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    题名 作者 年代 出处 被引量
1TRPV1 activation improves exercise endurance and energy metabolism through PGC-1α upregulation in mice显示文摘Zhidan Luo Liqun Ma Zhigang Zhao Hongbo He Dachun Yang Xiaoli Feng Shuangtao Ma Xiaoping Chen Tianqi Zhu Tingbing Cao Daoyan Liu Bernd Nilius Yu Huang Zhencheng Yan Zhiming Zhu 2012Cell Research2012,22,3:18
2Holocene aeolian stratigraphic sequences in the eastern portion of the desert belt(sand seas and sandy lands) in northern China and their palaeoenvironmental implications显示文摘This paper presents the environmental history and its responses to palaeoclimatic changes since the start of the Holocene in the eastern portion of the desert belt(sand seas and sandy lands) in northern China by comparing the aeolian sandpalaeosol sequences and their palaeoclimatic proxies. The optically stimulated luminescence(OSL) ages of the aeolian sandpalaeosol sedimentary sequences and a series of palaeoenvironmental proxies show that:(1) The large-scale dune landscape currently in the Kubuqi Sand Sea was formed during the Holocene in general;and the palaeosol was generally developed during the period of 4–2 ka, indicating conditions favorable for vegetation growth, soil development, and organic carbon accumulation due to increased precipitation or effective moisture and weakened aeolian activities;the large-scale expansion of dunes in the recent 2 ka is closely linked to human activities. The variable discharge of the Yellow River with diversions for irrigation may have resulted in a more consistent supply of aeolian particles for dune field expansion.(2) The dune landscape of the Hunshandake Sandy Land was likely formed around 12 ka, and before this, the western part of the Hunshandake Sandy Land would have been covered by a single large lake;it was obviously wetter than today in the sandy land during the period of 9.6–3 ka and the palaeosols were developed at the same time. But the aeolian activities have not been completely dormant in this long-lasting wetter epoch;because the Holocene wetter period was likely time-transgressive across the region.(3) The palaeosol of the Hulunbuir Sandy Land began to develop as early as 14.5 ka, probably continuing until the last 2 ka. The palaeosol development of various dune fields in the eastern portion of the desert belt(sand seas and sandy lands) in northern China is spatially heterogeneous, and even the palaeosol development time in different locations within each sandy land is inconsistent. During the middle Holocene(especially the 7.5–3.5 ka), all the sandy lands were stabilized in general and the intensity of aeolian activities was significantly weakened. The number of palaeoenvironmental records in the eastern portion of the desert belt(sand seas and sandy lands) in northern China has increased rapidly in the past decade, but the amount of published data still does not match the vast extent of the dune fields. It does require much more in-depth palaeoenvironmental studies for a full understanding of the relationship between aeolian activities and climate change in northern China.Xiaoping YANG Peng LIANG Deguo ZHANG Hongwei LI Patrick RIOUAL Xulong WANG Bing XU Zhibang MA Qianqian LIU Xiaozong REN Fangen HU Yuxin HE Gang RAO Ninghua CHEN 2019Science China Earth Sciences2019,62,8:10
3Combining sap flow measurement-based canopy stomatal conductance and ^(13)C discrimination to estimate forest carbon assimilation显示文摘The available methods for studying C uptake of forest and their problems in practices are reviewed, and a new approach to combining sap flow and 13C techniques is proposed in this paper. This approach, obtained through strict mathematic derivation, combines sap flow measure-ment-based canopy stomatal conductance and 13C discrimi-nation to estimate instantaneous carbon assimilation rate of a forest. Namely the mean canopy stomatal conductance (gc) acquired from accurate measurement of sap flux density is integrated with the relationship between 13C discrimination (?) and Ci/Ca (intercellular/ambient CO2 concentrations) and with that between Anet (net photosynthetic rate) and gCO2 (stomatal conductance for CO2) so that a new relation be-tween forest C uptake and ? as well as gc is established. It is a new method of such kind for studying the C exchange be-tween forest and atmosphere based on experimental ecology.ZHAO Ping LU Ping MA Ling SUN Guchou RAO Xingquan CAI Xi'an ZENG Xiaoping 2005Chinese Science Bulletin2005,50,18:9
