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991.
对梅州农村饮用水中的重金属元素进行了监测和分析,选择Fe,Mn,Zn,Cu,Ag,Pb,Cd七种元素为检测指标。从实验结果来看,Cu,Ag,Cd含量低,未超标;Fe,Mn,Zn,Pb有超标现象:按其危害程度,Pb,Mn的超标是急需解决的问题。 相似文献
992.
Five new eclipsed two-dimensional (2D) coordination polymers, [[Cd(2)(TPT)(2)L(2)](GM(1))(3/2)(H(2)O)](infinity) (1) (TPT = terephthalate, L = 3-(2-pyridyl)pyrazole, GM(1) = terephthalic acid), [[Cd(TPT)L](GM(2))(H(2)O)(2)]( infinity) (2) (GM(2) = L = 3-(2-pyridyl)pyrazole), [[Cd(TPT)L](GM(3))(1/2)(H(2)O)](infinity) (3) (GM(3) = mesitylene), [[Cd(4)(TPT)(4)L(4)](GM(4))(7/2)](infinity) (4) (GM(4) = tetramethylbenzene), and [[Cd(TPT)L](GM(5))(1/2)](infinity) (5) (GM(5) = naphthalene), have been synthesized and characterized by X-ray diffraction. All the five complexes take the similar eclipsed 2D open-channel framework with different guest molecules included in the cavities of their channels. TGA analysis indicates that the eclipsed open-channel frameworks are thermally stable up to 300 degrees C. The porous property of the 2D framework of 5 was also investigated by the XRPD technique, which indicated that the guest molecules included in the open-channel frameworks are removable and the framework is maintained after the removal of the guest molecules. Moreover, complexes 1-5 also display strong blue emission in the solid state. 相似文献
993.
Gintaras Pivoriunas Ccilia Maichle‐Mssmer Simon Schwarz Joachim Strhle 《无机化学与普通化学杂志》2005,631(10):1743-1745
Synthesis and Crystal Structure of [(Ph3PAu)3NPPh3][PF6]2, a Gold(I) Phosphoraneiminato Complex The photolytic reaction of Ph3PAuN3 with Cr(CO)6 in THF yields the phosphoraneiminato complex [(Ph3PAu)3NPPh3]2+ in low yield as well as the cluster cation [(Ph3PAu)8]2+ as the main product. The phosphoraneiminato complex crystallizes from CH2Cl2 with [PF6]? ions as [(Ph3PAu)3NPPh3][PF6]2·CH2Cl2 in the triclinic space group with a = 1200.8(1), b = 1495.6(2), 2053.5(5), α = 86.97(2)°, β = 82.79(1)°, γ = 81.87(2)°, and Z = 2. The phosphoraneiminato ligand bridges through its N atom three Au atoms, which itself are connected to each other by weak aurophilic interactions. 相似文献
994.
995.
Qing-shan Liang Jian-Gang Xie ChaoPing Yu ZhuSheng Feng JingChang Ma Yuan Zhang Dong Wang JianGuo Lu Ran Zhuang Jikai Yin 《Experimental & molecular medicine》2021,53(3):393
Splenectomy has been reported to improve liver fibrosis in patients with cirrhosis and hypersplenism. However, the mechanisms remain unclear. Tumor necrosis factor superfamily 14 (TNFSF14; also known as LIGHT) is highly expressed in the context of fibrosis and promotes disease progression in patients with fibrotic diseases such as pulmonary and skin fibrosis. Here, we determined whether splenectomy controls the production of LIGHT to improve liver fibrosis. Splenectomy reduced serum LIGHT levels in cirrhotic patients with hypersplenism and a ConA-induced liver fibrosis mouse model. Blocking LIGHT resulted in the downregulation of TGF-β1 in RAW264.7 cells. LIGHT treatment of RAW264.7 and JS1 cells in coculture regulated transforming growth factor-β1 (TGF-β1) expression through the activation of JNK signaling. Small interfering RNA-mediated silencing of lymphotoxin β receptor (LTβR) in macrophages resulted in pronounced decreases in the levels of fibrosis and αSMA in JS1 cells. These results indicated that LIGHT bound to LTβR and drove liver fibrosis in vitro. Blocking TGF-β1 abolished the effect of LIGHT in vitro. Furthermore, the administration of recombinant murine LIGHT protein-induced liver fibrosis with splenectomy, while blocking LIGHT without splenectomy improved liver fibrosis in vivo, revealing that the decrease in fibrosis following splenectomy was directly related to reduced levels of LIGHT. Thus, high levels of LIGHT derived from the spleen and hepatic macrophages activate JNK signaling and lead to increased TGF-β1 production in hepatic macrophages. Splenectomy attenuates liver fibrosis by decreasing the expression of LIGHT.Subject terms: Tumour-necrosis factors, Liver fibrosis, Hepatic stellate cells, Liver cirrhosis, Experimental models of disease 相似文献
996.
Novel furo, thieno and pyrrolo[2,3‐b]pyrazole cyanine dyes were synthesized. The structure‐photosensitization properties correlation of the dyes were examined in 95% ethanol solution by absorption spectroscopy. The chemical structure of the starting biheterocyclic compounds and their derived cyanine dyes were confirmed by elemental analysis, IR and 1H NMR spectroscopy. 相似文献
997.
Hoong‐Kun Fun Qingli Hao Jiang Wu Xujie Yang Lude Lu Xin Wang Suchada Chantrapromma Ibrahim Abdul Razak Anwar Usman 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):m87-m88
In the structure of the title compound, [CuII(en)2][(EtO)2P(S)S]2 (en is ethylenediamine) or [Cu(C2H8N2)2](C4H10O2PS2)2, the Cu atom lies on a center of inversion and is coordinated in a slightly distorted square coordination geometry by four N atoms from two ethylenediamine molecules. The diethyl dithiophosphate moieties, (EtO)2P(S)S?, act as counter‐anions. 相似文献
998.
We describe a synthetic investigation on the formation of carbon nanofibers using a preshaped free-standing metal-oxide catalyst (single-crystal cobalt oxide (Co(3)O(4)) nanocubes). In reacting with acetylene (C(2)H(2)) vapor, Co(3)O(4) nanocubes are reduced and reconstructed into metallic cobalt. The resultant metal catalyst with a 2-fold symmetry leads to a bilateral base growth for carbon nanofibers. Our findings indicate that an understanding of catalyst-assisted chemical vapor deposition (CVD) mechanisms can be acquired, when the shape, size, and crystal orientation of pristine metal catalysts are made known to the CVD process. By tracing their evolutional changes in structure and composition, the shape-designed model catalysts may offer new opportunities for mechanistic investigations on the chemical reactivity of nanoparticles, general catalyst-assisted material synthesis, and metal intercalation chemistry. 相似文献
999.
IntroductionConsiderableattelltionisno\vbeillgpaidtotheCO7refonningof.etha..llto]forseveralreasonst(l)withthedevelopmentofindustrics.moreandnlorcCOZIsabettedintotheatmosphere,leadingto"greenhouseeffect",whichhasbroughtaboutgreatilltcreslallovertheworld.Th… 相似文献
1000.
介绍了非均匀相催化剂的MOVS制备方法,以该法制得的MoO3催化剂在甲醇选择氧化制甲醛、CO加氢制高级和喹啉加氢脱氮中均显示出常规催化剂更为优异的催化性能,并探讨了MOVS催化剂的内在特性与催化性能的关系。 相似文献