositional models and blending model constructed have high accuracy and strong prediction capability,and are applicable to the industrial process.

关键词： Molecular compositional model Molecular blending model SU-BEM Framework Diesel