4Status and development of high-power laser facilities at the NLHPLP显示文摘In this paper, we review the status of the multifunctional experimental platform at the National Laboratory of High Power Laser and Physics(NLHPLP). The platform, including the SG-II laser facility, SG-II 9th beam, SG-II upgrade(SG-II UP) facility, and SG-II 5 PW facility, is operational and available for interested scientists studying inertial confinement fusion(ICF) and a broad range of high-energy-density physics. These facilities can provide important experimental capabilities by combining different pulse widths of nanosecond, picosecond, and femtosecond scales. In addition, the SG-II UP facility, consisting of a single petawatt system and an eight-beam nanosecond system, is introduced including several laser technologies that have been developed to ensure the performance of the facility. Recent developments of the SG-II 5 PW facility are also presented.Jianqiang Zhu Jian Zhu Xuechun Li Baoqiang Zhu Weixin Ma Xingqiang Lu Wei Fan Zhigang Liu Shenlei Zhou Guang Xu Guowen Zhang Xinglong Xie Lin Yang Jiangfeng Wang Xiaoping Ouyang Li Wang Dawei Li Pengqian Yang Quantang Fan Mingying Sun Chong Liu Dean Liu Yanli Zhang Hua Tao Meizhi Sun Ping Zhu Bingyan Wang Zhaoyang Jiao Lei Ren Daizhong Liu Xiang Jiao Hongbiao Huang Zunqi Lin 2018High Power Laser Science and Engineering2018,6,4:8
5Alleviation of mycotoxin biodegradation agent on zearalenone and deoxynivalenol toxicosis in immature gilts显示文摘Background: The current study was carried out to evaluate the effects of mycotoxin biodegradation agent(MBA, composed of Bacillus subtilis ANSB01 G and Devosia sp. ANSB714) on relieving zearalenone(ZEA) and deoxynivalenol(DON) toxicosis in immature gilts.Methods: A total of forty pre-pubertal female gilts(61.42 ± 1.18 kg) were randomly allocated to four diet treatments: CO(positive control); MO(negative control, ZEA 596.86 μg/kg feed and DON 796 μg/kg feed);COA(CO + 2 g MBA/kg feed); MOA(MO + 2 g MBA/kg feed). Each treatment contained 10 replicates with 1 gilt per replicate. Gilts were housed in an environmentally controlled room with the partially slatted floor.Results: During the entire experimental period of 28 d, average daily gain(ADG) and average daily feed intake(ADFI)of gilts in MO group was significantly reduced compared with those in CO group. The vulva size of gilts was significantly higher in MO group than CO group. In addition, significant increases in the plasma levels of Ig A,Ig G, IL-8, IL-10 and PRL were determined in MO group compared with that in CO group. ZEA and DON in the diet upregulated apoptotic caspase-3 in ovaries and uteri, along with down-regulated the anti-apoptotic protein Bcl-2 in ovaries. The supplementation of MBA into diets co-contaminated with ZEA and DON significantly increased ADG, decreased the vulva sizes, reduced the levels of Ig G, IL-8 and PRL in plasma, and regulated apoptosis in ovaries and uteri of gilts.Conclusions: The present results indicated that feeding diet contaminated with ZEA and DON simultaneously(596.86 μg/kg + 796 μg/kg) had detrimental effects on growth performance, plasma immune function and reproductive status of gilts. And MBA could reduce the negative impacts of these two toxins, believed as a promising feed additive for mitigating toxicosis of ZEA and DON at low levels in gilts.Donghui Shi Jianchuan Zhou Lihong Zhao Xiaoping Rong Yu Fan Humera Hamid Wenqiang Li Cheng Ji Qiugang Ma 2018Journal of Animal Science and Biotechnology2018,9,3:7
