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全尾砂物理化学性质及其似膏体充填试验

世界有色金属 2024年第12期 183-185页

作者：朱久隆李帅杭康张锋德王新民项振忠白银有色集团股份有限公司小铁山矿甘肃白银730900 中南大学资源与安全工程学院湖南长沙410083

小铁山选矿厂产出的全尾砂粒径级配较细,-400目以下颗粒占比达到45%左右,通过对全尾砂物理化学性能进行测定,并提出用全尾砂与粉煤灰组合料浆似膏体充填工艺替代现有分级尾砂充填工艺,可以简化选厂供砂工艺、改善充填料浆颗粒级配、减... 详细信息

小铁山选矿厂产出的全尾砂粒径级配较细,-400目以下颗粒占比达到45%左右,通过对全尾砂物理化学性能进行测定,并提出用全尾砂与粉煤灰组合料浆似膏体充填工艺替代现有分级尾砂充填工艺,可以简化选厂供砂工艺、改善充填料浆颗粒级配、减少水泥流失,并有效解决小铁山矿分级尾砂颗粒级配差的问题。

关键词：粒径级配似膏体充填分级尾砂

益生菌添加水平与犊牦牛瘤胃发酵参数的量效关系研究

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饲料研究 2024年第15期47卷 6-12页

作者：袁越罗晓林官久强安添午赵洪文任子利赵彦玲张翔飞西藏农牧学院动物科学学院西藏林芝860000 四川省草原科学研究院四川成都611731

研究旨在探索不同水平复合益生菌与犊牦牛瘤胃发酵参数的量效关系,并确定适宜添加水平。选取4头健康的3月龄犊牦牛,通过口腔取样装置采集瘤胃液,采用人工瘤胃装置,以犊牛代乳粉为发酵底物进行体外发酵,复合益生菌(乳酸杆菌、芽孢杆菌、... 详细信息

研究旨在探索不同水平复合益生菌与犊牦牛瘤胃发酵参数的量效关系,并确定适宜添加水平。选取4头健康的3月龄犊牦牛,通过口腔取样装置采集瘤胃液,采用人工瘤胃装置,以犊牛代乳粉为发酵底物进行体外发酵,复合益生菌(乳酸杆菌、芽孢杆菌、酵母菌复合益生菌≥9.98×1011 CFU)添加水平分别为0(对照组)、0.025%(0.025%组)、0.050%(0.050%组)、0.100%(0.100%组)、0.200%(0.200%组)、0.400%(0.400%组)。设置发酵第3、6、9、12、24、48 h共6个采样时间点,测定各处理组各时间点发酵参数:pH值、产气量(GP)、氨态氮(NH3-N)、微生物蛋白(MCP)、乙酸(AA)、丙酸(PA)、丁酸(BA)和总挥发性脂肪酸(TVFA)的数值,基于发酵参数计算多项指标综合指数(MFAEI)。结果显示:添加复合益生菌有降低瘤胃发酵pH值的趋势。0.100%组和0.200%组发酵3~24 h的GP显著高于对照组(P0.200%组>0.400%组>0.050%组>0.025%组。研究表明,添加复合益生菌能够有效降低NH3-N浓度,提升发酵GP及MCP、TVFA浓度,促进犊牦牛瘤胃微生物发酵功能建立,添加水平为0.100%时效果最佳。

关键词：复合益生菌犊牦牛体外发酵发酵参数

基于数字图像的非均匀岩土材料渗透系数研究（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2017年第2期18卷 124-137页

作者： Long YAN Qing-xiang MENG Wei-ya XU Huan-ling wang Qiang ZHANG jiu-chang ZHANG Ru-bin wang Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai University Nanjing 210098 China Department of Civil & Environmental Engineering University of Waterloo Waterloo N2L 3G1 Canada Key Laboratory of Coastal Disaster and Defense of Ministry of Education Hohai University Nanjing 210098 China Department of Civil Engineering University of Toronto Toronto M5S 1A4 Canada

目的:建立一种较为快速和快速确定非均匀岩土材料渗透系数的方法。创新点:建立了一种可以从图像到数值模型的数字图像方法:通过拍照、CT等手段获取岩土材料的图像,进而通过数值分析确定等效参数。方法:1.将采集到彩色图像从RGB空间转化... 详细信息

