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略谈货币的中进制理论及其在实践中的若干应用
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作者 朱世浩 《湖北财经高等专科学校学报》 2009年第2期49-57,共9页
我国现行货币面额在满一元而不足十元时,分别有一元券、二元券和五元券三种;在十元以上而不满百元,一角以上而不满一元或一分以上而不满一角时其面额的配置均和元位券相似。为了叙述简单,我们把这种面额配置制度简称"1、2、5"... 我国现行货币面额在满一元而不足十元时,分别有一元券、二元券和五元券三种;在十元以上而不满百元,一角以上而不满一元或一分以上而不满一角时其面额的配置均和元位券相似。为了叙述简单,我们把这种面额配置制度简称"1、2、5"制,仿此简称办法,货币的面额配置制度还有"1、2、3"制和"1、2、4"制",1、3、4"制"、1、3、5"制和"1、4、5"制,总计共有六种面额配置制度。"1、3、4"制是最好的配置方案,在劳力和军力调配的应用中具有优越性。在军品民品计量包装上,采用"1、3"制对提高军运民运工作效率大有裨益。采用"1、3"制和"1、4"制两种配搭方案,就产生了五珠三升算盘和五珠四升算盘,此两种算盘和传统的一、四珠算盘,一、五珠算盘,二、五珠算盘比较,具有压倒的优势,将算盘改为三升或四升算盘将为珠算计算高数化提供无可置疑的利器。这一改革无疑是珠算改革的一个里程碑。 展开更多
关键词 货币面额 搭配 二元券 五元券 三元券 四元券 “1 2 5”制 “1 3 4”制 调配 军力 劳力 概率相等 战机 舰艇 军品 民品 计量包装 传输活动 高数数值计算 书面计算程序 算具 教具 学具 字母 三升算盘 四升算盘 二升算盘 五升算盘
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Synthesis and characterization of an unusual snowflake-shaped ZSM-5 zeolite with high catalytic performance in the methanol to olefin reaction 被引量:15
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作者 李静 刘粟侥 +3 位作者 张怀科 吕恩静 任鹏举 任杰 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第2期308-315,共8页
The ZSM-5 zeolite with an unusual snowflake-shaped morphology was hydrothermally synthesized for the first time,and compared with common ellipsoidal and boat-like shaped samples.These samples were characterized by N2 ... The ZSM-5 zeolite with an unusual snowflake-shaped morphology was hydrothermally synthesized for the first time,and compared with common ellipsoidal and boat-like shaped samples.These samples were characterized by N2 adsorption-desorption,X-ray fluorescence spectroscopy,scanning electron microscopy,X-ray diffraction,magic angle spinning nuclear magnetic resonance,temperature-programmed desorption of ammonia,and infrared spectroscopy of pyridine adsorption.The results suggest that the BET surface area and SiO2/Al2O3 ratio of these samples are similar,while the snowflake-shaped ZSM-5 zeolite possesses more of the(101) face,and distortion,dislocation,and asymmetry in the framework,resulting in a larger number of acid sites than the conventional samples.Catalysts for the methanol to olefin(MTO) reaction were prepared by loading Ca on the samples.The snowflake-shaped Ca/ZSM-5 zeolite exhibited excellent selectivity for total light olefin(72%) and propene(39%) in MTO.The catalytic performance influenced by the morphology can be mainly attributed to the snowflake-shaped ZSM-5 zeolite possessing distortion,dislocation,and asymmetry in the framework,and lower diffusion limitation than the conventional samples. 展开更多
关键词 ZSM-5 zeolite MODIFICATION Methanol to olefins
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A convenient synthesis of 1-alkyl-5-amino-6-phenylethyluracils as potential non-nucleoside HIV-1RT inhibitors
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作者 马小艳 程志坚 +4 位作者 陈艳丽 李阿敏 张志丽 王孝伟 刘俊义 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第4期281-284,共4页
1-Alkyl-5-amino-6-phenylethyluracils (1a, 1b) were synthesized as potential non-nucleoside HIV-1RT inhibitors. A convenient synthetic procedure was developed for the preparation of 1-alkyl-5-amino or 5-aminosubstitu... 1-Alkyl-5-amino-6-phenylethyluracils (1a, 1b) were synthesized as potential non-nucleoside HIV-1RT inhibitors. A convenient synthetic procedure was developed for the preparation of 1-alkyl-5-amino or 5-aminosubstituted-6-phenylethyluracils, which were synthesized in three or four steps from 6-methyluracil in good yield. The development of a one-pot reaction that simultaneously removed the benzyl protection group and reduced the nitro group greatly improved the yield of the synthesis. Compounds 1a and 1b are analogs of MKC-442, which is an efficient inhibitor of HIV-1 reverse transcriptase, 1a and 1b were tested for their inhibition of HIV-1RT, and moderate activity was found for 1a. 展开更多
关键词 HIV-1 reverse transcriptase 1-Alkyl-5-amino-6-phenylethyluracils Uracil derivatives
