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4-[(Furan-2-ylmethylene)-amino]-1,5-dimethyl-1,2-dihyl-1,2-dihydo-pyrazol-3-one

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Chinese Journal of Structural Chemistry 2005年第11期24卷 1310-1313页

作者： LI zong-Xiao zhang Xin-Li Department of Chemistry Baoji University of Arts and Science Baoji 721007 China

The title compound （C16H15N3O2, Mr= 281.31） has been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. The Schiff base compound is a derivative of 4-aminoantipyrine. As expected, the molecular structure adopts a trans configuration about the C=N double bond. It crystallizes in the monoclinic system, space group P2 1/c with a = 11.150（3）, b = 9.906（3）, c = 13.624（4） A, β = 106.360（4）°, V= 1443.9（7） ,A^3, Z = 4, Dc = 1.294 g/cm^3, F（000） = 592,μ（MoKa） = 0.088 mm ^-1, R = 0.0577 and wR = 0.1214. Of the 5766 total reflections, 2540 were unique. In the molecule there exist two different planes of pyrazoline and O（2）-C（10） phenyl ring, which are approximately coplanar （r.m.s. de deviation from the combined mean plane is 0026 A） with the dihedral angle between them of 6.3°.

关键词： 4-[(furan-2-ylmethylene)-amino]-1,5-dimethyl-1,2-dihyl-1,2- dihydo-pyrazol-3-one,crystal structure antipyrine derivative

Comparative identification of Ca～(2+) channel expression in INS-1 and rat pancreatic β cells

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World Journal of Gastroenterology 2009年第24期15卷 3046-3050页

作者： Fei Li zong-Ming zhang Department of General Surgery Digestive Medical Center The First Affiliated Hospital Medical School Tsinghua University Beijing 100016 China

AIM： To identify and compare the profile of Ca^2＋ channel subunit expression in INS-1 and rat pancreatic β cells.METHODS： The rat insulin-secreting INS-1 cell line was cultured in RPMI-1640 with Wistar rats employed as islet donors. Ca^2＋ channel subunit expression in INS-1 and isolated rat β cells were examined by reverse transcription polymerase chain reaction （RT-PCR）. Absolute real-time quantitative PCR was performed in a Bio-Rad iQ5 Gradient Real Time PCR system and the data analyzed using an iQ5 system to identify the expression level of the Ca^2＋ channel subunits. RESULTS： In INS-1 cells, the L-type Ca^2＋ channel 1C subunit had the highest expression level and the TPRM2 subunit had the second highest expression. In rat β cells, the TPRC4β subunit expression was dominant and the expression of the L-type lC subunit exceeded the 1D subunit expression about two-fold. This result agreed with other studies, confirming the important role of the L-type lC subunit in insulinsecreting cells, and suggested that non-voltage-operated Ca^2＋ channels may have an important role in biphasic insulin secretion. CONCLUSION： Twelve major Ca^2＋ channel subunit types were identified in INS-1 and rat β cells and significant differences were observed in the expression of certain subunits between these cells.

关键词： L-type calcium channels Expression profile Insulin-secreting cells Rats pancreatic β cell Reverse transcription-polymerase chain reaction

QQqq Four-Quark Bound States in Chiral SU(3) Quark Model

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Communications in Theoretical Physics 2008年第8期50卷 437-440页

作者： zhang Ming zhang Hai-Xia zhang zong-Ye Institute of High Energy Physics the Chinese Academy of Sciences P.O. Box 918-4 Beijing 100049 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China School of Biomedical Engineering Capital Medical University Beijing 100069 China

Abstract The possibility of QQqq heavy-light four-quark bound states has been analyzed by means of the chiral SU（3） quark model, where Q is the heavy quark （c or b） and q is the light quark （u, d, or s）. We obtain a bound state for the bbnn configuration with quantum number JR=1^＋, I = 0 and for the ccnn （JR=1^＋, I=O） configuration, which is not bound but slightly above the D^＊ D^＊ threshold （n is u or d quark）. Meanwhile, we also conclude that a weakly bound state in bbnn system can also be found without considering the ehiral quark interactions between the two light quarks, yet its binding energy is weaker than that with the chiral quark interactions.

