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Sono-chemical Synthesis and Mechanism of Dibenz[a,c]anthracene

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Chemical Research in Chinese Universities 2012年第2期28卷 220-224页

作者： MUDDASIR Hanif wang zhi-ming LU Ping MAYu-guang State Key Laboratory for Supramolecular Structure and Materials Jilin UniversityChangchun 130012P.R.China School of Petrochemical Engineering Shenyang University of TechnologyLiaoyang 111003P.R.China

Planar polycyclic aromatic hydrocarbons have important applications in optoelectronics,environmental chemistry and cancer *** improved sono-chemical synthetic procedure of dibenz[a,c]anthracene（D[a,c]A） was reported in this *** yield was increased to 56% and the resultant was carefully characterized via gas chromatography-electron impact mass spectrometry（GC-EIMS）,matrix assisted laser desorption ionization-time of flight（MALDI-TOF）,1 H NMR,13 C NMR,correlation spectrometry（1 H1 H COSY）,heteronuclear multiple bond correlation（HMBC） and heteronuclear multiple quantum coherence（HMQC）.Based on the characterization data,we proposed a 4-step mechanistic explanation for the formation of D[a,c]A under sono-chemical bis-ortho-Wittig reaction conditions.

关键词： Phenanthrene-9 10-dione Sono-chemistry Bis-ortho-Wittig reaction mechanism NMR

Thermal and Optoelectronic Properties of Anthracene and Dibenz[a,c]Anthracene

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Chemical Research in Chinese Universities 2013年第1期29卷 110-115页

作者： MUDDASIR Hanif wang zhi-ming YANG Bing LU Ping MA Yu-guang State Key Laboratory of Supramolecular Structure and Materials Jilin University Changchun 130012 P. R. China School of Petrochemical Engineering Shenyang University of Technology Liaoyang 111003 P. R. China

The basic characteristics of anthracene（AN） and dibenz[a,c]anthracene（D[a,c]A） derivatives, important semiconductors, were systematically studied. Differential scanning calorimetry（DSC） shows that D[a,c]A has the reversibility of solid and liquid phases. Thermalgravimetric analysis（TGA） shows that D[a,c]A exhibits higher Td（decomposition temperature）, which indicates D[a,c]A, as active layers, should be more suitable to being made into stable devices. D[a,c]A shows blue-shifted UV-Vis absorption and emission despite increased conjugation compared to anthracene due to different symmetries. Both the compounds are planar and show weak blue fluorescence in the tetrahydrofuran（THF） solution and higher fluorescence in the solid-state, due to different energy levels in solution and solid-state, explained via Jablonski diagram.

关键词： Anthracene Dibenz[a,c]anthracene Molecular property Thermal Electrochemistry

Effect of Martensite Morphology on Impact Toughness of Ultra-High Strength 25CrMo48V Steel Seamless Tube Quenched at Different Temperatures

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Journal of Iron and Steel Research International 2013年第2期20卷 62-67页

作者： ZHANG Chuan-you wang Qing-feng KONG Jin-li XIE Guo-zhu wang ming-zhi ZHANG Fu-cheng State Key Laboratory of Metastable Materials Science and Technology Yanshan University National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan University

A 25CrMo48V steel for ultra-deep oil/gas well casings was quenched at 900-1 200 ℃ and tempered at 650 ℃. The lath martensitic structures were characterized by optical microscope （OM）, field emission scanning electron microscopy （FESEM）, electron backscattering diffraction （EBSD） and transmission electron microscopy （TEM）, and the transverse impact energy at 0 ℃ was measured from the as-quenched and tempered specimens. The results show that with the quenching temperature decreased, the prior austenite grain, martensitic packet and block are refined, while the lath width seems to remain unchanged. The enhancement of impact toughness with the decreasing quenching temperature can be attributed to refinement of the martensitic structure with high-angle boundaries, and the block is the minimum structure unit controlling impact toughness. The transverse impact energy [ECVN （0 ℃） ≥100 J] required for seamless casings with ultra-high strength （Rp0.2≥932 MPa） has been finally achieved with the experimental steel quenched at 900-1 000 ℃ and tempered at 650 ℃.

