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Inhibition of nitric oxide synthase aggravates brain injury in diabetic rats with traumatic brain injury

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Neural Regeneration Research 2021年第8期16卷 1574-1581页

作者： wan-Chao Yang Hong-Ling Cao Yue-Zhen wang Ting-Ting Li Hong-Yu Hu qiang wan Wen-Zhi Li Department of Anesthesiology The Second Affiliated Hospital of Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Department of Anesthesiology Jilin Province Tumor HospitalChangchunJilin ProvinceChina

Studies have shown that hyperglycemia aggravates brain damage by affecting vascular endothelial function. However, the precise mechanism remains unclear. Male Sprague-Dawley rat models of diabetes were established by a high-fat diet combined with an intraperitoneal injection of streptozotocin. Rat models of traumatic brain injury were established using the fluid percussion method. Compared with traumatic brain injury rats without diabetic, diabetic rats with traumatic brain injury exhibited more severe brain injury, manifested as increased brain water content and blood-brain barrier permeability, the upregulation of heme oxygenase-1, myeloperoxidase, and Bax, the downregulation of occludin, zona-occludens 1, and Bcl-2 in the penumbra, and reduced modified neurological severity scores. The intraperitoneal injection of a nitric oxide synthase inhibitor N(5)-(1-iminoethyl)-L-ornithine(10 mg/kg) 15 minutes before brain injury aggravated the injury. These findings suggested that nitric oxide synthase plays an important role in the maintenance of cerebral microcirculation, including anti-inflammatory, anti-oxidative stress, and anti-apoptotic activities in diabetic rats with traumatic brain injury. The experimental protocols were approved by the Institutional Animal Care Committee of Harbin Medical University, China(approval No. ky2017-126) on March 6, 2017.

关键词： apoptosis blood-brain barrier brain edema diabetes mellitus inflammation injury neurological function nitric oxide synthase traumatic brain injury

液质联用法结合自动固相萃取同时测定药食同源杂粮中14种真菌毒素

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粮食与油脂 2024年第8期37卷 146-150页

作者：黄忠亮王海波廖强李琬婧吴张静覃弘毅广西壮族自治区医疗器械检测中心广西南宁530031 广西-东盟食品检验检测中心广西南宁530029 广西壮族自治区食品药品审评查验中心广西南宁530029 南宁市食品药品检验所广西南宁530000

建立液相色谱-串联质谱法结合自动固相萃取同时测定药食同源杂粮中14种真菌毒素的方法。样品经乙腈-水溶液(体积比6:4)提取,再利用一步法快速净化柱(QMyco-Multi)在自动固相萃取仪上完成快速净化,最后通过液相色谱分离,在电喷雾离子源(E... 详细信息

建立液相色谱-串联质谱法结合自动固相萃取同时测定药食同源杂粮中14种真菌毒素的方法。样品经乙腈-水溶液(体积比6:4)提取,再利用一步法快速净化柱(QMyco-Multi)在自动固相萃取仪上完成快速净化,最后通过液相色谱分离,在电喷雾离子源(ESI)正负离子模式下同时进行多重反应离子监测(MRM)。结果表明:14种真菌毒素在不同质量浓度范围内线性关系良好(相关系数>0.99),定量限为0.2~10.0μg/kg,加标回收率为81%~117%,相对标准偏差(RSD)为2.0%~7.2%(n=6)。制备的方法简单快速、灵敏准确,可用于药食同源杂粮中14种真菌毒素的同时测定。

关键词：药食同源杂粮真菌毒素一步法快速净化自动固相萃取

Soil Microbial Responses to Experimental Warming and Nitrogen Addition in a Temperate Steppe of Northern China

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Pedosphere 2014年第4期24卷 427-436页

作者： SHEN Rui-Chang XU Ming CHI Yong-Gang YU Shen wan Shi-qiang Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of Sciences University of Chinese Academy of Sciences Center for Remote Sensing and Spatial Analysis Department of EcologyEvolution and Natural ResourcesRutgers University14College Farm RoadNew Brunswick NJ 08901(USA) Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of Sciences Key Laboratory of Plant Stress Biology College of Life SciencesHenan University

The responses of soil microbes to global warming and nitrogen enrichment can profoundly affect terrestrial ecosystem functions and the ecosystem feedbacks to climate ***,the interactive effect of warming and nitrogen enrichment on soil microbial community is *** this study,individual and interactive effects of experimental warming and nitrogen addition on the soil microbial community were investigated in a long-term field experiment in a temperate steppe of northern *** field experiment started in 2006 and soils were sampled in 2010 and analyzed for phospholipid fatty acids to characterize the soil microbial *** soil chemical properties were also ***-year experimental warming significantly increased soil total microbial biomass and the proportion of Gram-negative bacteria in the ***-term nitrogen addition decreased soil microbial biomass at the 0-10 cm soil depth and the relative abundance of arbuscular mycorrhizal fungi in the *** interactive effect on soil microbes was detected when experimental warming and nitrogen addition were *** microbial biomass positively correlated with soil total C and N,but basically did not relate to the soil C/N ratio and *** results suggest that future global warming or nitrogen enrichment may significantly change the soil microbial communities in the temperate steppes in northern China.

