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通用电子记录存储与取证系统研究

信息安全与通信保密 2011年第8期9卷 44-46,49页

作者：龙毅宏罗盛唐志红刘旭北京天威诚信电子商务服务有限公司北京100088

对一种通用的电子记录存储与取证服务系统进行了研究。该系统通过数字签名,为电子记录提供作为有效证据所需的原发性、完整性和真实性证明,以及针对记录源发者的抗抵赖依据。该系统是通用的,因为它能通过对电子记录类的定义和描述,处理... 详细信息

对一种通用的电子记录存储与取证服务系统进行了研究。该系统通过数字签名,为电子记录提供作为有效证据所需的原发性、完整性和真实性证明,以及针对记录源发者的抗抵赖依据。该系统是通用的,因为它能通过对电子记录类的定义和描述,处理各种不同的记录,并能通过自定义的记录关系规则对记录进行关联搜索,以获取证据链。它可用于提供基于第三方的记录存储和取证服务以保证公平性。

关键词：电子记录电子证据取证数字签名时间戳

Purity of SiC powders fabricated by coat-mix

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International Journal of Minerals,Metallurgy and Materials 2009年第2期16卷 230-235页

作者： Li-min Shi hong-sheng Zhao Chun-he tang Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China

Silicon carbide powders were synthesized by the coat-mix process, with phenolic resin and silicon powders as starting materials. The effects of synthetic conditions, including sintering temperature and the molar ratio of resin-derived carbon to silicon on the composition and the purity of the resultant powders were investigated. The results show that a higher sintering temperature and an appropriate molar ratio of resin-derived carbon to silicon are favorable for producing high purity silicon carbide powders. It is found that the silicon carbide content increases slightly with increasing the sintering temperature during the solid-solid reaction. The temperature gradient plays an important role on this trend. When the sintering temperature is raised up to 1500℃, the formation of silicon earbide is based on the liquid-solid reaction, and high purity （99.8wt%） silicon carbide powders can easily be obtained. It can also be found that the optimum molar ratio of resin-derived carbon to silicon is 1：1.

关键词： silicon carbide powders coat-mix purity

Estimating and Mapping Extreme Ice Accretion Hazard and Load Due to Freezing Rain at Canadian Sites

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International Journal of Disaster Risk Science 2023年第1期14卷 127-142页

作者： Chao sheng Qian tang H.P.hong Department of Civil and Environmental Engineering University of Western OntarioLondonOntarioN6A 5B9Canada

The ice accretion load in Canadian structural design codes is developed based on an operational ice accretion prediction *** the present study,three models are employed to predict the ice accretion amount on a flat surface and horizontal wire at Canadian *** results confirm that the model used by Canadian practice for predicting ice accretion leads to a conservative estimate as compared to the remaining two *** results also indicate that the use of the Gumbel distribution for the annual maximum ice accretion is adequate for regions prone to ice accretion and that the lognormal distribution may be considered for regions with a moderate or negligible amount of ice *** of the ice accretion hazard at five selected Canadian sites are *** analysis of an equivalent wind speed that is concurrent with the iced wire is carried out,showing that the concurrent wind speed for the 50-year return period value of the annual maximum ice accretion amount is smaller than the 50-year return period value of the annual maximum wind *** is shown that the statistical characteristics of the annual maximum concurrent wind speed on iced wire differ from that of the annual maximum wind speed.