6IL-17 sustains the plasma cell response via p38-mediated Bcl-xL RNA stability in lupus pathogenesis显示文摘Recent studies have demonstrated a central role for plasma cells in the development of autoimmune diseases,such as systemic lupus erythematosus(SLE).Currently,both the phenotypic features and functional regulation of autoreactive plasma cells during SLE pathogenesis remain largely unclear.In this study,we first found that a major subset of IL-17 receptor-expressing plasma cells potently produced anti-dsDNA IgG upon IL-17A(IL-17)stimulation in SLE patients and lupus mice.Using a humanized lupus mouse model,we showed that the transfer of Th17 cell-depleted PBMCs from lupus patients resulted in a significantly reduced plasma cell response and attenuated renal damage in recipient mice compared to the transfer of total SLE PBMCs.Moreover,long-term BrdU incorporation in lupus mice detected highly enriched long-lived BrdU+subsets among IL-17 receptor-expressing plasma cells.Lupus mice deficient in IL-17 or IL-17 receptor C(IL-17RC)exhibited a diminished plasma cell response and reduced autoantibody production with attenuated renal damage,while the adoptive transfer of Th17 cells triggered the plasma cell response and renal damage in IL-17-deficient lupus mice.In reconstituted chimeric mice,IL-17RC deficiency resulted in severely impaired plasma cell generation but showed no obvious effect on germinal center B cells.Further mechanistic studies revealed that IL-17 significantly promoted plasma cell survival via p38-mediated Bcl-xL transcript stabilization.Together,our findings identified a novel function of IL-17 in enhancing plasma cell survival for autoantibody production in lupus pathogenesis,which may provide new therapeutic strategies for the treatment of SLE.Kongyang Ma Wenhan Du Fan Xiao Man Han Enyu Huang Na Peng Yuan Tang Chong Deng Lixiong Liu Yulan Chen Jingjing Li Shiwen Yuan Qin Huang Xiaoping Hong Dajun Hu Xiaoyan Cai Quan Jiang Dongzhou Liu Liwei Lu 2021Cellular & Molecular Immunology2021,18,7:6
7Analysis of the ore-controlling structure of the Shihu gold deposit, Hebei Province and deep-seated ore-prospecting prediction显示文摘Under the guidance of the theory of mantle-branch structure-associated metallogenesis and on the basis of the geological characteristics, analysis of the ore-forming and ore-controlling structures, the geochemical characteristics of metallogenesis, the source of ore-forming materials, changes in the physical and chemical conditions of metallogenesis, changes in the vertical width of ore veins, and changes in gold grade of the Shihu gold deposit, the mechanism of its metallogenesis was discussed and the rules of vertical variation of ore veins were summarized in this study. It is pointed out that the orebodies under exploitation at present time should be in the middle and upper portions of gold veins in the Shihu gold mining district. Particularly on the basis of the characteristics of mantle-branch structure-associated metallogenesis, it is indicated that metallogenesis is controlled mainly by such ore-forming conditions as temperature and pressure. Deep-seated ore-forming fluids are characterized mainly by injection and precipitation. So the vein bodies in the adjacent metallogenic structures are of obvious comparability, and there would be great prospects for ore search both at depth and in the periphery of the Shihu gold deposit. Therefore, ore prospecting should be strengthened both at depth and in the peripheries.NIU Shuyin WANG Baode SUN Aiqun CHEN Chao WANG Zili MA Baojun WANG Wenxue JIANG Xiaoping ZHAO Yongli GAO Yincang LIU Huabin QIU Jianping 2009Chinese Journal Of Geochemistry2009,28,4:6
8Fe5C2 nanoparticles as low-cost HER electrocatalyst:the importance of Co substitution显示文摘Constructing and understanding the doping effect of secondary metal in transition metal carbide(TMC)catalysts is pivotal for the design of low-cost hydrogen evolution reaction(HER) electrocatalysts. In this work, we developed a wet-chemistry strategy for synthesizing Co-modified Fe_5C_2 nanoparticles((Fe_(1-x)Cox)_5C_2 NPs) as highly active HER electrocatalysts in basic solution. The structure of(Fe_(1-x)Cox)_5C_2 NPs was characterized by X-ray diffraction(XRD), extended X-ray absorption fine structure spectra(EXAFS) and scanning/transmission electron microscopy(S/TEM), indicating that the isomorphous substitution of cobalt in the lattice of Fe_5C_2.