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ICP-MS法结合化学计量学分析不同菲牛蛭元素差异

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化学研究与应用 2024年第7期36卷 1625-1631页

作者：王嘉慧柳志诚杨国华杨玉升陶欧马涛刘永刚北京中医药大学中药学院北京102401 云南世纪华宝医药产业开发有限公司云南楚雄675000

采用ICP-MS法结合指纹图谱、相关性分析和主成分分析研究不同批次、不同生长发育时期的菲牛蛭中无机元素的含量特征。26种无机元素在0~1000μg·L^(-1)线性关系良好,R^(2)≥0.9998,检出限0.0009~0.5094μg·L^(-1),精密度RSD≤1.80%、... 详细信息

采用ICP-MS法结合指纹图谱、相关性分析和主成分分析研究不同批次、不同生长发育时期的菲牛蛭中无机元素的含量特征。26种无机元素在0~1000μg·L^(-1)线性关系良好,R^(2)≥0.9998,检出限0.0009~0.5094μg·L^(-1),精密度RSD≤1.80%、重复性RSD≤2.94%;平均加样回收率85.79%(120.27%,RSD≤3.16%。结果显示Zr、Sc、Te、Bi、Mo、In在菲牛蛭中只能微量检出或未检出。Na、Mg、Al、K、Fe、Ga、ba在不同批次间差异较大;K、Ca、Fe、Al、Mn等元素含量具有较强的特征性,可作为鉴定不同月龄菲牛蛭的参考依据。ICP-MS法可用于菲牛蛭中26种无机元素的含量测定,菲牛蛭中的无机元素含量差异可作为其不同生长发育时期的分析依据。

关键词：菲牛蛭无机元素电感耦合等离子体质谱统计分析

Effects of electrochemical oxidation on surface and mechanical properties of dry-jet wet spun carbon fibers

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北京化工大学学报（自然科学版） 2022年第5期49卷 22-29页

作者： ZhaO ZeHua ma yan SHEN ZhiGang CHEN Liang WANG XiaoXu LIU Jie College of materials Science and Engineering Beijing University of Chemical TechnologyBeijing 100029 Institute of Aerospace materials and Technology Beijing 100076 Shanghai Research Institute of Petrochemical Technology Shanghai 201211China

The surface of dry-jet wet spun carbon fibers(CFs)is relatively smooth compared with those of wet spun CFs,which results in weak interfacial interactions between the fiber and the polymer resin.A surface functionalization treatment is particularly important to unleash the full potential of the superior mechanical properties of dry-jet wet spun *** this study,the effects of electrochemical oxidation treatment time and current density on the surface structures and the mechanical properties of dry-jet wet spun CFs were *** interlaminar shear strength of the CFs improves significantly from 69 to 84 MPa after 120 s of *** structural analysis reveals that the improvements are due to the addition of oxygen-containing functional groups and the optimization of the morphology on the surface of the CFs.

关键词： carbon fibers dry-jet wet spun electrochemical oxidation interlaminar shear strength

Establishment of an efficient regeneration and genetic transformation system for malus prunifolia Borkh. ‘Fupingqiuzi’

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Journal of Integrative Agriculture 2022年第9期21卷 2615-2627页

作者： LIU yu-song WANG Hong-ying ZhaO yong-juan JIN yi-bo LI Chao ma Feng-wang State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple College of HorticultureNorthwest A&F UniversityYangling 712100P.R.China

malus prunifolia Borkh. ‘Fupingqiuzi’ has significant ecological and economic value and plays a key role in germplasm development and resistance research. However, its long juvenile phase and high heterozygosity are barriers to the identification of ‘Fupingqiuzi’ progeny with excellent traits. In-vitro regeneration techniques and Agrobacterium-mediated genetic transformation systems can efficiently produce complete plants and thus enable studies of gene ***, optimal regeneration and genetic transformation systems for ‘Fupingqiuzi’ have not yet been ***, we evaluated the factors that affect the in-vitro regeneration and transformation of ‘Fupingqiuzi’. The best results were obtained when transverse leaf sections were used as explants, and they were grown in dark culture for three weeks with their adaxial sides contacting the culture medium(MS basal salts, 30 g Lsucrose, 8 g Lagar, 5 mg L6-benzylaminopurine(6-ba), 2 mg Lthidiazuron(TDZ), and 1 mg L1-naphthlcetic acid(NAA), pH 5.8). A genetic transformation system based on this regeneration system was optimized: after inoculation with A. tumefaciens solution for 8 min, 4 days of co-culture, and 3 days of delayed culture, the cultures were screened with cefotaxime(150 mg L) and kanamycin(15 mg L). We thus established an efficient regeneration and genetic transformation system for ‘Fupingqiuzi’, enabling the rapid production of transgenic material. These findings make a significant contribution to apple biology research.