关键词： Canada Concurrent wind speed Hazard mapping Ice accretion Probabilistic analysis

Effects of Br^- and I^- concentrations on Zn electrodeposition from ammoniacal electrolytes

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International Journal of Minerals,Metallurgy and Materials 2015年第7期22卷 682-687页

作者： Zhi-mei Xia sheng-hai Yang Liang-hong Duan Mo-tang tang School of Metallurgy and Environment Central South University School of Metallurgical Engineering Hunan University of Technology

The effects of Br- and I- concentrations on the cell voltage, anodic polarization, current efficiency （CE）, and energy consumption （EC） of zinc electrodeposition from ammoniacal ammonium chloride solutions were investigated. The surface morphology of zinc deposits was also examined. Scanning electron microscopy （SEM） and X-ray diffraction （XRD） were used to characterize the morphology of zinc deposits and the phase of anodic sediments produced during electrolysis. The results clearly showed that the CE slightly increased from approximately 95.12% in the absence of F and Br- to 97.08% in the presence of 10 g·L-1 Br; in contrast, the CE significantly decreased to less than 83% in the presence of 10 g·L-1 I- . The addition of Br and I- positively affected the EC, which decreased from 2514 kW·h·t-1 to approximately 2300 kW·h·t-1. The results of anodic polarization measurements showed that the voltage drops were 130 and 510 mV when the concentrations of Br- and I- were 10 g·L-1 at a eUlTent density of 400 A·m2, respectively. SEM images showed that the addition of Br- and I- caused different crystal growth mechanisms, which resulted in the production of compact and smooth zinc deposits. The anodic reactions of I were also studied.

关键词： zinc electrodeposition bromide iodide ammonium chloride current efficiency energy consumption

Monotropein Induced Apoptosis and Suppressed Cell Cycle Progression in Colorectal Cancer Cells

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Chinese Journal of Integrative Medicine 2024年第1期30卷 25-33页

作者： GAO Quan LI Lin ZHANG Qi-man sheng Qin-song ZHANG Ji-liang JIN Li-jun SHANG Rui-yan School of Pharmacy and Department of Medical Oncology the Affiliated Hospital of Hangzhou Normal UniversityHangzhou Normal UniversityHangzhou(311121)China Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines Engineering Laboratory of Development and Application of Traditional Chinese MedicinesCollaborative Innovation Center of Traditional Chinese Medicines of Zhejiang ProvinceHangzhou Normal UniversityHangzhou(311121)China Department of Colorectal Surgery the First Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhouChina Beijing Tong Ren tang Chinese Medicine Co. Ltd.Beijing(100000)China Department of Traditional Chinese Medicine Hangzhou Shangcheng District People's HospitalHangzhou(310006)China Department of Gynecology Hangzhou Women's HospitalHangzhou(310008)China

Objective: To determine whether monotropein has an anticancer effect and explore its potential mechanisms against colorectal cancer(CRC) through network pharmacology and molecular docking combined with experimental verification. Methods: Network pharmacology and molecular docking were used to predict potential targets of monotropein against CRC. Cell counting kit assay, plate monoclonal assay and microscopic observation were used to investigate the antiproliferative effects of monotropein on CRC cells HCT116, HT29 and LoVo. Flow cytometry and scratch assay were used to analyze apoptosis and cell cycle, as well as cell migration, respectively in HCT116, HT29, and LoVo cells. Western blotting was used to detect the expression of proteins related to apoptosis, cell cycle, and cell migration, and the expression of proteins key to the Akt pathway. Results: The Gene Ontology and Reactome enrichment analyses indicated that the anticancer potential of monotropein against CRC might be involved in multiple cancer-related signaling pathways. Among these pathways, RAC-beta serine/threonine-protein kinase(Akt1, Akt2), cyclin-dependent kinase 6(CDK6), matrix metalloproteinase-9(MMP9), epidermal growth factor receptor(EGFR), cell division control protein 42 homolog(CDC42) were shown as the potential anticancer targets of monotropein against CRC. Molecular docking suggested that monotropein may interact with the 6 targets(Akt1, Akt2, CDK6, MMP9, EGFR, CDC42). Subsequently, cell activity of HCT116, HT29 and LoVo cell lines were significantly suppressed by monotropein(P<0.05). Furthermore, our research revealed that monotropein induced cell apoptosis by inhibiting Bcl-2 and increasing Bax, induced G_1–S cycle arrest in colorectal cancer by decreasing the expressions of CyclinD1, CDK4 and CDK6, inhibited cell migration by suppressing the expressions of CDC42 and MMP9(P<0.05), and might play an anticancer role through Akt signaling pathway. Conclusions: Monotropein exerts its antitumor