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5-methyl-1H-benzotriazole as potential corrosion inhibitor for electrochemical-mechanical planarization of copper 被引量:1
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作者 边燕飞 翟文杰 朱宝全 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第8期2431-2438,共8页
According to the electrochemical analysis, the corrosion inhibition efficiency of 5-methyl-lH-benzotriazole (m-BTA) is higher than that of benzotrizaole (BTA). The inhibition capability of the m-BTA passive film f... According to the electrochemical analysis, the corrosion inhibition efficiency of 5-methyl-lH-benzotriazole (m-BTA) is higher than that of benzotrizaole (BTA). The inhibition capability of the m-BTA passive film formed in hydroxyethylidenediphosphonic acid (HEDP) electrolyte containing both m-BTA and chloride ions is superior to that formed in m-BTA-alone electrolyte, even at a high anodic potential. The results of electrical impedance spectroscopy, nano-scratch experiments and energy dispersive analysis of X-ray (EDAX) indicate that the enhancement of m-BTA inhibition capability may be due to the increasing thickness of passive film. Furthermore, X-ray photoelectron spectrometry (XPS) analysis indicates that the increase in passive film thickness can be attributed to the incorporation of C1 into the m-BTA passive film and the formation of [Cu(I)CI(rn-BTA)], polymer film on Cu surface. Therefore, the introduction of C1- into m-BTA-containing HEDP electrolyte is effective to enhance the passivation capability of m-BTA passive film, thus extending the operating potential window. 展开更多
关键词 electrochemical-mechanical planarization 5-methyl-lH-benzotriazole corrosion inhibitor chloride ion
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External surface modification of as-made ZSM-5 and their catalytic performance in the methanol to propylene reaction 被引量:5
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作者 Xuebin Zhao Yang Hong +6 位作者 Linying Wang Dong Fan Nana Yan Xiaona Liu Peng Tian Xinwen Guo Zhongmin Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第8期1418-1426,共9页
Post-synthetic treatment of high-silica as-made ZSM-5 with organic template in the micropores was explored to reduce/remove the external surface acid density of ZSM-5. It is found that Na_2H_2 EDTA treatment can selec... Post-synthetic treatment of high-silica as-made ZSM-5 with organic template in the micropores was explored to reduce/remove the external surface acid density of ZSM-5. It is found that Na_2H_2 EDTA treatment can selectively remove the surface Al atoms, but generates new acid sites(likely silanol nests) on the external surface. H_3PO_4 treatment is unable to remove surface Al atoms, while small amount of P is left on the external surface, which effectively decreases the acid density. The catalytic performance of the resultant materials is evaluated in the methanol conversion reaction. H_3PO_4 treatment can effectively improve both the catalytic lifetime and the stability of propene selectivity.This occurs due to a combination of the increased tolerance to the external coke deposition and the depressed coking rate(reduced side reactions). Na_2H_2 EDTA treatment only prolongs the catalytic lifetime, resulting from the improved tolerance to the external coke deposition. Under the optimized H_3PO_4 treatment condition, the resultant ZSM-5 gives a catalytic lifetime of about 1.5 times longer than the precursor. Moreover, the propene selectivity is improved, showing a slight increasing trend until the deactivation. 展开更多
关键词 Methanol topropene ZSM‐5 zeolite Modification Phosphoricacid Ethylenediamine tetraaceticacid
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Anti-hepatocarcinoma effects of 5-fluorouracil encapsulated by galactosylceramide liposomes in vivo and in vitro 被引量:8
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作者 YongJin JunLi Long-FuRong Yuan-HaiLi LinGuo Shu-YunXu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第17期2643-2646,共4页