关键词： arbuscular mycorrhizal fungi global warming Gram-negative bacteria nitrogen enrichment microbial biomass microbial community

In situ polymerization of aniline in electrospun microfibers

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Chinese Chemical Letters 2014年第1期25卷 83-86页

作者： Xiao-qiang Li wan-wan Liu Shui-Ping Liu Meng-Juan Li Yong-Gui Li Ming-Qiao Ge Key Laboratory of Eco-textiles Ministry of EducationJiangnan University College of Textile & Clothing Jiangnan University

Conductive microfibers with an average diameter of ca. 1.0 μm were prepared by in situ polymerization of aniline, in which poly（vinylchloride-acrylonitrile）（PVC-AN） was used as the filament-material in electrospinning to form precursor microfibers and carry the aniline monomers. Fourier-transform infrared （FTIR） results demonstrated that PANi was successfully polymerized in the microfibers. The morphology of the PVC-AN-PANi microfibers was observed by scanning electron microscopy （SEM）. Results of differential scanning calorimetry indicated that the polymer composite of PVC-AN-PANi formed via molecular interactions. Although the conductivity of PVC-AN-PANi microfibers was still limited （2.2 × 10^-8 S/cm）, this method provided an effective and convenient approach for preparing highly uniform and soft microfibrous electrodes.

关键词： Conductive microfibers Electrospinning Polymer composite Polyaniline

Microstructure and mechanical properties of TiAl/Ni-based superalloy joints vacuum brazed with Ti-Zr-Fe-Cu-Ni-Co-Mo filler metal

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Rare Metals 2021年第8期40卷 2134-2142页

作者： Bao wan Xiao-qiang Li Cun-Liang Pan Dong-Yu Li Sheng-Guan Qu Chao Yang National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou510640China

For the purpose of elevated temperature service and weight reduction in aerospace vehicle applications,a novel Ti-Zr-Fe-Cu-Ni-Co-Mo filler metal was employed to join TiAl to Ni-based superalloy(GH536).The effects of brazing temperature on interfacial microstructure and chemical composition of the joints were *** representative joint microstructure from TiAl substrate to GH536 substrate was primarily composed of four characteristic layers in order:B_(2);Al_(3)NiTi_(2);AlNi_(2)Ti containing Cr-rich(Cr,Ni,Fe)_(ss)(subscript ss represents solid solution),Ni-rich(Ni,Cr,Fe)_(ss) and TiNi3;Cr-rich(Cr,Ni,Fe)_(ss)containing AlNi_(2)Ti,Ni-rich(Ni,Cr,Fe)_(ss) and *** IV has the majority of the brazing seam,while LayerⅡwas the *** the thickness of LayerⅡwas not affected by brazing *** the increase in brazing temperature in the range of 1110-1170℃,both the shear strength and the thickness of brazing seam firstly increased and then *** joint performance was jointly controlled by the thickness of brazing seam,the amounts of microcracks and intermetallic compounds formed in brazing *** maximum shear strength of 183 MPa at room temperature was obtained together with a peak thickness when the joint was brazed at 1150℃for 10 min and the shear fracture mainly occurred in the thinnest LayerⅡAl_(3)NiTi_(2).

关键词： TiAl alloy Ni-based superalloy Brazing Microstructure Shear strength

Self-template synthesis of hollow Fe-doped CoP prisms with enhanced oxygen evolution reaction activity

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Journal of Energy Chemistry 2021年第11期30卷 415-422,I0009页

作者： Xueda Ding Haitao Huang qiang wan Xu Guan Yuanxing Fang Sen Lin Dongyang Chen Zailai Xie College of Materials Science and Engineering Fuzhou UniversityFuzhou 350116FujianChina Fujian Provincial Key Laboratory of Electrochemical Energy Storage Materials College of ChemistryFuzhou UniversityFuzhou 350116FujianChina

The development of efficient, durable and low cost electrocatalysts is crucial but extremely challenging for the oxygen evolution reaction (OER). Herein, we develop a self-template strategy to synthesize hollow Fe-doped CoP prisms (Fe-CoP) via ion exchange of cobalt acetate hydroxide with [Fe(CN)_(6)]^(3-) and phosphorization-induced transformation of CoFe-PBA (Co/Fe-containing prussian blue analogue) prisms in N2 atmosphere. The obtained Fe-CoP not only inherits the hollow prism-like morphology of CoFe-PBA, but also forms rich mesoporous channel. The Fe-CoP prisms exhibit extraordinary OER performances in 1.0 M KOH, with a low overpotential of 236 mV to deliver a current density of 10 mA cm^(−2) and a low Tafel slope of 32.9 mV dec^(–1). Moreover, the presented electrocatalyst shows good long-term operating durability and activity. The XPS and TEM analysis confirm that Fe-CoP has undergone surface reconstruction in the process of electrocatalytic OER, and the in situ formed oxides and oxyhydroxides are the real active species to boost OER. This work provides a promising pathway to the design and synthesis of efficient and robust electrocatalysts with hierarchical hollow structure for boosting OER.

