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81.
两种含锌化合物对慢性染铅大鼠海马NADPH-d阳性神经元影响的比较 总被引:1,自引:0,他引:1
为探讨硫酸锌(ZnSO4)和牛磺酸锌(TZC)拮抗铅对学习记忆的损害的不同,采用NADPH-黄递酶(NADPH-d)组化,观察了饮用含0.2g/L醋酸铅(PbAc)饮水和含不同剂量(5.0,15.0g/kg)ZnSO4、(5.9、17.7g/kg)TZC饲料喂养的大鼠海马一氧化氮合酶(NOS)活性的变化。结果表明,各补锌组均不同程度地缓解铅致NOS活力减低,铅 低TZC组、铅 高ZnSO4组和铅 低ZnSO4组大鼠海马神经元的NOS活性明显高于染铅组,其中铅 低TZC组的保护作用最显著,而铅 高TZC组的NOS活性明显低于对照组,而接近染铅组水平。结论是锌对抗铅的毒性作用与锌的化学结合形式、锌的剂量密切相关。 相似文献
82.
Bo Jiang Hui Song Yunqing Kang Shengyao Wang Qi Wang Xin Zhou Kenya Kani Yanna Guo Jinhua Ye Hexing Li Yoshio Sakka Joel Henzie Yamauchi Yusuke 《Chemical science》2020,11(3):791
Generating high surface area mesoporous transition metal boride is interesting because the incorporation of boron atoms generates lattice distortions that lead to the formation of amorphous metal boride with unique properties in catalysis. Here we report the first synthesis of mesoporous cobalt boron amorphous alloy colloidal particles using a soft template-directed assembly approach. Dual reducing agents are used to precisely control the chemical reduction process of mesoporous cobalt boron nanospheres. The Earth-abundance of cobalt boride combined with the high surface area and mesoporous nanoarchitecture enables solar-energy efficient photothermal conversion of CO2 into CO compared to non-porous cobalt boron alloys and commercial cobalt catalysts.Generating high surface area mesoporous transition metal boride is challenging but interesting because incorporation of boron atoms can generate lattice distortion to form amorphous metal boride which has unique properties in catalysis. 相似文献
83.
含聚醚间隔链的扩链脲改性环氧树脂/双氰双胺固化体系性能研究 总被引:1,自引:0,他引:1
合成了一系列含不同分子量聚环氧丙烷 (PPG)柔性间隔链的扩链脲 ,系统考察了扩链脲改性环氧树脂E 5 1/双氰双胺 (dicy)固化体系的固化反应活性、动态力学行为、冲击性能和断裂面形态结构 ,并对体系的冲击性能、形态结构与动态力学行为之间的关系进行了探讨 .结果表明 ,改性体系固化反应活性明显提高 ,固化反应表观活化能降低 ,固化反应峰顶温度从 190℃降低至 14 0℃ ,固化反应的表观活化能由 14 5 5kJ/mol降至 70~ 80kJ mol;改性体系冲击强度明显提高 ,其中所含PPG柔性链分子量为 10 0 0的扩链脲改性的E 5 1/dicy体系冲击强度较未改性的E 5 1/dicy体系提高了 8倍 ,其冲击试样断裂面的形态具有明显的韧性断裂特征 ,微观两相网络结构的存在导致了改性体系冲击强度显著提高 相似文献
84.
Xin Yang Chuan Dong Jun Zhang Yan-sheng Wei Wei-Jun Jin Chang-song Liu 《Microchemical Journal》1997,57(3):294-304
Six polycyclic aromatic hydrocarbons (PAHs) are studied by chemical deoxygenation microemulsion-stabilized room temperature phosphorimetry with sodium sulfite as an oxygen scavenger and thallous nitrate as a heavy atom perturber in sodium dodecyl sulfate medium. Several factors influencing room temperature phosphorescence such as the concentration of sodium dodecyl sulfate, the heavy atom concentration, the pH, and the concentration of sodium sulfite are discussed and the quenching effect of NO2−on room temperature phosphorimetry of PAHs was compared in the microemulsion and micelle media. 相似文献
85.
Diao Hongyue Deng Ansheng Cui Hui Liu Xin Zou Li 《Fuzzy Optimization and Decision Making》2022,21(1):45-69
Fuzzy Optimization and Decision Making - Linguistic information processing exists in multi-criteria decision making, and linguistic truth-valued lattice implication algebra (LTV-LIA) has definite... 相似文献
86.
Xin Liu 《Graphs and Combinatorics》1995,11(3):267-273
LetG be ak-connected (k 2) graph onn vertices. LetS be an independent set ofG. S is called essential if there exist two distinct vertices inS which have a common neighbor inG. LetV
r, be a clique which is a complete subgraph ofG. In this paper it is proven that if every essential independent setS ofk + 1 vertices satisfiesS V
r , thenG is hamiltonian, orG{u} is hamiltonian for someu V
r, orG is one of three classes of exceptional graphs. Our theorem generalizes several well-known theorems. 相似文献
87.
ULTRASONICALLY DISPERSED POTASSIUM AS DEPROTONATING AND COUPLING AGENT──SYNTHESIS OF 1,6-DINITRILES IN SITUULTRASONICALLYDISP... 相似文献
88.
The addition of carboxylic acids to terminal alkynes is efficiently catalyzed by the early transition-metal complex Re(CO)5Br in toluene or n-heptane at 110 degrees C in an air atmosphere, affording the anti-Markovnikov adducts in good yields with high selectivity. In most cases, the reactions afford unusual Z-adduct predominantly. When n-heptane was used as solvent, Re(CO)5Br can be partly recovered from the reaction mixture. 相似文献
89.
A novel layered K(4)Ag(2)Sn(3)S(9) x 2KOH was synthesized solvothermally. A mixture of ethanol and HSCH(2)CH(SH)CH(2)OH was used for the synthesis. The HSCH(2)CH(SH)CH(2)OH plays an important role and appears to serve as a mineralizer for the solvothermal reaction. A layer comprises Sn(3)S(9)(6)(-) clusters linked by Ag(+) ions and possesses two types of 1D channels in which potassium ions are located. The compound crystallizes in the monoclinic P2(1)/m space group [a = 7.8071(2) A, b = 27.3508(1) A, c = 10.5008(2) A, alpha = 90 degrees, beta = 103.874(1) degrees, gamma = 90 degrees, Z = 4]. Its crystal structure, composition analysis, and IR are presented. 相似文献
90.