AIM:To study the anti-hepatocarcinoma effects of 5-fluorouracil (5-Fu) encapsulated by galactosylceramide liposomes (5-Fu-GCL) in vivo and in vitro. METHODS: Tumor-bearing animal model and HepA cell line were respecti... AIM:To study the anti-hepatocarcinoma effects of 5-fluorouracil (5-Fu) encapsulated by galactosylceramide liposomes (5-Fu-GCL) in vivo and in vitro. METHODS: Tumor-bearing animal model and HepA cell line were respectively adopted to evaluate the anti-tumor effects of 5-Fu-GCL in vivo and in vitro. Tumor cell growth inhibition effects of 5-Fu-GCL in vitro were assessed by cell viability assay and MTT assay. In vivo experiment, the inhibitory effects on tumor growth were evaluated by tumor inhibition rate and animal survival days. High performance liquid chromatography was used to detect the concentration-time course of 5-Fu-GCL in intracellular fluid in vitro and the distribution of 5-Fu-GCL in liver tumor tissues in vivo. Apoptosis and cell cycle of tumor cells were demonstrated by flow cytometry. RESULTS: In vitro experiment, 5-Fu-GCL (6.25-100 μmol/L) and free 5-Fu significantly inhibited HepA cell growth. Furthermore, IC50 of 5-Fu-GCL (34.5 μmol/L) was lower than that of free 5-Fu (51.2 μmol/L). In vivo experiment, 5-Fu-GCL (20, 40, 80 mg/kg) significantly suppressed the tumor growth in HepA bearing mice model. Compared with free 5-Fu, the area under curve of 5-Fu-GCL in intracellular fluid increased 2.6 times. Similarly, the distribution of 5-Fu-GCL in liver tumor tissues was significantly higher than that of free 5-Fu. After being treated with 5-Fu-GCL, the apoptotic rate and the proportion of HepA cells in the S phase increased, while the proportion in the G0/G1 and G2/M phases decreased. CONCLUSION: 5-Fu-GCL appears to have anti-hepatocarcinoma effects and its drug action is better than free 5-Fu. Its mechanism is partly related to increased drug concentrations in intracellular fluid and liver tumor tissues, enhanced tumor cell apoptotic rate and arrest of cell cycle in S phase. 展开更多
关键词 5-FLUOROURACIL GALACTOSYLCERAMIDE LIPOSOME Anti-hepatocarcinoma
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Changing the balance of the MTO reaction dual-cycle mechanism: Reactions over ZSM-5 with varying contact times 被引量:7
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作者 张默之 徐舒涛 +5 位作者 魏迎旭 李金哲 王金棒 张雯娜 高树树 刘中民 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1413-1422,共10页
The methanol to olefins (MTO) reaction was performed over ZSM‐5 zeolite at 300℃ under various methanol weight hourly space velocity (WHSV) values. During these trials, the catalytic perfor‐mance was assessed, i... The methanol to olefins (MTO) reaction was performed over ZSM‐5 zeolite at 300℃ under various methanol weight hourly space velocity (WHSV) values. During these trials, the catalytic perfor‐mance was assessed, in addition to the formation and function of organic compounds retained in the zeolite. Analysis of reaction effluents and confined organics demonstrated a dual‐cycle reaction mechanism when employing ZSM‐5. The extent of the hydrogen transfer reaction, a secondary reac‐tion in the MTO process, varied as the catalyst‐methanol contact time was changed. In addition, 12C/13C‐methanol switch experiments indicated a relationship between the dual‐cycle mechanism and the extent of the hydrogen transfer reaction. Reactions employing a low methanol WHSV in conjunction with a long contact time favored the hydrogen transfer reaction to give alkene products and promoted the generation and accumulation of retained organic species, such as aromatics and methylcyclopentadienes, which enhance the aromatic cycle. When using higher WHSV values, the reduced contact times lessened the extent of the hydrogen transfer reaction and limited the genera‐tion of methylcyclopentadienes and aromatic species. This suppressed the aromatic cycle, such that the alkene cycle became the dominant route during the MTO reaction. 展开更多
关键词 Methanol to olefins Dual-cycle mechanism ZSM-5 Contact time Hydrogen transfer reaction