目的:建立一种较为快速和快速确定非均匀岩土材料渗透系数的方法。创新点:建立了一种可以从图像到数值模型的数字图像方法:通过拍照、CT等手段获取岩土材料的图像,进而通过数值分析确定等效参数。方法:1.将采集到彩色图像从RGB空间转化到HSI空间,选取识别度较高的空间进行二值化处理;2.获取二值化图像后采用邻域标记算法标记,结合本文提出的算法提取边界(图9和10);3.结合边界修正算法对锯齿状边界进行修正(图11);4.确定表征细观几何模型(图12和表1);5.绘制网格开展数值分析,确定宏观参数。结论:1.基于数值图像的非均匀岩土材料渗透系数确定方法可以较为准确地估算渗透系数,可以为工程设计提供初步依据。2.非均匀岩土材料具有明显的尺寸效应,随着尺寸增加,渗透率的变化逐渐趋于稳定;当材料视为岩石和土体的二元介质时,两种性质差异在10倍以内对宏观特性的影响较大,大于10倍之后影响减弱。3.岩土材料渗透率随着内部块石含量的增加而减小,但是内部块石的形态对渗透率也有一定的影响。

关键词：非均质岩土材料数字图像宏观渗透系数尺寸效应

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硼肥和保水剂配施对甜菜硼吸收利用的影响

山东农业大学学报（自然科学版） 2024年第5期55卷 687-693页

作者：陈雪珂黄睿敏罗静静魏正美陈浩李想张彦朋董心久樊华石河子大学农学院新疆石河子832003 新疆生产建设兵团第九师农业科学研究所(畜牧科学研究所) 新疆塔城834600 新疆农业科学院经济作物研究所新疆乌鲁木齐830091

以甜菜品种‘Beta 796’和‘ST 13092’为试验材料,采用裂区设计,以施硼量为主区[包括施硼量0 kg·hm^(-2)(M0)、1.2 kg·hm^(-2)(M1)、2.4 kg·hm^(-2)(M2)、4.8 kg·hm^(-2)(M3)],保水剂为副区[包括保水剂施用量0 kg·hm^(-2)(Z0)、75 kg·hm^(-2)(Z1)],研究硼肥和保水剂配施对滴灌甜菜硼养分吸收和产量的影响。结果表明:甜菜硼含量随施硼量的增加呈现先增加后降低的趋势,在M2处理达到最大。甜菜不同器官硼含量表现为叶片>叶柄>块根,其中M2处理条件下甜菜叶片、叶柄和块根硼含量较其他处理分别提高6.09%~54.55%、7.17%~49.68%和11.08%~73.70%。与叶丛期相比,收获期甜菜叶片和叶柄硼积累量占比分别降低8%~19%和3%~7%,块根硼积累量占比提高14%~24%。施用保水剂后,甜菜叶片、叶柄和块根硼含量较不施用保水剂处理分别提高10.56%~32.73%、3.66%~25.04%和20.11%~57.38%。相同处理条件下,‘Beta 796’叶片、叶柄和块根硼积累量比‘ST 13092’提高0.45%~15.64%、0.89%~13.72%和1.15%~15.79%。‘Beta 796’和‘ST 13092’品种的硼肥表观利用率分别为42.43%和37.89%。因此,将3.1~3.5 kg·hm^(-2)硼肥和75 kg·hm^(-2)保水剂在叶丛期随水滴施能够实现甜菜增产增效,为新疆甜菜可持续生产管理提供了案例支撑。

关键词：甜菜硼肥保水剂硼吸收利用

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Sphingosine 1-phosphate receptor 1 regulates bloodbrain barrier permeability in epileptic mice

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Neural Regeneration Research 2023年第8期18卷 1763-1769页

作者： Li-xiang Yang Yuan-Yuan Yao jiu-Rong Yang Hui-Lin Cheng Xin-Jian Zhu Zhi-Jun Zhang Department of Neurosurgery Zhongda HospitalSchool of MedicineSoutheast UniversityNanjingJiangsu ProvinceChina Department of Pharmacology Medical School of Southeast UniversityNanjingJiangsu ProvinceChina Department of Neurology Zhongda HospitalSchool of MedicineInstitution of NeuropsychiatryKey Laboratory of Developmental Genes and Human DiseaseSoutheast UniversityNanjingJiangsu ProvinceChina Department of Mental Health and Public Health Faculty of Life and Health SciencesShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina

Destruction of the blood-brain barrier is a critical component of epilepsy *** studies have demonstrated that sphingosine 1-phosphate receptor 1 contributes to the modulation of vascular ***,its effect on blood-brain barrier permeability in epileptic mice remains *** this study,we prepared pilocarpine-induced status epilepticus models and pentylenetetrazol-induced epilepsy models in C57BL/6 mice.S1P1 expression was increased in the hippocampus after status epilepticus,whereas tight junction protein expression was decreased in epileptic mice compared with *** injection of SEW2871,a specific agonist of sphingosine-1-phosphate receptor 1,decreased the level of tight junction protein in the hippocampus of epileptic mice,increased blood-brain barrier leakage,and aggravated the severity of seizures compared with the control.W146,a specific antagonist of sphingosine-1-phosphate receptor 1,increased the level of tight junction protein,attenuated blood-brain barrier disruption,and reduced seizure severity compared with the ***,sphingosine 1-phosphate receptor 1 promoted the generation of interleukin-1βand tumor necrosis factor-αand caused *** of tight junction protein and blood-brain barrier integrity by sphingosine 1-phosphate receptor 1 was reversed by minocycline,a neuroinflammation *** tests revealed that sphingosine 1-phosphate receptor 1 exacerbated epilepsy-associated depression-like ***,specific knockdown of astrocytic S1P1 inhibited neuroinflammatory responses and attenuated blood-brain barrier leakage,seizure severity,and epilepsy-associated depression-like *** together,our results suggest that astrocytic sphingosine 1-phosphate receptor 1 exacerbates blood-brain barrier disruption in the epileptic brain by promoting neuroinflammation.

关键词： adeno-associated virus astrocytes blood-brain barrier epilepsy epilepsy-associated depression-like behavior neuroinflammation pentylenetetrazol pilocarpine tight junction

Recent research and development of thick CVD tungsten coatings for fusion application

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Tungsten 2020年第1期2卷 83-93页

作者： Zhe Chen You‑Yun Lian xiang Liu Fan Feng Bin‑You Yan Jian‑Bao wang Yan‑Wei Lv jiu‑Peng Song Chun‑Jia Liu Lai‑Zhong Cai Southwestern Institute of Physics Chengdu 610041China China National R&D Center for Tungsten Technology Xiamen Tungsten Co.Ltd.Xiamen 361009China

As the interface closest to the edge plasma of a fusion reactor reacting deuterium(D)and tritium(T),plasma-facing material(PFM)need to withstand extreme service conditions with the high particle flux,high heat load,and neutrons with energy up to 14.1 ***(W)is the primary candidate of PFMs in future fusion reactors due to its high melting point,good thermal conductivity,excellent irradiation resistance,and low hydrogen/helium *** far,powder metallurgy is a leading route for the preparation of W-based *** alternative approach could be the coating technique,which has advantages on fabricating W PFMs and plasma-facing component(PFC)*** the past several years,inspiring results were achieved in the preparation process and performance evaluation of the W coating with high purity,excellent thermal conductivity,and thickness at the millimeter level by atmospheric pressure chemical vapor deposition(APCVD).No obvious grain growth and hardness decrease were observed when the annealing temperature was lower than 1500°C,indicating its good thermal *** as-deposited coating exhibited a comparable thermal shock resistance with the conventional W *** the polished sample showed a high crack threshold(0.33-0.44 GW·m^(−2))when exposed to edge localized mode like transient at room temperature,compared to the unpolished *** performance of the chemical vapor deposition(CVD)-W exposed to deuterium(D)plasma and fission neutron were also ***,the practicality of preparation of large-scale W-based PFM by this technique is also *** paper gives a short overview on the recent research and development status of the thick W coating prepared by APCVD at Xiamen Tungsten Co.,Ltd and Southwestern Institute of Physics for using as PFM and PFC in fusion devices.

