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China's Refractories 2019年第4期28卷 12-16页

作者： MA Beiyue WU Hua GAO Zhi REN Xinming zhang yaran School of Metallurgy Northeastern University

SiC powder was rapidly synthesized in an induction furnace with crystalline silicon cutting waste and active carbon as raw materials,and then SiC porous ceramics were prepared at 1600 t for 4 h with carbon embedded using the powder as raw material,the starch and the graphite as pore-forming *** of additions of different pore-forming agents on the phase composition,microstructures,physical properties,and cold crushing strength of the porous ceramics were *** results show that the main crystalline phases of the synthetic powder areα-S iC(6H-SiC)andβ-SiC(3C-SiC).The phase composition of the porous ceramics includesα-S iC(6H-SiC),β-SiC(3C-SiC),FeSi,quartz and *** apparent porosity and closed porosity of the porous ceramics prepared by adding starch are higher,and the cold compressive strength of the porous ceramics added with graphite is *** increasing the additions of the starch,the apparent porosity,closed porosity and linear shrinkage ratio of the porous ceramics increase,and the bulk density decreases *** 20 mass%starch is added,the apparent porosity,closed porosity,linear shrinkage ratio and cold compressive strength are 57.05%,2.03%,5.10%and 10.20 MPa,respectively.

关键词： silicon carbide porous ceramics pore-forming agent crystalline silicon cutting waste

DNA methylation and alternative splicing modulate FBXW11 gene expression in Holstein bull testis and are correlated with sperm quality

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BIOCELL 2021年第1期45卷 79-87页

作者： YONG LIU ZHIHUA JU QIANG JIANG WENHAO LIU CHUNHONG YANG yaran zhang XIUGE WANG YAPING GAO XIAOCHAO WEI YAN SUN JINPENG WANG MINGHAI HOU LING YANG JINMING HUANG Dairy Cattle Research Center Shandong Academy of Agricultural SciencesJinan250100China College of Life Sciences and Food Engineering Hebei University of EngineeringHandan056021China

F-box and WD-40 domain protein 11(FBXW11)is an important component of the E3 ubiquitin-ligase enzyme that plays a key role in the ubiquitin-dependent regulation of *** our previous research,the mRNA expression of FBXW11 in bull sperm with high motility is significantly higher than that with low *** the present study,the protein expression levels of FBXW11 in bull testicular tissues with low-performance sperm quality groups were significantly higher than those in normal performance *** immunohistochemistry result demonstrated that FBXW11 protein was located in the periphery of Leydig cells and seminiferous *** splice variants of the FBXW11 gene,namely,FBXW11-tv1,FBXW11-tv2,and FBXW11-tv3,were identified in testicular *** splicing patterns of the three variants are exon *** transcript FBXW11-tv2 expressions were the highest in each *** low-performance groups displayed higher FBXW11-tv1 and FBXW11-tv2 transcript expressions than the normal performance *** CpG islands were located within the 5’UTR and exon 1-2 region of the FBXW11 *** sequencing PCR results demonstrated that the methylation levels of 11 methylation sites in the CpG island 2 from−99 to−43 in the normal performance groups were significantly lower than those in the low-performance *** correlation analysis suggested that the CpG island 2 methylation level was negatively correlated with sperm motility and the transcript FBXW11-tv2 expression *** data revealed that alternative splicing and DNA methylation jointly regulated FBXW11 gene expression and were correlated with sperm quality traits during spermatogenesis in Holsteins.