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The 5'-flanking cis-acting elements of the human ε-globin gene associates with the nuclear matrix and binds to the nuclear matrix proteins
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作者 YANZHIJIANG RUOLANQIAN 《Cell Research》 SCIE CAS CSCD 1998年第3期209-218,共10页
The nucleax mains attachment regions(MARs) and the binding nuclear matrix proteins in the 5’-flalildng cisacting elements of the humanε-globin gene have been examined. Using in vitro DNA-matrix binding assay,it has ... The nucleax mains attachment regions(MARs) and the binding nuclear matrix proteins in the 5’-flalildng cisacting elements of the humanε-globin gene have been examined. Using in vitro DNA-matrix binding assay,it has been shown that the positive stage-specific regulatory element (ε-PREII, -446bp-419bp) upstream of this gene could specifically associate with the nuclear matrix from K562 cells, indicating thatε-PREII mad be an erythroidspecilic facultstive MAR. In gel mobility shift assay and Southwestern blotting assal an eothroid-specific nuclear matrix protein (ε-NMPk) in K562 cells has been revealed to bind to this positive regulatory element (E-PREII). Furthermore, we demonstrated that the silencer (-392hp -177bp) uP8tream of the humanε-globin gene could associate with the nuclear matrices from K562, HEL and Raji cells. In addition, the nucleax matrix proteins prepared from these three cell lines could also bind to this silencer, suggesting that this silencer element linght be a constitutive nuclear mains attachment region (constitutive MAR). Our results demonstrated that the nucleax madrid and nuclear mains proteins lxilght play an important role in the regulation of the human 5-globin gene expression. 展开更多
关键词 Human ε-globin gene nuclear matrix attachment regions nuclear matrix proteins K562 cells
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Forward Position Analysis of 5-DOF Parallel Mechanism 被引量:1
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作者 齐明 梅江平 《Transactions of Tianjin University》 EI CAS 2006年第6期434-437,共4页
A systematic method for the forward kinematics of a five degrees of freedom (5-DOF) parallel mechanism with the legs' topology 4-UPS/UPU, is developed. Such mechanism is composed of a movable platform connected to ... A systematic method for the forward kinematics of a five degrees of freedom (5-DOF) parallel mechanism with the legs' topology 4-UPS/UPU, is developed. Such mechanism is composed of a movable platform connected to the base by four identical 6-DOF active limbs plus one active limb with its DOF being exactly the same as the specified DQF of the movable platform. Three translational and two rotational DOFs can be achieved. Firstly, a set of polynomial equations of forward position analysis is formulated based on the architecture of the mechanism. Then the system of equations is degraded from five-dimensional to three-dimensional by means of analytic elimination. Method of least squares and Gauss-Newton algorithm are used to construct the objective function and to solve it, respectively. Example shows that through 4-time iteration within 16 ms the ohjective, function converaes to the provided error tolerance. 10^-4. 展开更多
关键词 parallel machines forward kinematics 5-DOF numerical analysis
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Catalytic roles of the acid sites in different pore channels of H‐ZSM‐5 zeolite for methanol‐to‐olefins conversion 被引量:10
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作者 Sen Wang Zhikai Li +4 位作者 Zhangfeng Qin Mei Dong Junfen Li Weibin Fan Jianguo Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第7期1126-1136,共11页
