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射频等离子体改性制备S_(2.O_(2.-8/SnO_(2.-Al_(2.O_(3)固体超强酸催化剂的研究

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现代化工 2024年第7期44卷 139-144页

作者：张旭东李秀兰朱长辉田保河朱文超四川轻化工大学机械工程学院四川宜宾644005 国民核生化灾害防护国家重点实验室北京102205

采用低温陈化法制备S_(2.O_(2.-8/SnO_(2.-Al_(2.O_(3)固体超强酸催化剂,利用射频等离子体技术对其进行改性后催化L-酪氨酸与甲醇的酯化反应。利用Hammett指示剂法、XRD、HRTEM、BET、FT-IR、Py-IR和NH_(3)-TPD等对改性前后的催化剂进... 详细信息

采用低温陈化法制备S_(2.O_(2.-8/SnO_(2.-Al_(2.O_(3)固体超强酸催化剂,利用射频等离子体技术对其进行改性后催化L-酪氨酸与甲醇的酯化反应。利用Hammett指示剂法、XRD、HRTEM、BET、FT-IR、Py-IR和NH_(3)-TPD等对改性前后的催化剂进行表征。结果表明,经射频等离子体改性后的催化剂颗粒分散性更好、粒径更小(4.32.nm)、比表面积更大(104.4 m^(2./g)、总酸量更高(142.9μmol/g)。在温度为180℃、压力为1 MPa的条件下,射频等离子体改性后的催化剂催化L-酪氨酸甲酯化反应6 h后L-酪氨酸甲酯产率可达92.。

关键词：固体超强酸 S_(2.O_(2.-8/SnO_(2.-Al_(2.O_(3) 射频等离子体酯化反应

基于时频域特征参数的风电机组滚动轴承故障诊断方法及应用

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内蒙古电力技术 2024年第3期42卷 13-19页

作者：张利慧李殊瑶李晓波俎海东云杰魏超内蒙古电力(集团)有限责任公司内蒙古电力科学研究院分公司呼和浩特010020

针对风电机组滚动轴承工作环境恶劣、工况多变且振动信号成分复杂等特点,将33项时域和频域特征参数及其特性应用于风电机组滚动轴承状态监测和故障诊断中,利用奇异值分解重构法(Singular Value Decomposition,SVD)将滚动轴承振动故障信... 详细信息

针对风电机组滚动轴承工作环境恶劣、工况多变且振动信号成分复杂等特点,将33项时域和频域特征参数及其特性应用于风电机组滚动轴承状态监测和故障诊断中,利用奇异值分解重构法(Singular Value Decomposition,SVD)将滚动轴承振动故障信号中的噪声等干扰成分去除,降噪重构后的信号经过基于经验模式分解法(Empirical Mode Decomposition,EMD)的希尔伯特-黄变换,实现故障冲击信号的共振解调处理,将低频周期故障调制信号筛选出来,最终结合滚动轴承各部件故障特征频率、振动信号时频分析结果和时频特征参数诊断结果实现滚动轴承的状态监测和故障识别。并通过振动测试信号分析,验证了该方法对提取风电机组滚动轴承故障特征的有效性。

关键词：风电机组时域特征参数频域特征参数滚动轴承振动监测故障诊断特征提取

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香菇与木霉互作方式及绿霉病防治研究进展

食用菌学报 2024年第3期31卷 113-124页

作者：李丰硕冀宝营韩冰王洪奇孙立梅孙佳妮韩朝辽宁省微生物科学研究院辽宁朝阳122000 辽宁省生态环境监测中心辽宁沈阳110165 中国铁路沈阳局集团有限公司沈阳林业管理所辽宁沈阳110100

木霉属(Trichoderma spp.)病原菌诱发的绿霉病,是香菇(Lentinula edodes)栽培过程中常见的病害之一。木霉属病原菌不仅可污染培养料,与香菇菌丝竞争营养和生存空间,而且可感染香菇菌丝体,引起香菇菌棒腐烂,造成严重的经济损失。笔者综... 详细信息

