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<正>(接上期)(3)耐油同步带自上世纪60年代,美国通用公司首次将同步带用于新开发的顶制式凸轮(OHC)发动机替代原来使用的滚珠链条以来,由于同步带具有同步性能好、噪音小、无需润滑、重量轻、成本低和 相似文献
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基于Repast平台的SARS传播仿真建模研究 总被引：4，自引：0，他引：4
通过引入基于主体的建模思路和方法,根据易于描述的微观个体行为,利用Repast仿真建模平台对SARS的传播过程进行模拟,从而研究SARS传播宏观层面的规律,并根据謇验结果提出了疫情防控的策略和措施.本文初步构造了SARS传播的主体模型,定义了主体的状态转换方式以及主体之间的行为规则,并实现了一个可用于模拟SARS传播过程的简单的仿真建模框架,通过可动态扩展的规则设定、模型参数调节,为研究SARS传播提供了方便的模拟环境. 相似文献
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紫苏籽油是一种富含多不饱和脂肪酸的食用植物油,从食药同源植物紫苏成熟的种子中获得。紫苏籽含有脂肪、蛋白质、脂肪酸、甾醇、脂溶性维生素等多种营养物质,其主要成分是α-亚麻酸。紫苏籽油是迄今为止发现的草本植物种子油中α-亚麻酸含量最高的食用油,在医药和食品加工方面具有很高的利用价值。通过对国内外紫苏籽油研究进展综述,本文总结了紫苏籽油的功效作用、理化性质、营养成分及检测方法,为后续紫苏籽油及其副产物的开发利用提供参考依据。 相似文献
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The upper Cretaceous Sarvak reservoir in the Azadegan oil field of southwest Iran has its oil–water contact nearly horizontal from the north to the center and dips steeply from the center to the south.The purpose of this paper is to interpret this abnormal reservoir feature by examining the accumulation elements,characteristics,and evolution based on the 3D seismic,coring,and well logging data.Generally,in the field,the Sarvak reservoir is massive and vertically heterogeneous,and impermeable interlayers are rare.The distribution of petrophysical properties is mainly dominated by the depositional paleogeomorphology and degrades from north to south laterally.The source is the lower Cretaceous Kazhdumi Formation of the eastern Dezful sag,and the seal is the muddy dense limestone of the Cenozoic Gurpi and Pebdeh Formations.Combined with the trap evolution,the accumulation evolution can be summarized as follows: the Sarvak play became a paleo-anticlinal trap in the Alpine tectonic activity after the late Cretaceous(96 Ma) and then was relatively peaceful in the later long geologic period.The Kazhdumi Formation entered in the oil window at the early Miocene(12–10 Ma) and charged the Sarvak bed,thus forming the paleo-reservoir.Impacted by the ZagrosOrogeny,the paleo-reservoir trap experienced a strong secondary deformation in the late Pliocene(4 Ma),which shows as the paleo-trap shrank dramatically and the prelow southern area uplifted and formed a new secondary anticline trap,hence evolving to the current two structural highs with the south point(secondary trap) higher than the north(paleo-trap).The trap deformation broke the paleoreservoir kinetic equilibrium and caused the secondary reservoir adjustment.The upper seal prevented vertical oil dissipation,and thus,the migration is mainly in interior Sarvak bed from northern paleo-reservoir to the southern secondary trap.The strong reservoir heterogeneity and the degradation trend of reservoir properties along migration path(north to south) made the reservoir readjustment extremely slow,plus the short and insufficient re-balance time,making the Sarvak form an ‘‘unsteady reservoir'which is still in the readjustment process and has not reached a new balance state.The current abnormal oil–water contact versus the trap evolutionary trend indicates the secondary readjustment is still in its early stage and has only impacted part of paleo-reservoir.Consequently,not all of the reservoir is dominated by the current structure,and some parts still stay at the paleo-reservoir form.From the overview above,we suggest the following for the future development: In the northern structural high,the field development should be focused on the original paleoreservoir zone.In the southern structural high,compared with the secondary reservoir of the Sarvak with the tilted oil–water contact and huge geologic uncertainty,the lower sandstone reservoirs are more reliable and could be developed first,and then the deployment optimized of the upper Sarvak after obtaining sufficient geological data.By the hints of the similar reservoir characteristics and tectonic inheritance with Sarvak,the lower Cretaceous Fahliyancarbonate reservoir is also proved to be an unsteady reservoir with a tilted oil–water contact. 相似文献
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Yi-Zhen Zheng Jingxuan Cui Yung-Lin Wang Szu-Jo Huang En-Chi Lin Sheng-Cih Huang Jeffrey D. Rudolf Xiaohui Yan Chin-Yuan Chang 《Chembiochem : a European journal of chemical biology》2022,23(12):e202200186