H‐ZSM‐5 zeolite is a typical catalyst for methanol‐to‐olefins(MTO)conversion.Although the performance of zeolite catalysts for MTO conversion is related to the actual location of acid sites in the zeolite framewor... H‐ZSM‐5 zeolite is a typical catalyst for methanol‐to‐olefins(MTO)conversion.Although the performance of zeolite catalysts for MTO conversion is related to the actual location of acid sites in the zeolite framework,the catalytic roles of the acid sites in different pore channels of the H‐ZSM‐5 zeolite are not well understood.In this study,the MTO reaction network,involving the aromatic cycle,alkene cycle,and aromatization process,and also the diffusion behavior of methanol feedstock and olefin and aromatic products at different acid sites in the straight channel,sinusoidal channel,and intersection cavity of H‐ZSM‐5 zeolite was comparatively investigated using density functional theory calculations and molecular dynamic simulations.The results indicated that the aromatic cycle and aromatization process occurred preferentially at the acid sites in the intersection cavities with a much lower energy barrier than that at the acid sites in the straight and sinusoidal channels.In contrast,the formation of polymethylbenzenes was significantly suppressed at the acid sites in the sinusoidal and straight channels,whereas the alkene cycle can occur at all three types of acid sites with similar energy barriers and probabilities.Consequently,the catalytic performance of H‐ZSM‐5 zeolite for MTO conversion,including activity and product selectivity,can be regulated properly through the purposive alteration of the acid site distribution,viz.,the location of Al in the zeolite framework.This study helps to elucidate the relation between the catalytic performance of different acid sites in the H‐ZSM‐5 zeolite framework for MTO conversion,which should greatly benefit the design of efficient catalyst for methanol conversion. 展开更多
关键词 Methanol‐to‐olefins H‐ZSM‐5 zeolite Acid site distribution Density functional theory calculation Molecular dynamic simulation
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5-Fluorouracil-loaded Self-assembled pH-sensitive Nanoparticles as Novel Drug Carrier for Treatment of Malignant Tumors 被引量:7
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作者 刘亮 晋平 +2 位作者 程明 张国亮 张凤宝 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第3期377-382,共6页
In order to improve the cancer-targeting and selective activity of antineoplastic agent [5-fluorouracil (5-FU)], a novel pH-responsive drug delivery system [pullulan acetate/sulfonamide (PA/SDM) conjugate] was syn... In order to improve the cancer-targeting and selective activity of antineoplastic agent [5-fluorouracil (5-FU)], a novel pH-responsive drug delivery system [pullulan acetate/sulfonamide (PA/SDM) conjugate] was synthesized by a diafiltration method. Sulfonamide was grafted to the hydrophobicaUy modified pullulan acetate to enhance the pH sensitivity for better cancer-targeting delivery. 5-FU was loaded into the self-assembled nanoparticles by the same method. The drug-loaded self-assembled nanoparticles were successfully obtained and characterized in terms of particle size, morphology and drug loading and release profile at various pHs. The results showed that the mean diameter of the self-assembled particles was approximately 100nm, with uniform size and good spherical morphology. The nanoparticles showed good stability at pH 7.4, which is equal to that of the normal body fluid, but shrank and aggregated below pH 6.8, which is close to the pH with tumors. The loading efficiency and concentration of released 5-FU was monitored at 269 nm on the UVNis spectrophotometer. The release profile was heavily pH-dependent around phvsiological pH, and the release rate was significantly enhanced under pH of 6.8. 展开更多
关键词 5-FLUOROURACIL self-assembled nanoparticles pH sensitivity drug delivery PULLULAN
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INHIBITORY EFFECTS OF ADENOSINE 5' -TRIPHOSPHATE ON COCHLEAR FUNCTION OF GUINEA PIG
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作者 杨军 李吉平 +3 位作者 钱敏飞 徐秀玲 王家东 丁大连 《Journal of Shanghai Second Medical University(Foreign Language Edition)》 2005年第1期1-5,共5页