关键词： malus prunifolia Borkh.‘Fupingqiuzi’ regeneration system Agrobacterium-mediated transformation system

A novel spiking neural network of receptive field encoding with groups of neurons decision

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Frontiers of Information Technology & Electronic Engineering 2018年第1期19卷 139-150页

作者： yong-qiang ma Zi-ru WANG Si-yu yU ba-dong CHEN Nan-ning ZHENG Peng-ju REN Institute of Artificial Intelligence and Robotics Xi'an Jiaotong University

Human information processing depends mainly on billions of neurons which constitute a complex neural network,and the information is transmitted in the form of neural *** this paper,we propose a spiking neural network(SNN),named MD-SNN,with three key features:(1) using receptive field to encode spike trains from images;(2) randomly selecting partial spikes as inputs for each neuron to approach the absolute refractory period of the neuron;(3) using groups of neurons to make *** test MD-SNN on the MNIST data set of handwritten digits,and results demonstrate that:(1) Different sizes of receptive fields influence classification results significantly.(2) Considering the neuronal refractory period in the SNN model,increasing the number of neurons in the learning layer could greatly reduce the training time,effectively reduce the probability of over-fitting,and improve the accuracy by 8.77%.(3) Compared with other SNN methods,MD-SNN achieves a better classification;compared with the convolution neural network,MD-SNN maintains flip and rotation invariance(the accuracy can remain at 90.44% on the test set),and it is more suitable for small sample learning(the accuracy can reach 80.15%for 1000 training samples,which is 7.8 times that of CNN).

关键词：神经网络神经原编码小说信息处理随机选择图象输入

Secondary coronary artery ostial lesions:Three case reports

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World Journal of Clinical Cases 2022年第20期10卷 7045-7053页

作者： Xiao-Ping Liu hai-Jun Wang Jin-Liang Gao Guo-Li ma Xin-yun Xu Li-Na Ji Rui-Xia He ba-ya-Er Qi Li-Cheng Wang Chang-Qing Li ya-Jiang Zhang yu-bao Feng Department of Cardiology Ordos Clinical College of Inner Mongolia Medical UniversityOrdos Central HospitalOrdos 017000Inner Mongolia Autonomous RegionChina Laboratory of Molecular Medicine Ordos Clinical College of Inner Mongolia Medical UniversityOrdos Central HospitalOrdos 017000Inner Mongolia Autonomous RegionChina Department of Radiology Ordos Clinical College of Inner Mongolia Medical UniversityOrdos Central HospitalOrdos 017000Inner Mongolia Autonomous RegionChina

baCKGROUND Atherosclerosis is one of the main causes of coronary artery ostial lesions seen *** coronary artery ostial lesions are rare,and cases reported previously were associated with syphilitic vasculitis and aortic ***,we report three rare cases of secondary coronary ostial *** to their rareness,these lesions can easily be neglected,which may lead to misdiagnosis and missed *** SUMmaRy We present three patients with acute myocardial infarction and unstable angina caused by secondary coronary artery ostial *** Case 1,coronary angiography(CAG)revealed 90%stenosis of the left main coronary *** contrast computed tomography(CT)suggested thymic carcinoma invading the left main coronary *** artery bypass grafting and tumor resection were *** Case 2,echocardiography revealed a sinus of Valsalva aneurysm(SVA)-like *** showed a right coronary sinus giant aneurysm and complete obstruction of the right coronary artery(RCA)*** contrast CT confirmed these *** Bentall procedure was *** Case 3,CT CAG identified an anomalous origin of the right coronary artery(AORCA)from the left sinus of Valsalva coursing between the aorta and pulmonary trunk,causing severe RCA ostium stenosis by *** correction of the AORCA was *** The cases reported here suggest that we should consider other causes of coronary ostial lesions other than atherosclerosis.