(Fe_(0.75) Co_(0.25))_5C_2 exhibited the best HER activity(174 mV for j = -10 mA/cm^2). Computational calculation results indicate that Co provides the most active site for HER. X-ray adsorption spectra(XAS) studies further suggested that the electron transfer in Fe–C bonds are enhanced by the substitution of Co, which modulates the hydrogen adsorption on the adjacent electronic-enriched carbon, and therefore promotes HER activity. Our results affirm the design of lowcost bimetallic TMCs based HER catalysts.Siwei Li Pengju Ren Ce Yang Xi Liu Zhen Yin Weizhen Li Hanjun Yang Jian Li Xiaoping Wang Yi Wang Ruochen Cao Lili Lin Siyu Yao Xiaodong Wen Ding Ma 2018Science Bulletin2018,63,20:6
9Clinical Characteristics of Hospitalized Patients with SARS-CoV-2 and Hepatitis B Virus Co-infection显示文摘Dear Editor,Coronavirus disease 2019(COVID-19)is a global pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-Co V-2).SARS-Co V-2 infection was first detected in Wuhan,China in late December 2019.The virus was spreading rapidly to other cities of China and accumulating cases had been reported(Li et al.2020).Xiaoping Chen Qunqun Jiang Zhiyong Ma Jiaxin Ling Wenjia Hu Qian Cao Pingzheng Mo Lei Yao Rongrong Yang Shicheng Gao Xien Gui Wei Hou Yong Xiong Jinlin Li Yongxi Zhang 2020Virologica Sinica2020,35,6:6
10Mining geographic episode association patterns of abnormal events in global earth science data显示文摘Abnormal events in earth science have great influence on both the natural envi-ronment and the human society. Finding association patterns among these events has great significance. Because data in earth science has characteristics of mass,high dimension,spatial autocorrelation and time delay,existing mining technolo-gies cannot be directly used on it. We propose a RSNN (range-based searching nearest neighbors) spatial clustering algorithm to reduce the data size and auto-correlation. Based on the clustered data,we propose a GEAM (geographic episode association pattern mining) algorithm which can deal with events time lags and find interesting patterns with specific constraints,to mine the association patterns. We carried out experiments on global climate datasets and found many interesting association patterns. Some of the patterns are coincident with known knowledge in climate science,which indicates the correctness and feasibilities of our methods,and the others are unknown to us before,which will give new information to this research field.WU TianShu,SONG GuoJie,MA XiuJun,XIE KunQing,GAO XiaoPing & JIN XingXing Key Laboratory of Machine Perception,Ministry of Education,and Department of Machine Intelligence,Peking University,Beijing 100871,China 2008Science China(Technological Sciences)2008,51,S1:5
11Protective effect of oxysophoridine on cerebral ischemia/reperfusion injury in mice显示文摘Oxysophoridine, a new alkaloid extracted from Sophora alopecuroides L., has been shown to have a protective effect against ischemic brain damage. In this study, a focal cerebral ischemia/reperfusion injury model was established using middle cerebral artery occlusion in mice. Both 62.5, 125, and 250 mg/kg oxysophoridine, via intraperitoneal injection, and 6 mg/kg nimodipine, via intragastric administration, were administered daily for 7 days before modeling. After 24 hours of reperfusion, mice were tested for neurological deficit, cerebral infarct size was assessed and brain tissue was collected. Results showed that oxysophoridine at 125, 250 mg/kg and 6 mg/kg nimodipine could reduce neurological deficit scores, cerebral infarct size and brain water content in mice. These results provided evidence that oxysophoridine plays a protective role in cerebral ischemia/reperfusion injury. In addition, oxysophoridine at 62.5, 125, and 250 mg/kg and 6 mg/kg nimodipine increased adenosine-triphosphate content, and decreased malondialdehyde and nitric oxide content. These compounds enhanced the activities of glutathione-peroxidase, superoxide dismutase, catalase, and lactate dehydrogenase, and decreased the activity of nitric oxide synthase. Protein and mRNA expression levels of N-methyl-D-aspartate receptor subunit NR1 were markedly inhibited in the presence of 250 mg/kg oxysophoridine and 6 mg/kg nimodipine. Our experimental findings indicated that oxysophoridine has a neuroprotective effect against cerebral ischemia/reperfusion injury in mice, and that the effect may be due to its ability to inhibit oxidative stress and expression of the N-methyl-D-aspartate receptor subunit NR1.Hongbo Wang Yuxiang Li Ning Jiang Xiaoping Chen Yi Zhang Kuai Zhang Tengfei Wang Yinju Hao Lin Ma Chengjun Zhao Yanrong Wang Tao Sun Jianqiang Yu 2013Neural Regeneration Research2013,8,15:5
