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Nano Research 2020年第11期13卷 3019-3024页

作者： Fei hui Chong Li yanhui Chen Chunhui Wang Jingping huang ang Li Wei Li Jin Zou xiaodong han Key Lab of Microstructure and Property of Advanced Materials Beijing University of TechnologyBeijing100124China International Laboratory for Quantum Functional Materials of henan School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou450001China School of Mechanical and Mining Engineering and Centre for Microscopy and Microanalysis The University of QueenslandSt LuciaQLD4072Australia

hydrogen energy is a resuscitated clean energy source and its sensitive detection in air is crucial due to its very low explosive *** oxide decorated with noble metal nanoparticles has been used for the enhancement of gas detection and exhibits superior *** the intrinsic mechanism of the detection and the enhancement mechanism is thus becoming a fundamental issue for the further development of novel metal/oxide compound gas-sensing ***,the correlation between the microstructural evolution,the charge transport and the complex sensing process has not yet been directly revealed and its atomic mechanism is still *** this study,an Au/WO_(2.7) compound was synthesized and exhibited a strongly enhanced gas sensitivity to many reductive gases,especially ***-corrected environmental transmission electron microscopy was used to investigate the atomic-scale microstructural evolution in situ during the reaction between h_(2) and Au/WO_(2.7) *** and sintering processes of the Au particles on the WO_(2.7) surface were observed under heating and gaseous environments,and no injection of hydrogen atoms was *** principle calculations verified the swing and sintering processes,and they can be explained by the enhancement of h2 sensitivity.

关键词： in situ environmental TEM h2 sensing Au/WO_(2.7) gas-solid interface

Monitoring of edema progression in permanent and transient MCAO model using SS-OCT

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Journal of Innovative Optical health Sciences 2021年第1期4卷 63-71页

作者： yao yu Ziyue Meng ang Li yang Lin Jian Liu yushu Ma yi Wang Zhenhe Ma School of Control Engineering Northeastern University at Qinhuangdao Qinhuangdao 066004P.R.China School of Computer Science and Engineering Northeastern University Shenyang 110169P.R.China

Cerebral edema is a severe complication of acute ischemic stroke with high mortality but limited *** parameters such as brain water content and intracranial pressure may represent the global assessment of edema,optical properties can appear heterogeneously throughout the cerebral tissue relative to the site of *** this study,we have monitored the edema formation and progression in both permanent and transient middle cerebral artery oc-clusion models in *** was reflected by the decrease of optical attenuation coefficient(OAC)value in OCT *** utilizing swept-source optical coherence tomography(SS-OCT),we found that in photochemically induced permanent focal stroke model,both the edema size and edema index,steadily developed until the end of monitor(7 h).Comparatively,when transient ischemia was introduced with endothelin-1(ET-1),the edema was detected as early as 15 min,and began to recover after 30 min until monitor was finished(3 h).Despite the majority of the edema being recovered to some extent,the condition of a small region within the edema kept deteriorating,presumably due to the reperfusion damage which might result in serious clinical *** study has compared the edema characteristics from two different acute ischemic stroke *** work not only confirms the capability of OCT to temporal and spatial monitor of edema but is also able to locate focal conditions at some areas that might highly determine the prognosis and treatment decisions.

关键词： Swept-source optical coherence tomography ischemic stroke cerebral edema optical attenuation coefficient middle cerebral artery occlusion

New Measurements for ^(8)he Excited States

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Chinese Physics Letters 2012年第8期29卷 69-72页

作者： xIAO Jun yE yan-Lin CAO Zhong-xin JIang Dong-xing ZhENG Tao hUA hui LI Zhi-huan LI xiang-Qing GE yu-Cheng LOU Jian-Ling Pang Dan-yang LV Lin-hui LI Qi-Te QIAO Rui yOU hai-Bo ChEN Rui-Jiu h.Sakurai h.Otsu M.Nishimura S.Sakaguchi h.Baba y.Togano K.yoneda LI Chen Wang Shuo Wang he LI Kuo-ang y.Nakayama y.Kondo S.Deguchi y.Satou K.h.Tshoo School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871 RIKEN 2-1HirosawaWakoSaitama 351-0198Japan Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 Department of Physics Tokyo Institute of TechnologyJapan School of Physics Seoul National UniversityKorea

Breakup reactions of the double borromean nucleus ^(8)he were measured at 82.3 MeV/u on Ch2 and C *** coincident detection of two decaying neutrons and the high performance for neutron cross talk rejection are realized in this *** relative energy spectrum for ^(8)he was reconstructed with good *** spectrum exhibits a structure of two resonant peaks,one at an excitation energy of about 3.0 and the other at about 4.14 MeV,*** larger cross section for the first resonance is observed in comparison to the results reported previously.