关键词： FBXW11 Alternative splicing DNA methylation Bull Sperm quality traits

Effect of Main Material Ratio on Properties of SiC-Al_2O_3 Porous Ceramics via Polymeric Replication Method

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China's Refractories 2018年第3期27卷 44-47页

作者： REN Xinming MA Beiyue SU Chang YU Jingyu zhang yaran School of Metallurgy Northeastern University

In order to fabricate porous ceramics with good properties and proper production cost,SiC-Al2 O3 porous ceramics were prepared at 1 450 ℃ for 2 h from the powders of commercial silicon carbide and white fused corundum via a polymeric replication method. Effects of the mass ratio of SiC powder to white fused corundum powder（ 1 ∶ 3,1 ∶ 1 and 3 ∶ 1） on the appearance,phase composition,sintering properties and thermal shock resistance were investigated. The research results indicate that the as-prepared Si C-Al2 O3 porous ceramics have uniform pores,and their linear shrinkage ratio,apparent porosity and bulk density reach 4. 70%,67. 17%and 0. 83 g·cm-3,respectively. The thermal shock cycles from 1 400 ℃ to room temperature reach 23 including 15 cycles in air cooling condition and then 8 cycles in water cooling condition. Their main phases areα-Al2 O3 and Al6 Si2 O13 as well as a small amount of SiC and free SiO2. The as-prepared porous ceramic with the ratio of m（ SiC） ∶ m（ Al2 O3） = 1∶ 1 possesses prior comprehensive properties.

关键词： porous ceramics polymeric replication method silicon carbide white fused corundum sintering properties thermal shock resistance

Biocompatibility of Porous Spherical Calcium Carbonate Microparticles on Hela Cells

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World Journal of Nano Science and Engineering 2012年第1期2卷 25-31页

作者： yaran zhang Ping Ma Yao Wang Juan Du Qi Zhou Zhihong Zhu Xu Yang Junlin Yuan Basic Medical College Xianning University Xianning China Laboratory of Environmental Sciences College of Life Sciences Central China Normal University Wuhan China Nanotechnology Institute College of Physical Science and Technology Central China Normal University Wuhan China School of Life Sciences Fudan University Shanghai China

Recently there has been a wide concern on inorganic nanoparticles as drug delivery carriers. CaCO3 particles have shown promising potential for the development of carriers for drugs, but little research had been performed regarding their safe dosage for maximizing the therapeutic activity without harming biosystems. In this study, we assessed the biological safety of porous spherical CaCO3 microparticles on Hela cells. The reactive oxygen species (ROS), glutathione (GSH), carbonyl content in proteins (CCP), DNA-protein crosslinks (DPC) and cell viability were measured. Results showed that with the exposure concentration increase, ROS and CCP in Hela cells presented a significant increase but GSH contents in Hela cells and cell viability showed a significant decrease respectively compared with the control. DPC coefficient ascended, but no statistically significant changes were observed. The results indicated that porous spherical CaCO3 microparticles may induce oxidative damage to Hela cells. But compared with other nanomaterials, porous spherical CaCO3 appeared to have good biocompatibility. The results implied that porous spherical calcium carbonate microparticles could be applied as relatively safe drug vehicles, but with the caveat that the effect of high dosages should not be ignored when attempting to maximize therapeutic activity by increasing the concentration.

关键词： Calcium Carbonate Microparticles Hela Cells Biological Safety

Preparation of SiC Porous Ceramics by Crystalline Silicon Cutting Waste

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China's Refractories 2018年第4期27卷 46-50页

作者： zhang yaran MA Beiyue YU Jingyu SU Chang REN Xinming QIAN Fan LIU Guoqi LI Hongxia YU Jingkun School of Metallurgy Northeastern University State Key Laboratory of Advanced Refractories Sinosteel Luoyang Institute of Refractories Research Co.Ltd.

SiC porous ceramics were prepared at 1 400 ℃ for4 h with crystalline silicon cutting waste and activated carbon as main starting materials and NH4HCO3 as the pore-forming agent. Effects of NH4HCO3 additions( 0,20%,30%,40%,by mass) on the phase composition,microstructure,sintering properties,cold compressive strength and thermal shock resistance of as-prepared Si C porous ceramics were investigated. The results show that:( 1) addition of NH4HCO3 remarkably influences the apparent porosity and cold compressive strength of specimens. The apparent porosity achieves its maximum value( 63. 40%) when 40% NH4HCO3 is added,while the minimum cold compressive strength is 4. 77 MPa;( 2) the specimen with 40% NH4HCO3 has the best thermal shock resistance. The thermal cycling times between1 000 ℃ to room temperature reach 62;( 3) the addition of NH4HCO3 does not remarkably affect the phase composition of the specimens;( 4) the specimens include a large number of SiC particles and a small amount of SiC whiskers.