关键词： seamless steel tube lath martensitic morphology toughness

Mechanics model and numerical analysis of floor heave in soft rock roadway

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Journal of Coal Science & Engineering(China) 2011年第4期17卷 372-376页

作者： ZHU Chuan-qu wang Yong CHEN Miao-ming CHEN zhi wang Hong-ming Hunan Key Laboratory of Safe Mining Techniques of Coal Mines Hunan University of Science and Technology Xiangtan411201 China

The mechanism of floor heave was analyzed by establishing mechanics models and solving differential equations. The amount of floor heave is proportional to the abutment pressure of surrounding rock, roadway width, and the distance of support pressure peak to the roadway and is inversely proportional to the elastic modulus of floor rock. Using FLAC2D to simulate floor rock grouting in soft rock roadway verifies the active role of floor rock grouting in the floor controlling of soft rock roadway; floor rock grouting and grouting range directly impact on the stability scope of surrounding rock, namely, with the increase of grouting range, the subsidence of roof, the approach of both sides, and the amount of floor heave decreased gradually, the stability of surrounding rock is enhanced

关键词： soft rock roadway floor heave floor rock grouting numerical simulation

A new polyacetylene glycoside from the rhizomes of Atractylodes lancea

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Chinese Chemical Letters 2010年第7期21卷 850-852页

作者： Ying Ji Xu Feng Chao Cheng Xiao Yun Fa Dong Qi zhi wang ming wang You Yi Zhao Jiangsu Center for Research & Development of Medicinal Plants Jiangsu Institute of BotanyChinese Academy of Sciences Nanjing Botanical GardenMem.Sun Yat-SenNanjing 210014China

A new polyacetylene glycoside,（1,3Z,11E）-tridecatriene-7,9-diyne-5-hydroxyl-6-O-β-D-glucopyranoside,was isolated from the rhizomes of Atractylodes lancea（Thunb.） *** structure was elucidated on the basis of spect... 详细信息

关键词： Atractylodes lancea Polyacetylene (1 3Z 11E)-Tridecatriene-7 9-diyne-5-hydroxyl-6-O-β-D-glucopyranoside

Hall Effect of (Co_(0.34)Fe_(0.66))_(0.42)(SiO_(2))_(0.58) Granular Films

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Chinese Physics Letters 2001年第5期18卷 672-673页

作者： XU Qing-Yu NI Gang wang zhi-ming SANG Hai DU You-Wei National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093 Centre for Advanced Studies in Science and Technology of Microstructures Nanjing 210093

TheHall Effect of(Co_(0.34)Fe_(0.66))_(0.42)(SiO_(2))_(0.58)Granular Films(volume fraction)granular films were fabricated by using magnetron sputtering technique,and a saturated Hall resistivity ρ_(xys) of about 29μΩ.cm was observed at room temperature,which was almost 3 orders of magnitude greater than that in the pure ferromagnetic *** measured linear dependence of resistivity ρ_(xx) vs log_(10)T and magnetoresistance effect indicated that the Co_(0.34)Fe_(0.66) volume fraction in the films were near percolation *** giant Hall effect inHall Effect of(Co_(0.34)Fe_(0.66))_(0.42)(SiO_(2))_(0.58)Granular Films granular film may originate from percolation phenomenon.

关键词： resistivity percolation saturated

DIABETOGENIC T CELLS INDUCE AUTOIMMUNE DIABETES IN BALB/c MICE

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Chinese Medical Sciences Journal 2008年第2期23卷 88-94页

作者： Xiao-lei Zou Zeng-yu Zhao Yun-yang wang zhi-qiang Su ming Xiang Department of Pharmacology College of Pharmacy Tongji Medical College Huazhong University of Science and Technology Wuhan 430030