关键词： experiment MeV/u spectrum

Identification of Fucans from Four Species of Sea Cucumber by high Temperature ~1h NMR

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Journal of Ocean University of China 2014年第5期13卷 871-876页

作者： WU Nian ChEN Shiguo yE xingqian LI Guoyun yIN Li'ang xUE Changhu College of Biosystem Engineering and Food Science Zhejiang University College of Food Science and Engineering Ocean University of China

Acidic polysaccharide, which has various biological activities, is one of the most important components of sea cucumber. In the present study, crude polysaccharide was extracted from four species of sea cucumber from three different geographical zones, Pearsonothuria graeffei(Pg) from Indo-Pacific, holothuria vagabunda(hv) from Norwegian Coast, Stichopus tremulu(St) from Western Indian Ocean, and Isostichopus badionotu(Ib) from Western Atlantic. The polysaccharide extract was separated and purified with a cellulose DEAE anion-exchange column to obtain corresponding sea cucumber fucans(SC-Fucs). The chemical property of these SC-Fucs, including molecular weight, monosaccharide composition and sulfate content, was determined. Their structure was compared simply with fourier infrared spectrum analyzer and identified with high temperature 1h nuclear magnetic resonance spectrum analyzer(NMR) and room temperature 13 C NMR. The results indicated that Fuc-Pg obtained from the torrid zone mainly contained 2,4-O-disulfated and non-sulfated fucose residue, whereas Fuc-Ib from the temperate zone contained non-, 2-O- and 2,4-O-disulfated fucose residue; Fuc-St from the frigid zone and Fuc-hv from the torrid zone contained mainly non-sulfated fucose residue. The proton of SC-Fucs was better resolved via high temperature 1h NMR than via room temperature 1h NMR. The fingerprint of sea cucumber in different sea regions was established based on the index of anomer hydrogen signal in SC-Fucs. Further work will help to understand whether there exists a close relationship between the geographical area of sea cucumber and the sulfation pattern of SC-Fucs.

关键词： sea cucumber sulfated fucan composition analysis 1h NMR identification

Efficacy of chitosan and sodium alginate scaffolds for repair of spinal cord injury in rats

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Neural Regeneration Research 2018年第3期13卷 502-509页

作者： Zi-ang yao Feng-jia Chen hong-li Cui Tong Lin Na Guo hai-ge Wu School of Life Science and Technology Dalian University

Spinal cord injury results in the loss of motor and sensory pathways and spontaneous regeneration of adult mammalian spinal cord neurons is limited. Chitosan and sodium alginate have good biocompatibility, biodegradability, and are suitable to assist the recovery of damaged tissues, such as skin, bone and nerve. Chitosan scaffolds, sodium alginate scaffolds and chitosan-sodium alginate scaffolds were separately transplanted into rats with spinal cord hemisection. Basso-Beattie-Bresnahan locomotor rating scale scores and electrophysiological results showed that chitosan scaffolds promoted recovery of locomotor capacity and nerve transduction of the experimental *** days after surgery, chitosan scaffolds retained the original shape of the spinal cord. Compared with sodium alginate scaffolds- and chitosan-sodium alginate scaffolds-transplanted rats, more neurofilament-h-immunoreactive cells （regenerating nerve fibers） and less glial fibrillary acidic protein-immunoreactive cells （astrocytic scar tissue） were observed at the injury site of experimental rats in chitosan scaffold-transplanted rats. Due to the fast degradation rate of sodium alginate, sodium alginate scaffolds and composite material scaffolds did not have a supporting and bridging effect on the damaged tissue. Above all, compared with sodium alginate and composite material scaffolds, chitosan had better biocompatibility, could promote the regeneration of nerve fibers and prevent the formation of scar tissue,and as such, is more suitable to help the repair of spinal cord injury.