木霉属(Trichoderma spp.)病原菌诱发的绿霉病,是香菇(Lentinula edodes)栽培过程中常见的病害之一。木霉属病原菌不仅可污染培养料,与香菇菌丝竞争营养和生存空间,而且可感染香菇菌丝体,引起香菇菌棒腐烂,造成严重的经济损失。笔者综述引起香菇绿霉病的木霉种类,香菇和木霉的互作方式,绿霉病的防治方法,香菇抗木霉能力,以及木霉感染真菌病毒的相关研究,期望为香菇绿霉病的防治提供参考。

关键词：香菇绿霉病木霉属互作方式防治

Critical thresholds for stage division of water erosion process in different ridge systems in mollisol region of Northeast China

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Journal of Mountain Science 2023年第6期20卷 1540-1560页

作者： JIAO Jian QIN Wei li Kun-heng XU Hai-chao YIN Zhe HOU Shu-yan State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China Research Center on Soil and Water Conservation of the Ministry of Water Resources Beijing 100048China School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China Heilongjiang Province Hydropower Research Institute Harbin 150070China

Extreme rainfall events on a slope under ridge tillage systems cause concentrated stream soil *** analyse the critical thresholds for different stages of water erosion process of ridge systems,simulated rainfall-erosion experiments for the contour wide ridge(CWR),contour narrow ridge(CNR),longitudinal wide ridge(LWR),and longitudinal narrow ridge(LNR)were conducted under four rainfall intensities,with slope gradients of 3°and 5°.For the runoff event,the runoff depth order was LNR>LWR>CWR>CNR;the soil loss order was CNR>LNR>CWR>*** product of slope factor(S)and rainfall erosivity(R)or runoff depth(D),can be adopted as critical thresholds for different stages of runoff and soil erosion *** the longitudinal ridge systems,R values were provided for LWR and LNR and were the beginning of sheet flow,whereas the product of rainfall erosivity and slope factor(RS)values were provided for LWR and LNR as the beginning of the accelerated concentrated *** the contour ridge systems,R values were provided for CWR and CNR as critical thresholds for the beginning of *** product of runoff depth and slope factor(DS)values were 9.98 and 7.73 mm for CWR and CNR,respectively,and were critical thresholds for the beginning of ridge failure;the DS values were 18.45 and 12.75 mm for CWR and CNR,respectively,and were critical thresholds for the beginning of the formation of ephemeral gully *** critical thresholds can distinguish different stages of soil erosion process modelling.

关键词： Runoff Soil loss Threshold Ridge failure Artificial rainfall simulation

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黄芪花的饲用安全性评价

饲料研究 2024年第2期47卷 89-95页

作者：于侃超李慧马德志刘吉成崔莹张可勇齐齐哈尔医学院科研处黄芪产业研究院黑龙江齐齐哈尔161006

为了评价黄芪花的饲用安全性,根据食品安全国家标准对黄芪花进行急性经口毒性试验、Ames致突变试验、哺乳动物红细胞微核试验、小鼠精母细胞染色体畸变试验以及90 d亚慢性毒性试验。结果表明,大鼠和小鼠在灌胃黄芪花14 d后均未出现明显... 详细信息

为了评价黄芪花的饲用安全性,根据食品安全国家标准对黄芪花进行急性经口毒性试验、Ames致突变试验、哺乳动物红细胞微核试验、小鼠精母细胞染色体畸变试验以及90 d亚慢性毒性试验。结果表明,大鼠和小鼠在灌胃黄芪花14 d后均未出现明显中毒和死亡情况,黄芪花急性经口毒性试验中大鼠和小鼠最大耐受量LD_(50)大于2..00 g/kg BW。采用黄芪花提取物进行3项遗传毒性试验,结果表明,黄芪花提取物未能引起受试菌株发生回复突变,对小鼠红细胞含微核细胞率无影响,对染色体异常细胞率、常染色体单价体和性染色体单价体无影响。90 d经口毒性试验显示,不同黄芪花剂量组喂养下大鼠的增重、总进食量及食物利用率无显著变化,大鼠血液指标和脏器重量均无明显毒理学变化,解剖及组织学观察也未见明显病理组织学变化,未观察到有害作用剂量为1.2. g/kg BW。研究表明,黄芪花安全性高,无致突变性及亚急性毒性,在试验剂量下安全无毒。