关键词： monotropein Chinese medicine anticancer activity colorectal cancer cells network pharmacology

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混合均匀度对粗粒土强度特性影响的试验研究

中南大学学报（自然科学版） 2024年第6期55卷 2175-2186页

作者：黄超唐明扬张升童晨曦郭鹏赵伟中南大学土木工程学院湖南长沙410075 中铁二局第六工程有限公司四川成都610061

现有研究普遍将粗粒土视为均匀的二元混合料,忽略了粗细颗粒混合均匀程度对其强度特性的影响。为此,首先,提出了一种描述粗粒土混合均匀程度的定量指标Me;其次,通过静三轴试验探讨了应力-应变曲线、弹性模量、破坏强度及抗剪强度指标与... 详细信息

现有研究普遍将粗粒土视为均匀的二元混合料,忽略了粗细颗粒混合均匀程度对其强度特性的影响。为此,首先,提出了一种描述粗粒土混合均匀程度的定量指标Me;其次,通过静三轴试验探讨了应力-应变曲线、弹性模量、破坏强度及抗剪强度指标与混合均匀度Me的内在关系;最后,基于静三轴试验结果,建立了一种综合考虑围压和Me影响的修正邓肯-张模型,并对其适用性及合理性进行鲁棒性验证。研究结果表明:应力-应变曲线随着围压增大而逐渐由应变软化型向应变硬化型曲线过渡;随着Me减小,应力-应变曲线由应变硬化型逐渐发展为应变软化型曲线;当围压与Me增大时,弹性模量与破坏强度均随之增大,且弹性模量在Me从0.25降低至0的过程中衰减幅度可达总衰减幅度的41.3%,破坏强度在Me从1降低至0的过程中衰减幅度可达总衰减幅度的40%以上;随着Me逐渐下降,试样的整体骨架-密实结构在不同区域分别向局部骨架-空隙结构、局部悬浮-密实结构转变,进而致使黏聚力、内摩擦角均随Me下降而逐渐衰减。

关键词：道路工程粗粒土混合均匀度强度特性邓肯-张模型

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新型光纤生物传感器的构建及在食品污染物检测中的应用

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化学进展 2024年第1期36卷 120-131页

作者：黄家麟秦垚华唐盛孔德昭刘畅江苏科技大学环境与化学工程学院镇江212003 江苏科技大学粮食学院镇江212003

食品安全与人们的生活质量息息相关,简便、灵敏及智能化的食品污染物检测方法是食品安全和健康管理的重要保障。传统的分析方法存在检测过程耗时长、成本较高、操作复杂等局限性。基于光与流体相互作用所构建的光纤生物传感器具有信号... 详细信息

食品安全与人们的生活质量息息相关,简便、灵敏及智能化的食品污染物检测方法是食品安全和健康管理的重要保障。传统的分析方法存在检测过程耗时长、成本较高、操作复杂等局限性。基于光与流体相互作用所构建的光纤生物传感器具有信号灵敏、检测快速、实时响应等特点,是近年来兴起的具有多样化功能和高灵敏性的先进光学传感方法,能够实现对食品中各类污染物地快速、精准检测。本文总结了各类新型光纤生物传感器的基本原理、分类及研究现状,综述了其在食品中真菌毒素、重金属离子、抗生素、农药残留物等各类污染物检测方面的应用进展,并展望了这种新型生物传感策略的发展趋势。