关键词： nerve regeneration spinal cord injury chitosan sodium alginate functional recovery scaffold neurofilament-h glial fibrillary acidic protein scar tissue locomotor capacity neural regeneration

Changes in intestinal mucosal immune barrier in rats with endotoxemia

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World Journal of Gastroenterology 2009年第46期15卷 5843-5850页

作者： Chong Liu ang Li yi-Bing Weng Mei-Li Duan Bao-En Wang Shu-Wen Zhang Departmentof Critical Care Medicine Beijing Friendship Hospital Affiliatedto Capital Medical University Beijing 100050 China Liver Research Center Beijing FriendshipHospital Affiliated to Capital Medical University Beijing100050 China Department of Infectious Disease andCritical Care Medicine Beijing Friendship Hospital Affiliatedto Capital Medical University Beijing 100050 China

AIM： To investigate the dysfunction of the immunological barrier of the intestinal mucosa during endotoxemia and to elucidate the potential mechanism of this dysfunction. METhODS： Male Wistar rats were randomly distributed into two groups： control group and lipopolysaccharide （LPS） group. Endotoxemia was induced by a single caudal venous injection of LPS. Animals were sacrificed in batches 2, 6, 12 and 24 h after LPS infusion. The number of microfold （M）-cells, dendritic cells （DCs）, CD4＋ T cells, CD8＋ T cells, regulatory T （Tr） cells and IgA＋ B cells in the intestinal mucosa were counted after immunohistochemical staining. Apoptotic lymphocytes were counted after TUNEL staining. The levels of interleukin （IL）-4, interferon （IFN）-γ, and forkhead box P3 （Foxp3） in mucosal homogenates were measured by ELISA. The secretory IgA （sIgA） content in the total protein of one milligram of small intestinal mucus was detected using a radioimmunological ***： This research demonstrated that LPS-induced endotoxemia results in small intestinal mucosa injury. The number of M-cells, DCs, CD8~ T cells, and IgA~ B cells were decreased while Tr cell and apoptotic lymphocyte numbers were increased significantly. The number of CD4＋ T cells increased in the early stages and then slightly decreased by 24 h. The level of IL-4 significantly increased in the early stages and then reversed by the end of the study period. The level of IFN-T increased slightly in the early stages and then decreased markedly by the 24 h time point. Level of Foxp3 increased whereas sIgA level ***： Mucosal immune dysfunction forms part of the intestinal barrier injury during endotoxemia. The increased number and function of Tr cells as well as lymphocyte apoptosis result in mucosal immunode- ficiency.

关键词： Endotoxemia Rats Intestinal mucosa Immunity

hZSM-5 的低温水热改性及其己烯芳构化性能

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石化技术与应用 2024年第3期42卷 165-170页

作者：魏永峰李剑程子昂杨丽娜辽宁石油化工大学石油化工学院辽宁抚顺113001 中海油田服务股份有限公司天津300450

对hZSM-5在70,100和150℃下进行低温水热改性,分别制得催化剂T 70-hZ-5,T 100-hZ-5和T 150-hZ-5,利用x射线衍射仪、x射线荧光光谱仪、物理吸附仪、化学吸附分析仪和红外光谱仪等对上述催化剂进行表征,并对其己烯芳构化催化性能进行了评... 详细信息

对hZSM-5在70,100和150℃下进行低温水热改性,分别制得催化剂T 70-hZ-5,T 100-hZ-5和T 150-hZ-5,利用x射线衍射仪、x射线荧光光谱仪、物理吸附仪、化学吸附分析仪和红外光谱仪等对上述催化剂进行表征,并对其己烯芳构化催化性能进行了评价。结果表明:低温水热改性保持了hZSM-5的完整晶相结构,提高了其硅铝比[n(Si)/n(Al)],B酸和L酸酸量比(B/L)及平均孔径;酸量的降低和孔径的增大有利于hZSM-5寿命的延长,B/L值的增大有利于选择性的提高;在反应温度405℃,反应压力0.2 MPa,质量空速2 h-1的条件下,T 100-hZ-5的催化寿命可达44 h,比改性前延长了36 h;当反应8 h时,hZSM-5的苯、甲苯和二甲苯混合物(BTx)选择性已迅速降到35%左右,而T 100-hZ-5的仍接近55%。

关键词： hZSM-5 低温水热改性孔结构烯烃己烯芳构化催化剂寿命选择性

Conformation Analysis and Thermodynamics of Binding Behavior of DABCO to p/p type Dimeric Porphyrin hosts

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Chinese Chemical Letters 2000年第11期11卷 981-984页

作者： Qi Zhi REN Zhi ang ZhU Jin Wang hUang Liang Nian JI yong Ti ChEN Nankai University Department of ChemistryTianjin 300071 Zhongshan University School of Chemistry and Chemical EngineeringGuangzhou 510275

The binding conformations of bidentate ligand DABCO(1,4-diazobicyclo [2,2,2]octane) to a series of p'p type zinc porphyrin dimers covalently linked with flexible alkoxy chain - O(Ch2)(n)O- (n=2-10) are described by h-1 NMR and UV-vis spectroscopy. DABCO can bind inside the cavities of porphyrin dimers and form a ternary sandwich complex as the alkoxy chain length is long enough. The thermodynamic parameters which control the binding behavior are investigated.