关键词： four-quark states quark model chiral symmetry

Failure of hanging roofs in sublevel caving by shock collision and stress superposition

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Journal of Rock Mechanics and Geotechnical Engineering 2016年第6期8卷 886-895页

作者： zong-Xian zhang Department of Arctic Technology University Center in Svalbard

Hanging roofs or high hang-ups.a common problem in sublevel caving mining,usually result in a large ore loss and undermine mining *** paper analyzed the formation of a hanging roof and showed that increased confining pressure and reduced free surface were its main *** order to break down a hanging roof,a new method based on shock wave collision and stress superposition was *** this method,two blastholes containing multi-primer at different positions are simultaneously initiated at *** doing this,a new free surface and a swell room can be *** these holes are fired,a long delay time is given to the next blasthole so that the fragments from the first twohole blasting have enough time to fall *** new method was applied to three hanging roofs in one production area,and all of them were successfully broken *** inspection indicated that almost no damage was caused in the nearby drifts/tunnels due to the new *** addition,the far field vibrations were found to be smaller than the maximum vibrations induced by some other blasts.

关键词： Shock wave collision Hanging roof Sublevel caving Rock fracture Hang-up Underground mining

Study on the flow structure in curved open channels with suspended vegetation using multi relaxation time lattice Boltzmann method

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Journal of Hydrodynamics 2024年第2期36卷 300-315页

作者： He-fang Jing Qiao-ling zhang Wei-hong Wang zong-ning zhang School of Mathematics and Information Science North Minzu UniversityYinchuan750021China School of Civil Engineering North Minzu UniversityYinchuan750021China Department of Basic Courses Zhengzhou University of Science and TechnologyZhengzhou450064China

Suspended vegetation in rivers,lakes,reservoirs and canals can change flow structure,which will in turn affect the sediment transport and cause the variation of water ecological *** order to study the characteristics of bend flow through suspended vegetation,three-dimensional numerical simulations are carried out by using the multi-relaxation-time lattice Boltzmann method(MRT-LBM).The drag force induced by vegetation is added in the velocity correction in the equilibrium distribution and a hybrid format combined bounce and specular reflection scheme is applied in the solid-fluid *** the validation of this model,six cases are designed to conduct the numerical simulations according to the root depth and the arrangement of *** simulated results show that the suspended vegetation can redistribute the flow structure in curved open *** the arrangement of suspended vegetation,the main flow moves to the side without vegetation,and the distribution of velocity tends to be balanced when vegetation is arranged on the entire cross section,the range of circulating current is reduced from the whole cross section to the local position without vegetation,however,the circulating current can still exist in the curve where the suspended vegetation enters less than half of the water *** addition,it can also be concluded that the suspended vegetation can affect the lateral gradient of flow velocity,and the bed shear stress in the curved channel.

关键词： Multi-relaxation-time lattice Boltzmann method(MRT-LBM) suspended vegetation curved open channel circulating current bed shearstress

An empirical approach for predicting burden velocities in rock blasting

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第4期13卷 767-773页

作者： zong-Xian zhang Li-Yuan Chi Changping Yi Oulu Mining School University of OuluOuluFI-90014Finland State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijingChina Division of Mining and Geotechnical Engineering Lulea University of TechnologyLuleaSweden

An analytical relation between burden velocity and ratio of burden to blasthole diameter is developed in this *** relation is found to be consistent with the measured burden velocities of all 37 full-scale blasts found from published *** blasts include single-hole blasts,multi-hole blasts,and simultaneously-initiated blasts with various borehole diameters such as 64 mm,76 mm,92 mm,115 mm,142 mm and 310 *** boreholes were fully *** agreement between measured and calculated burden velocities demonstrates that this relation can be used to predict the burden velocity of a wide range of full-scale blast with fully-coupled explosive charge and help to determine a correct delay time between adjacent holes or rows in various full-scale blasts involved in tunnelling(or drifting),surface and underground mining production blasts and underground opening slot *** addition,this theoretical relation is found to agree with the measured burden velocities of 9 laboratory small-scale blasts to a certain *** predict the burden velocity of a small-scale blast,a further study or modification to the relation is necessary by using more small-scale blasts in the future.