Objective To study effects of adenosine 5’-triphosphate (ATP) on cochlear function of guineapig. Methods After perfusion of ATP into perilymphatic spaces of the guinea pig cochlea, summating potential(SP) , cochlear ... Objective To study effects of adenosine 5’-triphosphate (ATP) on cochlear function of guineapig. Methods After perfusion of ATP into perilymphatic spaces of the guinea pig cochlea, summating potential(SP) , cochlear microphonic ( CM) , auditory nerve compound action potential ( CAP) , distortion product otoa-coustic emission (DPOAE) and auditory brainstem response (ABR) were measured. Results The resultsshowed concentration-dependent effect of ATP on the response alterations of bioelectric activity in cochlea. Adminis-tration of Immol/L ATP caused an increase both in the amplitude of the SP and in the threshold of ABR, a decreasein amplitude of the CAP and DPOAE. In addition, response alterations of the CAP and DPOAE showed in an inten-sity- and frequency-dependent manner, respectively. At levels of 20 - 70dB nHL sound intensity, lmmol/L ATPcaused a significant decrease in the CAP amplitude, while at moderate and high frequency ranges of 2 -8kHz it re-duced DPOAE amplitude significantly. 330μmol/L ATP also increased the threshold of ABR. Conclusion ATPthrough perilymphatic perfusion could inhibit cochlear function of guinea pig. 展开更多
关键词 ATP perilymphatic perfusion cochlear function bioelectric activity in cochlea
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Proteins binding to the 5'-flanking regulatory elements of the human β-globin gene
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作者 CHENZHIGANG YADICHEN 《Cell Research》 SCIE CAS CSCD 1993年第2期195-202,共8页
The binding of nuclear proteins prepared from mouse erythroid tissue in different developmental stages to the 5'-flanking regulatory elements of human β-globin gene, two negative control regions(NCR1,-610 to -490... The binding of nuclear proteins prepared from mouse erythroid tissue in different developmental stages to the 5'-flanking regulatory elements of human β-globin gene, two negative control regions(NCR1,-610 to -490 bp;NCR2, -338 to-233bp), was identified.Two stage specific protein factors corresponding to embryonic and fetal stages were found to be capable of binding to NCR2.These data provided evidence that the cis acting elements of the 5'-flanking region might be involved in the developmental control of β-globin gene and NCR2 might be responsible in part for the silence of β-globin gene in the embryonic and fetal stages. 展开更多
关键词 human β-globin gene negative control region stage specific factor.
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考虑既有船坞的深基坑工程设计 被引量:1
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作者 殷建国 李萌玉 +2 位作者 张克胜 郁志伟 宋卓华 《港工技术》 2023年第1期43-47,共5页
本工程地处城市中心区复杂环境,既有船坞位于基坑范围内,这种情况的审计工程尚属国内先例。本文针对既有船坞对基坑工程的影响,介绍了基坑支护设计,如既有船坞主体结构及下部桩基障碍物清除、围护墙在既有船坞结构与工程桩重叠时的实施... 本工程地处城市中心区复杂环境,既有船坞位于基坑范围内,这种情况的审计工程尚属国内先例。本文针对既有船坞对基坑工程的影响,介绍了基坑支护设计,如既有船坞主体结构及下部桩基障碍物清除、围护墙在既有船坞结构与工程桩重叠时的实施、船坞底板下工程桩拔出及承压水层突涌风险控制、船坞底板下桩基遭遇实际桩位同图纸偏差时的风险控制、既有船坞结构与支护结构衔接等。实践表明,相应的设计技术有效地保证了工程工期、基坑安全及周边环境的安全。 展开更多
关键词 深基坑 船坞 清障 基坑支护设计
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PLANNING METHOD OF TOOL ORIENTATION IN FIVE-AXIS NC MACHINING
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作者 姬俊锋 周来水 +1 位作者 安鲁陵 张森棠 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第2期83-88,共6页
The planning method of tool orientation in the five-axis NC machining is studied. The problem of the existing method is analyzed and a new method for generating the global smoothing tool orientation is proposed by int... The planning method of tool orientation in the five-axis NC machining is studied. The problem of the existing method is analyzed and a new method for generating the global smoothing tool orientation is proposed by introducing the key frame idea in the animation-making. According to the feature of the part, several key tool orientations are set without interference between the tool and the part. Then, these key tool orientations are inter- polated by the spline function. By mapping the surface parameter to the spline parameter, the spline function value is obtained and taken as the tool orientation when generating the CL file. The machining result shows that the proposed method realizes the global smoothing of the tool orientation and the continuity of the rotational speed and the rotational acceleration. It also avoids the shake of the machine tool and improves the machining quality. 展开更多