关键词： Tungsten coatings Chemical vapor deposition Plasma-facing materials Plasma-facing component

Detection of Distorted Segregation in Genotype of Pollen Calli Derived from Hybrid F_1 of Cultivated Rice (Oryza sativa L.) Using SSR Markers

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Agricultural Sciences in China 2006年第6期5卷 412-416页

作者： YAO Yan LU Yong-gen LIU xiang-dong FENG jiu-huan ZHANG Gui-quan Guangdong Provincial Key Laboratory of Plant Molecular Breeding South China Agricultural University Guangzhou 510642 P.R.China

S-a, S-b and S-c are three loci for F1 pollen sterility in cultivated rice （Oryza sativa L.）. Taichung 65 （T65） is all Sj/Sj at these three loci, while its F1 pollen sterile near-isogenic lines, TISL2 （S-b）, TISL4 （S-a） and TISL5 （S-c） is Sj/Sj according to their respective sterility locus. Using SSR molecular marker to detect the segregation of the allele Si and Sj in pollen calli population induced from different hybrid F1, which have different pollen sterility locus, showed that the segregation of allele Si and Sj was distorted. The distorted direction of pollen calli population in vitro was not the same as F2 population in vivo. The quantities of pollen callus carrying Sj were much more than that of carrying Siat S-a and S-c locus, the ratio of Si and Sj were 1：4.81 and 1：1.96 respectively. But the opposite tendency was observed at S-b locus, the ratio of Si and Sj being 1：0.35. At the same time, all these results were undisturbed by either culture medium or culture period.

关键词： rice (Oryza sativa L.) pollen sterility pollen callus distorted segregation SSR marker

Extremely Narrow Sb Delta-Doped Epitaxial Layer Characterized by X-Ray Reflectivity

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Chinese Physics Letters 1997年第9期14卷 686-689页

作者： JIANG Zui-min XIU Li-song JIANG Xiao-ming ZHENG Wen-li LU Xue-kun ZHU Hai-jun ZHANG xiang-jiu wang Xun Fudan T.D.Lee Physics Laboratory Surface Physics Laboratoryfudan UniversityShanghai 200433 Synchrotron Radiation Laboratory Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100039 Surface Physics Laboratory Fudan UniversityShanghai 200433

An Sb delta doping layer in silicon is grown at the temperature of 300℃ by silicon molecular beam epitaxy and characterized by the small angle x-ray reflectivity measurement using synchrotron radiation *** oscillations of the reflectivity caused by dopant Sb at Q as large as 14.5 are *** of this curve as a whole shows that the total amount of dopant Sb is 0.15 monolayer and is restricted to two atomic *** extremely narrow Sb delta doping structure without Sb segregation is thus obtained at the growth temperature of 300℃ as verified by the experiment.

关键词： dopant reflectivity doping

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混沌信号在无线传感器网络中的盲分离

物理学报 2014年第5期63卷 44-51页

作者：黄锦旺冯久超吕善翔华南理工大学电子与信息学院广州510641

混沌信号在本质上属于非线性非高斯信号,它在无线传感器网络下的应用还涉及到信号量化问题,这使得混沌信号在此应用环境下的信号盲分离更为棘手.针对此问题,本文在容积卡尔曼粒子滤波的框架下提出一种解决方法.文中首先推导出观测信号... 详细信息

混沌信号在本质上属于非线性非高斯信号,它在无线传感器网络下的应用还涉及到信号量化问题,这使得混沌信号在此应用环境下的信号盲分离更为棘手.针对此问题,本文在容积卡尔曼粒子滤波的框架下提出一种解决方法.文中首先推导出观测信号的概率密度函数,在量化比特有限的情况下,采用最优量化器,获得最优的量化结果.在此基础上,使用容积卡尔曼滤波器产生粒子滤波中的重要性概率密度函数,融入最新的观测值,提高粒子对系统状态后验概率的逼近,提高信号盲分离的精度.仿真结果表明算法能够有效地分离混合混沌信号,参数估计的精度及其运算量均优于已有的无先导卡尔曼粒子滤波算法,其运行时间为无先导卡尔曼粒子滤波算法的88.77%.

关键词：混沌信号盲分离无线传感器网络粒子滤波器