Objective To investigate the role of T cell and its subsets in the induction of insulifis and type 1 diabetes mellitus （T1DM） in BALB/c mice. Methods Autoimmune diabetes mellitus was developed by intraperitoneal injection of 40 mg/kg streptozotocin （STZ） daily for 5 consecutive days in BALB/c mice as sources of donor cells. Spleen cells from diabetic mice were then cultured for 7 days in the stimulation of interleukin-2 （IL-2） to harvest diabetogenic T cells, which were subse-quently transferred into normal BALB/c mice recipients. MTT, ELISA, and HE staining were used to analyze the lym- phocyte proliferation, cytokine （ IL-2, interferon-γ, IL-4, and IL-10） levels, and pathological changes in pancreatic is- lets. Results As few as 3×10^6 diabetogenic T cells successfully induced diabetes mellitus in recipients pretreated with STZ twice, whereas transfer of equal amount of normal splenocytes, T cell-depleted diabetogenic splenocytes, or diabe-togenic CD4^＋ T cells alone in recipients receiving STZ twice pretreatment was proved not to induce diabetes mellitus either. A markedly increased lymphocyte proliferation, high levels of interferon-γ/and IL-2 in the supernatants of diabeto-genic T cells were observed. In addition, a markedly enhanced lymphocyte proliferation, a high level of interferon-γ/secretion in serum, and numerous lymphocytes infiltration in pancreatic islets were detected in the diabetic mice induced by diabetogenic T cells transfer. Conclusions A novel T1DM murine model is established in STZ-pretreated BALB/c mice by adoptive transfer of diabetogenic T cells. CD4^＋ T cells with interferon-γ/may promote the onset of diabetes mellitus.

关键词： diabetogenic T cells adoptive transfer streptozotocin-induced diabetes mellitus

Effect of RNA Interference Hsp72 Gene Expression on Development of Mouse Preimplantation Embryos

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Agricultural Sciences in China 2009年第2期8卷 223-230页

作者： wang ming-zhi TIAN Wen-ru TIAN Zhong-jie QU Ping-ping GAO Shan-song ZHANG zhi-hong ZHANG Qi-yao HOU Chun-xia LI Hui-hui College of Animal Science and Veterinary Medicine Qingdao Agricultural University Qingdao 266109 P.R.China

The method of RNAi was used to inhibit the expression of induced heat shock protein 70 （Hsp72） in the 4-cell stage mouse embryos and the embryo development competence was analyzed to identify the functions of Hsp72 on embryonic heat resistance. The results indicated that the inhibition rates of siRNA1 for Hsp72 mRNA and Hsp72 protein were 87.1 and 78.5%, respectively. The blastocysts development rates were 41, 86, and 84% for the siRNA1 group, the LipofectamineTM 2 000 exposed group, and the 37℃ group, respectively, and the hatched blastocysts development rates for the above three groups were 35, 72, and 68%, respectively. The data suggest that the siRNAI has a significant inhibiting effect on Hsp72 gene, and Hsp72 gene silence reduces the blastocysts development rate and hatched blastocysts rate after heat shock during the development of mouse preimplantation embryos.

关键词： RNA interference mouse blastocyst Hsp72 gene

Ab Initio Studies on Eight Electronic States of the BH_2 Radical

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Chemical Research in Chinese Universities 1993年第1期9卷 59-64页

作者： GU Jian-ping wang zhi-xiang and HUANG ming-bao (Department of Modern Chemistry, University of Science and Technology of China, Hefei, 230026)

The present paper covers ab initio UHF calculations with a d, p-polarized basis set performed for eight electronic states of BH2 and the equilibrium geometries, electronic term values Tc and vibrational frequencies of the five stable states X2A1, 2B1, 2B2, 22A1 and 2A2. On the basis of the UHF results, the states 22B2. 2B1 and 32A1 are predicted to be unstable. The MP2/6-31G * * calculations were performed for the X2A1 and 2B1, states, and the calculated equilibrium geometries, Tc value and vibrational frequencies are similar to the UHF results. The MP2/6-31G * * studies on the reaction BH2→BH + H for the X2A1 and 2B1 states were carried out and the HB-H bond energies of these two states were calculated.

关键词： Ab initio calculation Electronic excited state Borane( Ⅱ )