关键词 computer aided mamufacturing NC machining TOOLS FIVE-AXIS
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Methanol-to-propylene process: Perspective of the most important catalysts and their behavior 被引量:16
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作者 M.Khanmohammadi Sh.Amani +1 位作者 A.Bagheri Garmarudi A.Niaeib 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第3期325-339,共15页
The methanol-to-propylene (MTP) process is a route of methanol conversion to hydrocarbons, which is in high demand because of limited oil resources. The present paper discusses the effect of catalyst structure on th... The methanol-to-propylene (MTP) process is a route of methanol conversion to hydrocarbons, which is in high demand because of limited oil resources. The present paper discusses the effect of catalyst structure on the MTP process conditions, and the role of different zeolite factors, such as acidity, crystal size, mesoporosity, and topology, on the activity and selectivity of the MTP reaction. 展开更多
关键词 Methanol-to-propylene process ZSM-5 zeolite CATALYSIS
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Synthesis of dutasteride 被引量:1
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作者 张奎平 雷小平 《Journal of Chinese Pharmaceutical Sciences》 CAS 2007年第3期233-235,共3页
Aim To synthesize dutasteride. Methods The target compound was synthesized from pregnenolol via eight steps, including esterification, oxidation, hydrolysis, then oxidative ring-opening, cyclization, reduction, oxidiz... Aim To synthesize dutasteride. Methods The target compound was synthesized from pregnenolol via eight steps, including esterification, oxidation, hydrolysis, then oxidative ring-opening, cyclization, reduction, oxidization and finally acylation. Results The structure of the target molecule was identified by ^1H NMR, ^13C NMR and element analysis. The overall yield was 31.5%. Conclusion The effects of different reaction conditions on the yield of product in each step have been investigated and the optimal reaction conditions have been established. 展开更多
关键词 Steroid hormones Dutastefide Pregnenolol Inhibition of 5α-reductase
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GABA transporter 1 transcriptional starting site exhibiting tissue specific difference 被引量:4
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作者 JinXP HuangF 《Cell Research》 SCIE CAS CSCD 2001年第2期161-163,共3页
GABA transporter 1(GAT1) takes important roles in multiple physiological processes through the uptake and release of GABA, but the regulation of GAT1 gene expression in different tissues is rarely known. To address th... GABA transporter 1(GAT1) takes important roles in multiple physiological processes through the uptake and release of GABA, but the regulation of GAT1 gene expression in different tissues is rarely known. To address the question, first, 5’ Rapid amplification of cDNA end (RACE) was used to determine GAT1 transcriptional starting sites in neonatal mouse cerebral cortex and intestine, adult mouse brain and adult rat testis. The products of 5’RACE were confirmed by DNA sequencing. We found that the transcript of GAT1 in neonatal mouse cerebral cortex and adult mouse brain starts at the same site (inside of exon 1), while in mouse intestine, GAT1 starts transcription in intron 1, and in rat testis, the transcript of GAT1 has an additional untranslation exon to the 5’ direction. 展开更多
关键词 Membrane Transport Proteins Organic Anion Transporters Aging ANIMALS Animals Newborn Base Sequence Brain Carrier Proteins DNA Complementary EXONS GABA Plasma Membrane Transport Proteins Gene Expression Regulation INTESTINES INTRONS Male Membrane Proteins MICE Mice Inbred BALB C Molecular Sequence Data Nucleic Acid Amplification Techniques Research Support Non-U.S. Gov't Testis Transcription Genetic