关键词：黄芪花安全性评价遗传试验急性毒性试验亚慢性毒性试验

维普期刊数据库博看期刊

Shortening the delivery time of proton therapy by real-time compensation method with raster scanning

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Nuclear Science and Techniques 2022年第6期33卷 62-74页

作者： Xiang-Shang Sun Yong-Jiang li Jun-Ya liu Wen-Tao liao chao Wu Yue-Hu Pu Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai APACTRON Particle Equipment Co. LtdShanghai 201800China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Medical Equipment Innovation Research Center West China HospitalSichuan UniversityChengdu 610041China

Among the various scanning techniques, spot and raster scanning are the most frequently adopted. Raster scanning turns off the beam only when each isoenergy slice irradiation is completed. This feature intrinsically solves the leakage dose and frequent beam-switching problems encountered during spot scanning. However, to shorten the delivery time of raster scanning, a sophisticated dose control strategy is required to guarantee dose *** this study, a real-time compensation method with raster scanning for synchrotron systems was designed. It is characterized by a small spot-spacing planning strategy and real-time subtraction of the transient number of particles delivered between two planning-spot positions from the planned number of particles of the subsequent raster *** efficacy of the compensation method was demonstrated by performing accurate raster scanning simulations with an in-house simulation code and accurate final dose evaluations with a commercial treatment planning *** the similar dose evaluation criteria under a practical high scanning speed, compared with the spot scanning method, the total delivery time of the compensated raster scanning method was significantly shortened by 53.3% in the case of irradiating a cubical target and by 2..8% in a pelvic case. Therefore, it can be concluded that real-time compensated raster scanning with a fast scanning configuration can significantly shorten the delivery time compared to that of spot scanning. It is important to reduce the pressure on patients caused by prolonged immobilization and to improve patient throughput capacity at particle therapy centers.

关键词： Proton therapy Raster scanning Delivery time Scanning simulation

Near-infrared light switching nitric oxide nanogenerator with“linkage mechanism”for tumor targeting multimodal synergistic therapy

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Science China Chemistry 2023年第2期66卷 586-600页

作者： Wei Zhang Qize Xuan Qi Zhang Tong Wang Chen Wang Hui li chao Chen Ping Wang State Key Laboratory of Bioreactor Engineering Biomedical Nanotechnology CenterSchool of BiotechnologyEast China University of Science and TechnologyShanghai200237China Institute for Environmental Pollution and Health School of Environmental and Chemical EngineeringShanghai UniversityShanghai200444China Department of Bioproducts and Biosystems Engineering University of MinnesotaSt PaulMN55108USA

Gaseous therapy based on nitric oxide(NO),as a potential anti-tumor treatment strategy,has attracted great attention,but the targeted and controlled gas release in the tumor site still remains a *** addressing these difficulties,a near-infrared(NIR)light-triggered NO release nanogenerator with a“linkage mechanism”was designed on the basis of sodium nitroprussidedoped mesoporous Prussian blue nanoparticles,in which the outer structure was modified with p H-sensitive gatekeeper chitosan and tumor-targeting agent folic ***“linkage mechanism”can achieve precise release of NO under the control of photothermal effect at tumor site,which can couple photothermal therapy and gas therapy to address the premature release of gas during ***,the amount of released gas can be controlled by adjusting the irradiation time and laser ***,as-fabricated nanocomposites hold high photothermal conversion efficiency under NIR laser irradiation,resulting in the on-demand release of NO and chemotherapy *** released NO can inhibit the expression of hypoxiainducible factorα(HIF-1α)and alleviate the hypoxic tumor microenvironment,thereby enhancing the efficacy of ***,in vitro and in vivo experiments exhibited remarkable antitumor efficiency,and the synergistic gas/chemo/photothermal therapy of deep tumors was *** findings indicate an effective strategy to stimulate further the development of deep tumor therapy,which may provide new insights into other NO-related medical applications.