关键词： Coronary artery Ostial lesions Thymic carcinoma Sinus of Valsalva aneurysm Anomalous origin Case report

Optimization of Agrobacterium tumefaciens-Mediated Genetic Transformation of maize

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Phyton-International Journal of Experimental Botany 2022年第2期91卷 363-374页

作者： Mengtong Liu yangyang Zhou Tongyu Liu Jianyu Lu Jing Qu Shuyan Guan yiyong ma College of Life Sciences Jilin Agricultural UniversityChangchun130118China College of Agronomy Jilin Agricultural UniversityChangchun130118China

Immature embryos of inbred maize(Zea mays)lines(H8183,H8184,and H8185)were used for Agrobacterium *** used theβ-glucuronidase gene(GUS)as the target gene and the glufosinate resistance gene(bar)as the selection *** conducted research on several aspects,such as different genotypes,coculture conditions,screening agent concentrations,and concentrations of indole-3-butytric acid(Iba),6-benzylaminopurine(6-ba),and ascorbic acid(Vc)in the differentiation *** optimized the genetic transformation system,and the obtained results indicated that among the three lines studied,the induction rate of H8185 was the highest at 93.2%,followed by H8184,with H8183 having the lowest induction rate(80.1%).The best coculture method was that using the N6 coculture medium layered with a sterile filter *** orthogonal analysis,we found that the optimal combination of the three factors in the differentiation medium was A_(3)(1 mg mL^(−1)Iba),B_(3)C_(1)(1.6 mg mL^(−1)6-ba),and D_(3)(1.5 mg mL^(−1)Vc).Through GUS staining analysis,bar test-strip analysis,and polymerase chain reaction,five transgenic plants were finally *** study established the optimal conditions for genetic transformation in maize.

关键词： maize optimization genetic regeneration immature embryos Agrobacterium-mediated transformation

海洋沉积证据在低纬过程气候变化中的应用及展望

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海洋地质前沿 2024年第2期40卷 1-10页

作者：罗传秀王晓静苏翔马婷杨艺萍杜恕环杨子杰孙玉慧梁诗晴南方海洋科学与工程广东省实验室(广州) 广州511458 中国科学院边缘海与大洋地质重点实验室广州510301 西安科技大学地质与环境学院西安710054 北京师范大学地表过程与资源生态国家重点实验室珠海基地珠海519087 中国科学院大学北京110190

在国内外研究的基础上,对印太暖池区的沃克环流和厄尔尼诺-南方涛动(ENSO)、热带辐合带(ITCZ)等低纬过程的空间分布和随时间的变化规律及其研究方法进行初步归纳,并指出研究中存在的问题。本文论述了厄尔尼诺-南方涛动变率在全新世早期... 详细信息

在国内外研究的基础上,对印太暖池区的沃克环流和厄尔尼诺-南方涛动(ENSO)、热带辐合带(ITCZ)等低纬过程的空间分布和随时间的变化规律及其研究方法进行初步归纳,并指出研究中存在的问题。本文论述了厄尔尼诺-南方涛动变率在全新世早期及中世纪气候异常期(1 000~700 a BP)的晚期逐渐增强,介绍了热带辐合带在ba暖期(B?llingAller?d Warm Period)和前北方期(pre-Boreal,10.3~9.5 ka BP)的北移,以及在新仙女木事件(younger Dryas Event,12.5~11.5 ka BP)和北大西洋冷期(距今7.5~5 ka BP)期间的南移。对低纬过程长时间尺度轨道周期的探讨表明,末次冰盛期赤道东太平洋出现了较偏南的热带辐合带锋面系统,甚至在1.65 ma冰期,热带辐合带也有快速南移的证据。海洋沉积的粒度、黏土矿物、陆源粉尘、元素和同位素、有孔虫分析等研究方法在推测厄尔尼诺-南方涛动和热带辐合带位移中有很好的应用,建议以陆源生态系统对气候的响应为切入点、以孢粉为手段来探讨陆源植被、气候、火灾和海-陆大气环流等低纬过程的变化特征,进而反演沃克环流(或厄尔尼诺-南方涛动)演化和热带辐合带位移的影响。