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Effects of granulocyte-colony stimulating factor on peritoneal defense mechanisms and bacterial translocation after administration of systemic chemotherapy in rats 被引量:1
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作者 Celal Cerci Cagri Ergin +4 位作者 Erol Eroglu Canan Agalar Fatih Agalar Sureyya Cerci Mahmut Bulbul 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第18期2596-2599,共4页
AIM: To investigate the effects of granulocyte-colony stimulating factor (G-CSF) on peritoneal defense mechanisms and bacterial translocation after systemic 5-Fluorouracil (5-FU) administration. METHODS: Thirty ... AIM: To investigate the effects of granulocyte-colony stimulating factor (G-CSF) on peritoneal defense mechanisms and bacterial translocation after systemic 5-Fluorouracil (5-FU) administration. METHODS: Thirty Wistar albino rats were divided into three groups; the control, 5-FU and 5-FU + G-CSF groups. We measured bactericidal activity of the peritoneal fluid, phagocytic activity of polymorphonuclear leucocytes in the peritoneal fluid, total peritoneal cell counts and cell types of peritoneal washing fluid. Bacterial translocation was quantified by mesenteric lymph node, liver and spleen tissue cultures. RESULTS: Systemic 5-FU reduced total peritoneal cell counts, neutrophUs and macrophage numbers. It also altered bactericidal activity of the peritoneal fluid and phagocytic activity of polymorphonuclear leucocytes in the peritoneal fluid. 5-FU also caused significant increase in frequencies of bacterial translocation at the liver and mesenteric lymph nodes. G-CSF decreased bacterial translocation, it significantly enhanced bactericidal activity of the peritoneal fluid and phagocytic activity of polymorphonuclear leucocytes in the peritoneal fluid. It also increased total peritoneal cell counts, neutrophils and macrophage numbers. CONCLUSION: Systemic 5-FU administration caused bacterial translocation, decreased the bactericidal activity of peritoneal fluid and phagocytic activity of polymorphonuclear leucocytes in the peritoneal fluid. G-CSF increased both bactericidal activity of the peritoneal fluid and phagocytic activity of polymorphonuclear leucocytes in the peritoneal fluid, and prevented the bacterial translocation. We conclude that intraperitoneal GCSF administration protects the effects of systemic 5-FU on peritoneal defense mechanisms. 展开更多
关键词 Granulocyte-colony stimulating factor 5-FLUOROURACIL Bacterial translocation Peritoneal defensemechanisms
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Effect of 5-HMF on protection of hydrogen peroxide-induced injury in human umbilical vein endothelial cells 被引量:3
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作者 沈亚芬 吴鑫 +1 位作者 曹岗 蔡皓 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2015年第3期164-168,共5页
The protective effect of 5-hydroxymethylfurfural(5-HMF) against hydrogen peroxide(H2O2)-induced injured in human umbilical vein endothelial cells(HUVECs) was examined. Treatment of HUVECs with 5-HMF significantl... The protective effect of 5-hydroxymethylfurfural(5-HMF) against hydrogen peroxide(H2O2)-induced injured in human umbilical vein endothelial cells(HUVECs) was examined. Treatment of HUVECs with 5-HMF significantly increased their viability, decreased cell apoptosis induced by H2O2, accompanied by the decreased nitric oxide level. Western blotting analysis demonstrated that Bcl-2 expression was increased whereas Caspase-3 and NF-κB expression was decreased in 5-HMF groups. In conclusion, the results showed that 5-HMF could prevent endothelial dysfunction and related complications caused by oxidative stress. 展开更多
关键词 Processed Fructus Corni 5-HYDROXYMETHYLFURFURAL Nitric oxide Apoptosis Hydrogen peroxide
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