关键词： NO generator NIR-trigger NO release linkage mechanism gas therapy targeted synergistic therapy

Stress corrosion cracking behavior of PH13-8Mo stainless steel in Cl^- solutions

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Journal of Iron and Steel Research International 2017年第3期24卷 282-289页

作者： Qiang Yu chao-fang Dong Jian-xiong liang Zhen-bao liu Kui Xiao Xiao-gang li Corrosion and Protection Center Institute of Advanced Materials and Technology University of Science and Technology Beijing Beijing 100083 China Institute for Special Steel Central Iron and Steel Research Institute Beijing 100081 China

The stress corrosion cracking（ SCC） behavior of PH13-8Mo precipitation hardening stainless steel（ PHSS） in neutral NaCl solutions was investigated through slow-strain-rate tensile（ SSRT） test at various applied potentials. Fracture morphology,elongation ratio,and percentage reduction of area were measured to evaluate the SCC susceptibility. A critical concentration of 1. 0 mol / L neutral NaCl existed for SCC of PH13-8Mo steel. Significant SCC emerged when the applied potential was more negative than -0. 15 VSCE,and the SCC behavior was controlled by an anodic dissolution（ AD） *** the applied potential was lower than -0. 55 VSCE,an obvious hydrogen-fracture morphology was observed,which indicated that the SCC behavior was controlled by hydrogen-induced cracking（ HIC）.Between -0. 15 and -0. 35 VSCE,the applied potential exceeded the equilibrium hydrogen evolution potential in neutral NaCl solutions and the crack tips were of electrochemical origin in the anodic region; thus,the SCC process was dominated by the AD mechanism.

关键词： Stress corrosion cracking PH13-8Mo precipitation hardening stainless steel Neutral NaCl solution Slow-strain-rate tensile test Applied potential

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高熵超导体研究进展

科学通报 2024年第20期69卷 2951-2963页

作者：曾令勇李宽李龙夫余沛峰王康旺陈睿张超项载琛石磊张云蔚江恺瑶罗惠霞中山大学材料科学与工程学院广州510006 中山大学光电材料与技术国家重点实验室广州510006 中山大学广东省磁电物性分析与器件重点实验室广州510006 中山大学聚合物复合材料及功能材料教育部重点实验室广州510006 中山大学物理学院广州510275 澳门城市大学数据科学学院中国澳门999078

高熵材料是近年来许多领域研究的一类新型材料,高熵的原理为材料的设计和性能定制提供了更大的自由度.高熵材料主要有高熵合金和高熵陶瓷.自2.14年第一个高熵超导体被发现以来,超导电性一直是高熵材料领域的研究热点之一.人们在一些高... 详细信息

高熵材料是近年来许多领域研究的一类新型材料,高熵的原理为材料的设计和性能定制提供了更大的自由度.高熵材料主要有高熵合金和高熵陶瓷.自2.14年第一个高熵超导体被发现以来,超导电性一直是高熵材料领域的研究热点之一.人们在一些高熵超导体中观察到了许多奇特的物性,如高压下超导转变温度T_(c)基本保持不变、极强电声耦合的超导电性、能带结构中存在狄拉克点等.然而,高熵超导材料的研究才刚刚开始,仍存在许多未知.另外,元素组成和平均价电子数对高熵超导体的T_(c)起着重要作用.高熵合金的超导行为似乎不同于常规合金超导体、铜氧化物超导体、铁基超导体和非晶体超导体,表明它们可以视为一类单独的超导体.结合高熵材料的优异力学和物理性能,高熵超导体有望在极端条件下服役.本文简要介绍了高熵合金超导体、高熵陶瓷超导体和高熵超导体薄膜的最新研究进展,并对高熵超导体进行了初步的展望.我们相信在高熵超导材料这一研究领域将会发现许多新的物理现象.

关键词：超导电性拓扑能带高熵合金高熵陶瓷高熵薄膜