关键词： zinc porphyrin dimer DABCO thermodynamic parameters binding conformation

胶东盘子涧金矿床成矿流体特征--来自包裹体、h-O同位素证据

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地质论评 2024年第2期70卷 529-540页

作者：智云宝王英鹏范海滨王巧云董健马莉谢颂诗郝兴中刘芳李瑞翔山东省地质调查院济南250014 山东省土地质量地球化学与污染防治工程技术研究中心济南250014 山东省地质矿产勘查开发局第四地质大队山东潍坊454000 山东省地质矿产勘查开发局第六地质大队山东招远265400

盘子涧金矿床地处华北板块胶辽隆起区,栖霞—蓬莱金成矿带上。金矿的形成主要与区内控矿断裂——盘子涧断裂和中生代岩浆岩有关。为研究该矿床成矿流体性质及演化,并控讨矿床成因,对该矿床不同阶段的包裹体进行岩相学、显微测温、包裹... 详细信息

盘子涧金矿床地处华北板块胶辽隆起区,栖霞—蓬莱金成矿带上。金矿的形成主要与区内控矿断裂——盘子涧断裂和中生代岩浆岩有关。为研究该矿床成矿流体性质及演化,并控讨矿床成因,对该矿床不同阶段的包裹体进行岩相学、显微测温、包裹体激光拉曼及h—O同位素分析研究。盘子涧金矿床成矿热液期可划分为4个成矿阶段,从早到晚分别是黄铁矿—石英阶段(Ⅰ阶段)、石英—黄铁矿(绢云母)阶段(Ⅱ阶段)、金—石英—多金属硫化物阶段(Ⅲ阶段)和石英—碳酸盐阶段(Ⅳ阶段)。其中Ⅱ、III阶段为主成矿阶段。不同成矿阶段的流体包裹体有3种类型,分别是富液气液两相盐水包裹体、含CO_(2)三相包裹体和纯液相包裹体。显微测温结果显示,成矿流体的完全均一温度介于142~348℃,主要集中于200~300℃,盐度介于4.44%~10.98%NaCl_(eqv)。石英的δD_(V-SMOW)值为-74.6‰~-68.5‰,δ^(18)O_(V-SMOW)值为+11.65‰~+13.92‰。显示成矿流体为中低温、低盐度的CO_(2)—h_(2)O—NaCl体系,来源于地幔,以岩浆热液为主,并伴有部分大气降水加入。矿床成因类型属石英脉型金矿。

关键词：盘子涧金矿床流体包裹体 h—O同位素胶东

纳米C-S-h晶核对水泥浆体流变性能的影响

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新型建筑材料 2024年第2期51卷 39-43页

作者：张心源倪陈新陈稳苏昂姜骞于诚江苏省交通工程建设局江苏南京210000 江苏苏博特新材料股份有限公司高性能土木工程材料国家重点实验室江苏南京211103

纳米C-S-h晶核由于对水泥早期水化的显著加速效果逐渐被广泛用作早强剂,通过流变仪测试掺纳米C-S-h晶核水泥浆体的塑性黏度、动态屈服应力、静态屈服应力和触变性,以研究纳米C-S-h晶核对水泥浆体流变性能的影响。结果表明:纳米C-S-h晶... 详细信息

纳米C-S-h晶核由于对水泥早期水化的显著加速效果逐渐被广泛用作早强剂,通过流变仪测试掺纳米C-S-h晶核水泥浆体的塑性黏度、动态屈服应力、静态屈服应力和触变性,以研究纳米C-S-h晶核对水泥浆体流变性能的影响。结果表明:纳米C-S-h晶核掺入水泥浆体后,水泥浆体塑性黏度、动态屈服应力、静态屈服应力和触变性均随之增加,掺量越大,增加越多。水灰比对水泥浆体的流变性能也具有显著影响,水灰比越小,浆体的塑性黏度、动态屈服应力、静态屈服应力和触变性越大。

关键词：纳米C-S-h晶核流变性能屈服应力触变性