12Application study on complex wetting agent for dust-proof after gas drainage by outburst seams in coal mines显示文摘After gas drainage,the outburst seam is dry and,consequently,during subsequent mechanized mining,unwanted dust production is extensive.Because the hard dustfall typically has a small particle size it contains a high percentage of respirable dust.Considering these factors,this paper improved the efficiency of dustfall by reducing the surface tension of the liquid used as a wetting agent,then configuring five kinds of wetting agents by adopting various doses and types of surfactants,neutral inorganic salts and chemical additives,etc.After purchasing DA-85 and SRJ-1 wetting agent,the surface tension and critical micelle concentration of seven kinds of wetting agents were measured using the capillary rise method.Wetting agent A was confirmed to have the best comprehensive effect.The experiments were optimized by measuring and comparatively analyzing contact angles of pure water,SRJ-1 wetting agent and wetting agent A on the surface of different coal samples using a contact angle measurement instrument(HARKESPCA).By comparative analysis,dust-proof effects of seam,dynamic pressure water infusion and highpressure spray in the tunneling face at the Daning coal mine using pure water,wetting agent SRJ-1and A,it was determined that after using wetting agent A,the average dust concentration in the place of the mining machine driver,10 m and 110 m away from the tunneling front is approximately 300 mg/m^3,240 mg/m^3 and 100 mg/m^3,respectively.This practice increased the dust-proof efficiency dramatically and achieved a good comprehensive dust-proof effect.Wang Kai Ma Xiaoping Jiang Shuguang Wu Zhengyan Shao Hao Pei Xiaodong 2016International Journal of Mining Science and Technology2016,26,4:5
13Review of lithium-ion battery state of charge estimation显示文摘The technology deployed for lithium-ion battery state of charge(SOC)estimation is an important part of the design of electric vehicle battery management systems.Accurate SOC estimation can forestall excessive charging and discharging of lithium-ion batteries,thereby improving discharge efficiency and extending cycle life.In this study,the key lithium-ion battery SOC estimation technologies are summarized.First,the research status of lithium-ion battery modeling is introduced.Second,the main technologies and difficulties in model parameter identification for lithium-ion batteries are discussed.Third,the development status and advantages and disadvantages of SOC estimation methods are summarized.Finally,the current research problems and prospects for development trends are summarized.Ning Li Yu Zhang Fuxing He Longhui Zhu Xiaoping Zhang Yong Ma Shuning Wang 2021Global Energy Interconnection2021,4,6:5
14AFM quantitative analysis and determination of shear angle of {259}_f martensitic surface relief显示文摘An attentive observation and quantitative analysis of {259}f martensitic surface relief in an Fe-23Ni-0.55C alloy are made by means of an atomic force microscope (AFM), and different martensitic variants' shear angles are determined in this paper. The experiments show that {259}f martensitic surface relief exhibits regular shape in many cases, which is in agreement with the prediction of invariant plane strain (IPS). Generally, {259}f martensitic surface relief appears to be 'N'-shaped, but it is tent-shaped in the case of zigzag-shaped martensite. The compressed deformation of parent phase diminishes the surface relief in size but with little change of its relief angle. {259}f martensitic surface relief, large or small, has approximately the same relief angles, exhibiting a good 'self-similar fractal'. The determined values of different {259}f martensitic variants' shear angles are in fine agreement with the prediction of Wechsler-Liberman-Read (W-L-R) theory, with only a slight difference of less than 3.65°.LIN Xiaoping, GU Nanju, ZHANG Yong, MENG Zhaowei and MA Xiaoli(Department of Materials Science and Technology, Hebei University of Technology, Tianjin 300130, China) 2002Progress in Natural Science:Materials International2002,12,10:5