关键词： Burden velocity Rock blasting Kinetic energy Delay time Tunnelling Minin

Empirical equations between characteristic impedance and mechanical properties of rocks

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第5期12卷 975-983页

作者： zong-Xian zhang De-Feng Hou Adeyemi Aladejare Oulu Mining School University of OuluOulu90014Finland College of Resources and Safety Engineering China University of Mining and TechnologyBeijing100083China

Based on a great number of experimental data on various mechanical properties of rock in the literature,six empirical equations between the characteristic impedance(product of density and P-wave velocity)and mechanical properties of rock are *** properties include uniaxial compressive strength,tensile strength,shear strength,mode I fracture toughness,Young’s modulus,and Poisson’s *** empirical equations show that the values of the aforementioned properties increase with increase in characteristic *** also implies that the characteristic impedance of rock may be considered as an index to represent the main properties of *** this sense,it is possible to consider using characteristic impedance to classify rock masses for studies in the future.

关键词： Characteristic impedance Mechanical properties Rock mass Classification Strength

Viscosity prediction on iron-bearing slags during pyrometallurgical recycling: structure-based modeling of CaO-‘FeO’-MgO-Al_(2)O_(3)-SiO_(2) system and its subsystems

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Journal of Iron and Steel Research International 2021年第6期28卷 679-692页

作者： Guang-zong zhang Nan Wang Min Chen Yan-qing Cheng School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina Institute for Frontier Technologies of Low-Carbon Steelmaking Shenyang 110819LiaoningChina Liaoning Province Engineering Research Center for Technologies of Low-Carbon Steelmaking Shenyang 110819LiaoningChina

A structure-based modeling of the CaO-‘FeO’-MgO-Al_(2)O_(3)-SiO_(2) system and its subsystems was investigated based on iron extraction nickel slagaluminum *** optimization in the present model indicated that the coefficient of free O^(2-)in FeO,a_(O_(FeO)^(2-)),on the lengths of network linkage had the largest value and O_(FeO)^(2-)(free O^(2)-in FeO)had the largest *** coefficients of bridging oxygen(a_(Si-O-Al) and a_(Al-O-Al))were lower than those of nonbridging oxygen and free oxygen(O^(2-)).Viscosity prediction for the CaO-‘FeO’-(8 wt.%)MgO-Al_(2)O_(3)-SiO_(2) system was conducted at a fixed slag basicity,which indicated that the predicted viscosity changed monotonously with the FeO ***,the non-monotonous evolution with Al2O3 content reflected the amphoteric behavior of *** addition,the performances of the present model in predicting viscosity binary(‘FeO’-SiO_(2))to quinary(CaO-‘FeO’-MgO-Al_(2)O_(3)-SiO_(2))system were analyzed and a comparison with the established models was made.

关键词： Nickel slag Viscosity model Slag structure Iron-bearing slag CaO-FeO-MgO-Al_(2)O_(3)-SiO_(2)system

Nicotine enhances migration and invasion of human esophageal squamous carcinoma cells which is inhibited by nimesulide

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World Journal of Gastroenterology 2009年第20期15卷 2500-2505页

作者： Ye zong Shu-Tian zhang Sheng-Tao Zhu Department of Gastroenterology Beijing Friendship Hospital Affiliated to the Capital Medical University Beijing Digestive Disease Center Beijing 100050 China

AIM： To study the effect of nicotine on the migration and invasion of human esophageal squamous carcinoma cells and to investigate whether nimesulide can inhibit the effect of ***： The esophageal squamous carcinoma cell line （TE-13） was treated with different concentrations of nicotine （100 μg/mL and 200 μg/mL） or 200 μg/mL nicotine plus 100 μmol/L nimesulide. Cell migration and invasion were measured using migration and invasion chamber systems. COX-2 expression was determined by Western blotting. Matrix metalloproteinase-2 （MMP-2） was analyzed by zymography and ***： Nicotine （100 μg/mL, 200 μg/mL） enhanced TE-13 cells migration and invasion, and increased the protein expression of COX-2 and the activity of MMP-2. Nicotine （200 μ/mL） stimulated TE-13 cells migration and invasion which were partly blocked by nimesulide. This was associated with decreased protein expression of COX-2 and decreased activity and protein expression of MMP-2. CONCLUSION： Nicotine enhances the migration and invasion of the esophageal squamous carcinoma cell line, and nimesulide partly blocks the effect ofnicotine-enhanced esophageal squamous carcinoma cell migration and invasion.

关键词： Carcinoma Cyclooxygenase 2 inhibitors Esophagus Nicotine Squamous cell