关键词： crystalline silicon cutting waste silicon carbide porous ceramics pore-forming agent sintering properties cold compressive strength thermal shock resistance

“忽冷忽热”的杏仁核:与攻击相关的重要核团

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心理科学进展 2023年第7期31卷 1206-1227页

作者：赵辉张亚冉肖玉琴张卓杨波中国政法大学社会学院北京102249

攻击是有意对他人造成直接伤害的行为,可以分为反应性攻击和主动性攻击。攻击行为的发生有其神经生理基础,作为情绪加工和学习的关键脑区,杏仁核与攻击有着密切的关联。战斗-逃跑机制模型、暴力抑制机制模型和恐惧功能障碍假说强调了杏... 详细信息

攻击是有意对他人造成直接伤害的行为,可以分为反应性攻击和主动性攻击。攻击行为的发生有其神经生理基础,作为情绪加工和学习的关键脑区,杏仁核与攻击有着密切的关联。战斗-逃跑机制模型、暴力抑制机制模型和恐惧功能障碍假说强调了杏仁核对于攻击的重要性。表现出攻击或暴力行为的群体存在杏仁核的结构缺陷和功能障碍,其中功能障碍有两种相反的异常表现:在具有反应性攻击表现的高危人群中,杏仁核对威胁性刺激的反应增强(“热”反应);而以主动性攻击为主的人群如带有冷酷无情特质的精神病态人群,会表现出对威胁性刺激以及他人痛苦情绪线索的杏仁核反应减弱,以及在恐惧条件学习和道德决策的过程中杏仁核的激活不足的现象(“冷”反应)。这些功能障碍损害了个体在威胁反应、共情能力、惩罚回避以及道德决策等方面的正常水平。未来研究需人群研究和过程研究并举,关注杏仁核子结构的功能,探究攻击的神经网络基础,并探索有效的暴力防治干预手段。

关键词：杏仁核反应性攻击主动性攻击精神病态

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气候变化情景下流域水环境承载力评估方法研究

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北京大学学报（自然科学版） 2023年第2期59卷 242-250页

作者：张扬付正辉张雅然郭怀成姜霞王书航中国环境科学研究院北京100012 北京大学环境科学与工程学院北京100871 中交(天津)生态环保设计研究院有限公司天津300461

以青海省湟水流域为研究案例,考虑气候变化与流域水文循环的密切联系以及气候变化对水环境系统的剧烈影响,构建气候变化影响下的流域水环境承载力评估方法体系。该体系从系统性和整体性的角度进行时间与空间尺度上的匹配,从而精确地评... 详细信息

以青海省湟水流域为研究案例,考虑气候变化与流域水文循环的密切联系以及气候变化对水环境系统的剧烈影响,构建气候变化影响下的流域水环境承载力评估方法体系。该体系从系统性和整体性的角度进行时间与空间尺度上的匹配,从而精确地评估气候变化对流域尺度水文循环的影响,开展水环境承载力计算,最终建立气候变化影响下的流域水环境承载力动态变化评估。研究结果表明,气候变暖将导致湟水流域水环境承载力下降,但随着时间推移,未来气候变化情景下的水环境承载力总体上呈现改善的趋势。

关键词：水环境气候变化水资源水环境承载力

MCM-41负载手性Salen-Mn(Ⅲ)配合物的制备及其对不对称环氧化的催化性能

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催化学报 2007年第1期28卷 85-90页

作者：赵继全张雅然张月成河北工业大学化工学院天津300130

三乙氧基硅丙胺与介孔分子筛MCM-41表面的羟基在甲苯中回流反应得到氨丙基官能团化的MCM-41,再利用氨基与Salen-Mn(Ⅲ)上的活性酯基生成酰胺键,将手性Salen-Mn(Ⅲ)配合物负载到MCM-41上,实现了手性均相催化剂的多相化.分别利用FT-IR,DRU... 详细信息