关键词：光纤生物传感器食品污染物高灵敏检测

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电力系统两阶段紧急切负荷控制智能预决策

中国电机工程学报 2024年第4期44卷 1260-1271,I0002页

作者：胡泽曾令康姚伟石重托李晟汤涌文劲宇强电磁技术全国重点实验室(华中科技大学) 湖北省武汉市430074 中国电力科学研究院有限公司北京市海淀区100192

电力系统仿真分析是安全稳定控制领域重要技术,可以用于制定与校验紧急控制措施。传统的人工分析仿真数据以决策紧急控制措施的工作模式严重依赖专家经验,在应用于复杂大电网时显得耗时耗力。该文提出一种两阶段紧急切负荷控制智能预决... 详细信息

电力系统仿真分析是安全稳定控制领域重要技术,可以用于制定与校验紧急控制措施。传统的人工分析仿真数据以决策紧急控制措施的工作模式严重依赖专家经验,在应用于复杂大电网时显得耗时耗力。该文提出一种两阶段紧急切负荷控制智能预决策方法,第一阶段决策切负荷点,第二阶段决策切负荷量。首先基于仿真数据,区分3种电压失稳模式:纯电压失稳、耦合电压失稳和混合电压失稳,分别采用不同的负荷筛选方法;然后基于轻量级梯度提升机算法,根据仿真数据直接预估系统恢复稳定所需的切负荷总量,按负荷排序进行分配。结合暂稳仿真校验控制措施的有效性,调整决策量。以我国东北电网为例进行仿真研究,验证了在大电网紧急控制措施制定时,所提两阶段智能决策方法相比完全迭代试凑方法在有效性、快速性和准确性方面的优势。

关键词：电网仿真分析暂态电压失稳紧急控制切负荷轻量级梯度提升机

增施菌剂对玉米产量、土壤养分、光合特性及病虫害的影响

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江西农业学报 2024年第4期36卷 72-76,99页

作者：汤培升甘肃省张掖市甘州区农业技术推广中心甘肃张掖734000

选取4块玉米标准样地,设置了不施肥(CK)、常规施肥(Z_(1))、化肥+西多里微生物菌剂(Z_(2))、化肥+聚谷氨酸复合微生物菌剂(Z_(3))等4个处理,分析了不同菌剂对玉米产量、土壤养分、光合特性及病虫害防治的影响。结果表明:在玉米产量方面... 详细信息

选取4块玉米标准样地,设置了不施肥(CK)、常规施肥(Z_(1))、化肥+西多里微生物菌剂(Z_(2))、化肥+聚谷氨酸复合微生物菌剂(Z_(3))等4个处理,分析了不同菌剂对玉米产量、土壤养分、光合特性及病虫害防治的影响。结果表明:在玉米产量方面,增施菌剂处理后的行粒数、千粒重和产量均高于CK,其中以Z_(3)处理最佳;在土壤养分方面,Z_(1)~Z_(3)处理在拔节期、乳熟期、成熟期的有机质含量均高于CK,以Z_(3)处理为最高;增施菌剂处理后的土壤碱解氮含量均显著高于CK,具体表现为Z_(3)>Z_(2)>Z_(1)>CK;Z_(3)、Z_(2)、Z_(1)处理的土壤速效磷含量在拔节期、乳熟期和成熟期分别是CK的1.78、1.42、1.15倍,1.76、1.48、1.19倍和2.46、1.95、1.47倍;Z_(3)处理的土壤速效钾含量在拔节期、乳熟期和成熟期分别是Z_(2)、Z_(1)处理及CK的1.30、1.17、1.07,1.28、1.19、1.07倍和1.39、1.19、1.09倍;净光合速率和蒸腾速率在乳熟期达到峰值,其中Z_(3)处理的净化光合速率显著高于其他处理,其蒸腾速率分别是Z_(2)、Z_(1)处理及CK的1.51、1.34、1.24倍;在病虫害防治方面,Z_(1)~Z_(3)处理的病株率显著低于CK。综上,增施菌剂可提高玉米产量,改善土壤养分,增强光合特性,减少病虫害,其中化肥+聚谷氨酸复合微生物菌剂的优势最为明显,可在玉米种植中推广应用。

关键词：菌剂玉米产量土壤养分光合特性病虫害防治