15Sphingosine-1-phosphate (S1P) mediates darkness-induced stomatal closure through raising cytosol pH and hydrogen peroxide (H_2O_2) levels in guard cells in Vicia faba显示文摘The role and signaling of sphingosine-1-phosphate (S1P) during darkness-induced stomatal closure were examined in Vicia faba. Darkness substantially raised S1P and hydrogen peroxide (H 2 O 2 ) levels and closed stomata. These darkness effects were significantly suppressed by DL-threo-dihydrosphingosine (DL-threo-DHS) and N,N-dimethylsphingosine (DMS), two inhibitors of long-chain base kinases. Exogenous S1P led to stomatal closure and H 2 O 2 production, and the effects of S1P were largely prevented by the H 2 O 2 modulators ascorbic acid, catalase, and diphenyleneiodonium. These results indicated that S1P mediated darkness-induced stomatal closure by triggering H 2 O 2 production. In addition, DL-threo-DHS and DMS significantly suppressed both darkness-induced cytosolic alkalization in guard cells and stomatal closure. Exogenous S1P caused cytosolic alkalization and stomatal closure, which could be largely abolished by butyric acid. These results demonstrated that S1P syn-thesis was necessary for cytosolic alkalization during stomatal closure caused by darkness. Furthermore, together with the data described above, inhibition of darkness-induced H 2 O 2 production by butyric acid revealed that S1P synthesis-induced cytosolic alkalization was a prerequisite for H 2 O 2 production during stomatal closure caused by darkness, a conclusion supported by the facts that the pH increase caused by exogenous S1P had a shorter lag and peaked faster than H 2 O 2 levels and that butyric acid prevented exogenous S1P-induced H 2 O 2 production. Altogether, our data suggested that darkness induced S1P synthesis, causing cytosolic alkalization and subsequent H 2 O 2 production, finally leading to stomatal closure.MA YinLi SHE XiaoPing YANG ShuShen 2012Science China(Life Sciences)2012,55,11:4
16Fargeted elimination of mutant mitochondria DNA in MELAS-iPSCs by mitoTALENs显示文摘Yi Yang Han Wu Xiangjin Kang Yanhui Liang Ting Lan Tianjie Li Tao Tan Jiangyun Peng Quanjun Zhang Geng An Yali Liu Qian Yu Zhenglai Ma Ying Lian Boon Seng Soh Qingfeng Chen Ping Liu Yaoyong Chen Xiaofang Sun Rong Li Xiumei Zhen Yang Yu Xiaoping Li Yong Fan 2018Protein & Cell2018,9,3:4
17Mild Breakthrough Infection in a Healthcare Professional Working in the Isolation Area of a Hospital Designated for Treating COVID-19 Patients—Shaanxi Province,China,March,2021显示文摘Summary What is already known about this topic?Healthcare workers are at high risk of acquiring COVID-19 from occupational exposure to COVID-19 virus during their daily medical service work.Excellent infection prevention and control measures and adequate personal protective equipment(PPE)are essential to reduce the risk of hospital-acquired COVID-19.Chaofeng Ma Songtao Xu Yecheng Yao Pengbo Yu You Xu Rui Wu Hailong Chen Xiaoping Dong 2021China CDC weekly2021,3,19:4
18Formation mechanism of shrinkage and large inclusions of a 70t 12Cr2Mo1 heavy steel ingot显示文摘Shrinkage cavities and large inclusions are serious internal defects of heavy steel ingot and influence the quality of subsequent forgings. In order to remove these two types of defects, a 70 t 12Cr2Mo1 heavy ingot fabricated by vacuum carbon de-oxidation process was sectioned and investigated by means of structure observation and EDS analysis. To further study the forming mechanism of shrinkage and inclusion defects and find possible solutions, simulation on pouring and solidification processes was also carried out using Fluent