Human bleomycin hydrolase (hBH) catalyzes deamidation of the anticancer drug bleomycins (BLM). This enzyme is involved in BLM detoxification and drug resistance. Herein, we report the putative BLM-binding site and catalytic mechanism of hBH. The crystal structures and biochemical studies suggest that hBH cleaves its C-terminal residue without significant preference for the type of amino acid, and therefore can accordingly accommodate the β-aminoalanine amide moiety of BLM for deamidation. Interestingly, hBH is capable of switching from a cysteine protease to a serine protease that is unable to cleave the secondary amide of hBH C-terminus but reacts with the primary amide of BLMs. 相似文献
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The aim of this paper was to reveal the relationship between the interaction energy of benzodifuranone dyes and dyeing performance indices such as dyeing temperature and colour fastness. Dimer models of benzene–benzene, benzodifuranone–benzene, and benzodifuranone–benzodifuranone configuration were set up, and geometry optimisation and interaction energy were calculated using a density functional theory ωB97XD, 6-311G++ (d, p) basis set. The calculation results showed that the benzodifuranone molecule had better coplanarity. The molecular interaction energy of benzene–benzene, benzodifuranone–benzene, and benzodifuranone–benzodifuranone rings decreased at first, and then increased with growth in the distance between the rings, the lowest energy occurring at a distance of about 3.25–3.75 Å. The dispersion force affected the interaction energy of benzodifuranone–benzene rings most, while both dispersion force and electrostatic force influenced the interaction energy of benzodifuranone–benzodifuranone rings. These calculation and experimental results revealed that a greater energy was needed to destroy the dye–fibre and dye–dye interaction energy of benzodifuranone-based disperse dyes. 相似文献
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Jia-Ming Chang Jin-Yi Wu Shu-Hsin Chen Wen-Ying Chao Hsiang-Hao Chuang Kam-Hong Kam Pei-Wen Zhao Yi-Zhen Li Yu-Pei Yen Ying-Ray Lee 《International journal of molecular sciences》2021,22(18)
Lung cancer is one of the most common cancers and the leading cause of death in humans worldwide. Non-small-cell lung cancer (NSCLC) accounts for approximately 85% of lung cancer cases and is often diagnosed at a late stage. Among patients with NSCLC, 50% die within 1 year after diagnosis. Even with clinical intervention, the 5-year survival rate is only approximately 20%. Therefore, the development of an advanced therapeutic strategy or novel agent is urgently required for treating NSCLC. Berberine exerts therapeutic activity toward NSCLC; therefore, its activity as an antitumor agent needs to be explored further. In this study, three terpenylated-bromide derivatives of berberrubine were synthesized and their anti-NSCLC activities were evaluated. Each derivative had higher anti-NSCLCs activity than berberrubine and berberine. Among them, 9-O-gernylberberrubine bromide (B4) and 9-O-farnesylberberrubine bromide (B5) showed greater growth inhibition, cell-cycle regulation, in vitro tumorigenesis suppression, and tumor migration reduction. In addition, some degree of apoptosis and autophagic flux blocking was noted in the cells under B4 and B5 treatments. Our study demonstrates that the berberrubine derivatives, B4 and B5, exhibit impressive anti-NSCLC activities and have potential for use as chemotherapeutic agents against NSCLC. 相似文献
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系统研究了快速热退火对锌扩散的In0.53Ga0.47As/InP PIN探测器的影响.利用电化学电容电压和二次离子质谱技术分析了退火前后Zn和净受主的浓度分布,结果表明退火过程会影响杂质浓度,但不影响扩散深度.制备了不同退火条件的ln053Ga0.47As/InP PIN探测器.器件测试反映,未退火的探测器在260-300K具有更低的器件电容和更高的激活能.通过暗电流成分拟合对器件暗电流机制进行分析,未退火器件表现出更低的肖克利-里德-霍尔产生复合电流和扩散电流,因而室温下未退火器件具有更高的峰值探测率.为了制备高性能低掺杂吸收层结构的平面型InGaAs探测器,快速热退火是不必要的工艺. 相似文献
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目的 探讨章姬草莓果实的贮藏特性与油菜素甾醇(brassinosteroids, BRs)的关系。方法 以章姬草莓为供试材料, 以蒸馏水为对照, 通过不同浓度的BRs溶液(5、10、15 μmol/L)喷洒草莓果实, 观察BRs对其失重率、腐烂情况等贮藏品质的影响。结果 经过BRs处理章姬草莓果实后质量损失明显降低, 腐烂速度减缓, 特别是在10 μmol/L浓度喷洒下章姬草莓果实失重率、可溶性固形物和维生素C (vitamin C, VC)含量的损失均显著低于对照组。在第6 d时, 10 μmol/L BRs处理组章姬草莓果实比对照组的VC含量高1.8倍, 硬度高19.2%; 腐烂率、腐烂指数、丙二醛含量的增加量均显著低于对照组(P<0.05); 对照组比10 μmol/L BRs处理组章姬草莓果实丙二醛含量高1.27倍, 腐烂率高13%, 腐烂指数高20%。结论 10 μmol/L BRs喷洒下对延长章姬草莓果实的贮藏时间具有较好的效果。 相似文献