三乙氧基硅丙胺与介孔分子筛MCM-41表面的羟基在甲苯中回流反应得到氨丙基官能团化的MCM-41,再利用氨基与Salen-Mn(Ⅲ)上的活性酯基生成酰胺键,将手性Salen-Mn(Ⅲ)配合物负载到MCM-41上,实现了手性均相催化剂的多相化.分别利用FT-IR,DRUV-Vis,XRD,ICP和N2吸附等手段对负载型催化剂进行了表征.结果表明,手性Salen-Mn(Ⅲ)配合物成功负载到MCM-41上,但MCM-41和手性Salen-Mn(Ⅲ)配合物固有的结构保持不变.以次氯酸钠和间氯过氧苯甲酸为氧化剂,考察了负载型催化剂对1,2-二氢萘不对称环氧化反应的催化性能,结果表明,负载型催化剂的催化活性比相应均相催化剂的低,但对映体选择性有所提高.在NaClO/PyNO氧化剂体系中20℃反应12h,1,2-二氢萘环氧化物的收率达45.9%,对映体过量值为84.3%.负载型催化剂在循环使用5次后Mn的流失达34%.

关键词： MCM-41分子筛手性Salen锰(Ⅲ)配合物负载型催化剂不对称环氧化二氢萘

基于雾霾天气探索我国环境监测的社会化及能力建设

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环境与发展 2018年第1期30卷 166-166,168页

作者：张亚冉山东省滨州市环境保护监测站山东滨州256600

最近几年,雾霾现象一直困扰着我国对大多数的城市地区,这种恶劣天气的出现给人们的生存处境以及正常生产生活带来了严峻的挑战。与此同时,也能够从种种雾霾天气的产生得出我国的环境监测管理体制存在有很大的漏洞。所以说,要想从根源上... 详细信息

最近几年,雾霾现象一直困扰着我国对大多数的城市地区,这种恶劣天气的出现给人们的生存处境以及正常生产生活带来了严峻的挑战。与此同时,也能够从种种雾霾天气的产生得出我国的环境监测管理体制存在有很大的漏洞。所以说,要想从根源上杜绝此类状况的再次出现,就需要将目光聚焦在国家的社会化及生态能力构建的层面上来,探究出适合我国发展形势的生态治理途径。

关键词：雾霾天气环境监管体制社会化形式生态能力构建

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钢筋混凝土梁受弯抗震性能尺寸效应试验研究

应用基础与工程科学学报 2018年第2期26卷 346-356页

作者：周宏宇杨聪昆杜修力李振宝张雅然北京工业大学建筑工程学院

对不同尺寸钢筋混凝土悬臂梁构件开展低周往复荷载试验,以研究尺寸效应对受弯构件抗震性能的影响.试验分5个尺度,共计10个试件,悬臂梁试件剪跨比为4,截面梁高范围0.2～1.0m,能够反映受弯构件抗震性能在尺寸上的差异.试验结果表明：往复... 详细信息

对不同尺寸钢筋混凝土悬臂梁构件开展低周往复荷载试验,以研究尺寸效应对受弯构件抗震性能的影响.试验分5个尺度,共计10个试件,悬臂梁试件剪跨比为4,截面梁高范围0.2～1.0m,能够反映受弯构件抗震性能在尺寸上的差异.试验结果表明：往复荷载作用下,受弯构件滞回环饱满,抗震性能较好.试件抗震性能在尺寸上的差别主要体现在试验加载后期,大尺寸构件在超越极限承载状态后,虽然根部受压区混凝土压碎,但依然保持较高的阻尼系数和耗能能力.构件在超越屈服承载状态后,其承载和延性储备随构件尺寸增大整体呈增长趋势.混凝土材料的变形能力在大尺寸构件中变差.

关键词：钢筋混凝土梁弯曲变形抗震性能尺寸效应