关键词：暖池区地质时期厄尔尼诺-南方涛动热带辐合带孢粉

琼东南盆地所在区块系列井钻井液侵入损害综合分析及优化

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科学技术与工程 2024年第9期24卷 3663-3674页

作者：张耀元蒋官澄马双政宜镜天贺垠博王冠翔庞俊中海油能源发展股份有限公司工程技术分公司湛江524057 油气资源与探测国家重点实验室北京102249 油气钻完井技术国家工程研究中心北京102249 中国石油大学(北京)石油工程学院北京102249 中国石油大学(北京)石油工程教育部重点实验室北京102249

琼东南盆地属于中孔低渗储层,储层易发生水化、水锁等伤害。当前区块系列井所用深水钻井液侵入损害类型、机理不明,且传统的钻井液伤害评价方法误差大,不能直观地量化损害程度。因此设计了以钻井液污染实验、扫描电子显微镜(scanning el... 详细信息

琼东南盆地属于中孔低渗储层,储层易发生水化、水锁等伤害。当前区块系列井所用深水钻井液侵入损害类型、机理不明,且传统的钻井液伤害评价方法误差大,不能直观地量化损害程度。因此设计了以钻井液污染实验、扫描电子显微镜(scanning electron microscope,SEM)分析、计算机断层扫描(computed tomography,CT)结合的方式分析钻井液固相以及液相侵入损害储层的方法。结果表明,深水钻井液与地层水配伍性良好,储层水锁损害率处于19.8%~31.4%,液相侵入损害主要为水锁损害;岩心SEM扫描结果显示其孔隙连通性差,EDS测试结果中ba^(2+)、Ca^(2+)含量较高,分析固相侵入损害主要由加重剂引起,且蒸馏水返排后岩心CT扫描结果显示孔隙度微幅上升表明固相堵塞很难通过自然返排的方式清除。于是通过研发降滤失剂和优选加重剂粒径配比的手段优化深水钻井液储层保护性能。根据理想充填理论,确定最佳配比为1000目CaCO_(3)、600目CaCO_(3)和200目CaCO_(3)的比例为5∶11∶9。优化后体系滤失量显著降低,固相颗粒中径在90μm左右,滤饼致密程度明显提高;渗透率恢复值提高12.1%~19.68%,对该区块钻井液储层保护性能优化具有指导意义。

关键词：储层损害 CT扫描钻完井水基钻井液规律与程度

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基于粘结性能的高黏改性剂与沥青配伍性研究

新型建筑材料 2024年第3期51卷 76-81,103页

作者：马宏鹏李款潘友强李思齐张健郁嘉栋中路交科科技股份有限公司江苏南京211800 南京航空航天大学土木工程系江苏南京210016

现有黏韧性评估方法使用的金属拉头并不能真实反映沥青与集料的粘结能力,为此提出新的黏韧性评估方法,并以黏韧性、韧性为核心指标对2种高黏改性剂与3种沥青进行配伍性试验。结果表明:改性沥青与高黏改性剂M-9314和HVA的配伍性优于基质... 详细信息

现有黏韧性评估方法使用的金属拉头并不能真实反映沥青与集料的粘结能力,为此提出新的黏韧性评估方法,并以黏韧性、韧性为核心指标对2种高黏改性剂与3种沥青进行配伍性试验。结果表明:改性沥青与高黏改性剂M-9314和HVA的配伍性优于基质沥青,且最佳配伍沥青为I-D改性沥青。当高黏改性剂掺量相同时,改性沥青的黏韧性与高黏改性剂中SBS的含量无关,而与改性沥青中SBS的交联状态有关。同时,集料-沥青粘结评估方法的黏韧性与金属-沥青粘结评估方法的黏韧性存在较好的相关性,且集料-沥青粘结评估方法更接近实际情况,建议集料-沥青粘结评估方法的黏韧性指标为:黏韧性>15 N·m,韧性>10 N·m。

关键词：沥青高黏改性剂配伍性黏韧性韧性拉伸粘结