and ProCAST software, respectively. Results show that the shrinkage defects do not appear in the middle-upper part of the ingot. The critical value of shrinkage cavity criterion is ascertained as 0.013 on the basis of sectioning investigation and simulation results, which can be used in computer simulation to predict and avoid shrinkage defects in production of 12Cr2Mo1 ingots with different weights. However, large inclusions are found at the bottom of the ingot body. The bad thermal conditions of the ingot surface and large amount of entrained slag are the main origin of the large inclusions. The simulation result of the pouring process shows that large inclusions may be eliminated by combined measures of improving the top thermal condition and controlling the height of rudimental molten steel in the ladle to above 300 mm.Liu Hongwei Fu Paixian Kang Xiuhong Ma Xiaoping 2014China Foundry2014,11,1:4
19Selective catalytic hydrogenation of naphthalene to tetralin over a NiMo/Al2O3 catalyst显示文摘The selective catalytic hydrogenation of naphthalene to high-value tetralin was systematically investigated.A series of Al2O3 catalysts containing different active metals(Co,Mo,Ni,W)were prepared by incipient wetness impregnation.The effects of different active metals forms(oxidation,reduction,sulfuration)and reaction conditions on naphthalene hydrogenation were investigated and the catalysts were characterized by XRD,XPS,BET,NH3-TPD and SEM.Especially,Ni-Mo/Al2O3 was first used in this reactive system.The results show that the oxidative4%Ni O-20%MoO3/Al2O3 is the best catalyst for the preparation of tetralin.The conversion of naphthalene and the selectivity of tetralin can reach 95.62%and 99.75%respectively at 200℃,8 h and 6 MPa.Compared with reduced and sulfureted 4%Ni O-20%MoO3/Al2O3 catalysts,oxidative 4%Ni O-20%MoO3/Al2O3 has a well dispersed and uniform monolayer of the active metals,larger pore volume and size,and larger total acidity.NiO-MoO3/Al2O3 has a synergistic effect between NiO activity and MoO3 selectivity.Xiaoping Su Pu An Junwen Gao RuchengWang Yujuan Zhang Xi Li Yangkun Zhao Yongqi Liu Xiaoxun Ma Ming Sun 2020Chinese Journal of Chemical Engineering2020,28,10:4
20Estrogenic effect of the extract of Renshen(Radix Ginseng) on reproductive tissues in immature mice显示文摘OBJECTIVE: To evaluate the estrogenic efficacy of Renshen(Radix Ginseng)(GS) on reproductive target tissues in immature mice.METHODS: One hundred and ten female immature Kunming(KM) mice, 21-day-old, were randomly assigned to eleven groups, 10 for each; one served as control group treated with 0.154 mg/kg estradiol valerate(EV,n = 10), the rest were treated respectively with GS intragastrically at a daily dose of 0.5,1.0, 1.5, 3.0, 6.0, 12.0, 18.0, 24.0 and 30.0 g/kg(n =10 in per group) for 7 days. The estrous cycle, uterine weight, hormone levels in circulation and histomorphology changes of uterus and vagina were scrupulously examined. The estrogen receptor(ER)α and ERβ expressions in the uterus and vagina were detected by immunohistochemistry and western blotting.RESULTS: Treatment with GS at the dose of 12.0,18.0 and 24.0 g/kg resulted significant estrogenic activity in the mice, as indicated by advanced and prolonged estrous stage and increased uterine weight(all P < 0.05). GS treatment substantially promoted development of reproductive tissue by thickening the uterine endometrium and increasing vaginal epithelial layers. In addition, treatment with GS induced significant up-regulation of ERαand ERβ expressions in reproductive tissues, and ERα up-regulation was stronger than that of ERβ.GS could raise levels of circulating estrogen, simultaneously decrease levels of luteinizing hormone and follicle-stimulating hormone(all P < 0.001)compared with the control group.CONCLUSION: Our findings suggest that GS had estrogenic effect on reproductive tissues in immature mice by stimulating biosynthesis of estrogen in circulation and up-regulating ERs.Ding Jie Xu Ying Ma Xiaoping An Jinna Yang Xiudong Liu Zhiqiang Lin Na 2015Journal of Traditional Chinese Medicine2015,35,4:3
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