关键词： Prussian blue analogue Hollow structure Fe-doped CoP Oxygen evolution reaction

Time-sequenced damage behavior of reactive projectile impacting double-layer plates

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Defence Technology(防务技术) 2023年第9期27卷 263-272页

作者： Ying Yuan Yi-qiang Cai Huan-guo Guo Peng-wan Chen Rui Liu Hai-fu wang Beijing Institute of Technology Beijing100081China

The time-sequenced damage behavior of the reactive projectile impacting double-layer plates is *** analytical model considering the combined effect of kinetic and chemical energy is developed to reveal the damage *** influences of impact velocity and reactive projectile chemical characteristics on the damage effect are decoupled analyzed based on this *** analyses indicate that the high energy releasing efficiency and fast reaction propagation velocity of the reactive projectile are conducive to enhancing the damage *** experiments with various reactive projectiles impact velocity increasing from 702 to 1385 m/s were conducted to verify this *** experimental results presented that,the damage hole radius of the rear-plate increases with the increase of impact *** the impact velocity of 1350 m/s,the radius of damage hole formed by PTFE/Al/Bi_(2)O_(3),PTFE/Al/MoO_(3),PTFE/Al/Fe_(2)O_(3)projectile on the rear-plate become smaller in *** results are consistent with the analytical model prediction,demonstrating that this model can predict the damage effect *** work is of constructive significance to the application of reactive projectiles.

关键词： Reactive projectile Damage behaviors Impact Double-layer plates

Photochromism of 36-Armed Liquid Crystalline Dendrimer

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Chinese Chemical Letters 2005年第10期16卷 1371-1374页

作者： Jian qiang LIU Qi Zhen ZHANG Jing Zhi ZHANG wan Guo HOU School of Physics and Microelectronics Shandong University Ji＇nan 250100 Key Laboratory of Education Ministry on Colloid ＆ Interface Chemistry Ji＇nan 250100 School of Chemistry and Chemical Engineering Shandong University Ji＇nan 250100

The photochromism of a 36-armed liquid crystalline dendrimer D6 was briefly described in this paper. The molar absorption coefficient, photoisomerization and photo back-isomerization of D6 in solution were investigated by UV/Vis absorption spectra. The results indicate that the photochromism and photo back-isomerization of D6 in chloroform （CHC13） and tetrahydrofuran （THF） solutions are in accordance with the ftrst order kinetics. The photochromism rate constants of D6 are 101 sI, it is 107 times larger than that of side-chain liquid crystalline polymers containing the same azobenzene moieties.

关键词： Photochromism liquid crystalline dendrimer photo back-isomerization.

Dehydrogenation characteristics of ZrC-doped LiAlH4 with different mixing conditions

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Rare Metals 2020年第4期39卷 383-391页

作者： Zi-Liang Li Fu-qiang Zhai Hao-Chen Qiu Qi wan Ping Li Xuan-Hui Qu State Key Laboratory for Advanced Metals and Materials Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China Applied Physics Department Polytechnic University of Catalonia-Barcelona08860 CastelldefelsSpain Research Institute of Energy and Materials Technology General Research Institute of Nonferrous MetalsBeijing 100088China

The catalytic effects of ZrC powder on the dehydrogenation properties of LiAlH4 prepared by designed mixing processes were systematically *** onset dehydrogenation temperatures for the 10 mol% ZrC-doped sample are 85.3 and 148.4℃for the first two dehydrogenation stages,decreasing by 90.7 and 57.8℃,respectively,compared with those of the as-received *** isothermal volumetric measurement indicates that adding ZrC powder could significantly enhance the desorption kinetics of *** reaction constant and Avrami index show that the first dehydrogenation stage is controlled by diffusion mechanism with nucleation rate gradually decreasing and the second stage is a freedom nucleation and subsequent growth *** microstructures and phase transformation characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS) and Fourier transform infrared spectroscopy(FTIR) reveal that the improved desorption behavior of LiAlH4 is primarily due to the high density of surface defects and embedded catalyst particles on the surface of LiAlH4 particles during the high-energy mixing process.

关键词： Lithium alanate Zirconium carbide Doping methods Dehydrogenation performances Catalytic mechanism