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Layered Structural PBAT Composite Foams for Efficient Electromagnetic Interference Shielding 被引量:4
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作者 Jianming Yang Hu Wang +2 位作者 Yali Zhang Hexin Zhang Junwei Gu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期273-286,共14页
The utilization of eco-friendly,lightweight,high-efficiency and high-absorbing electromagnetic interference(EMI)shielding composites is imperative in light of the worldwide promotion of sustainable manufacturing.In th... The utilization of eco-friendly,lightweight,high-efficiency and high-absorbing electromagnetic interference(EMI)shielding composites is imperative in light of the worldwide promotion of sustainable manufacturing.In this work,magnetic poly(butyleneadipate-coterephthalate)(PBAT)microspheres were firstly synthesized via phase separation method,then PBAT composite foams with layered structure was constructed through the supercritical carbon dioxide foaming and scraping techniques.The merits of integrating ferroferric oxideloaded multi-walled carbon nanotubes(Fe3O4@MWCNTs)nanoparticles,a microcellular framework,and a highly conductive silver layer have been judiciously orchestrated within this distinctive layered configuration.Microwaves are consumed throughout the process of“absorption-reflection-reabsorption”as much as possible,which greatly declines the secondary radiation pollution.The biodegradable PBAT composite foams achieved an EMI shielding effectiveness of up to 68 dB and an absorptivity of 77%,and authenticated favorable stabilization after the tape adhesion experiment. 展开更多
关键词 Electromagnetic interference shielding layered structure Supercritical carbon dioxide foaming Poly(butyleneadipateco-terephthalate) MICROCELLULAR
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Identification of Phases in Aluminide Coatings by Means of Interference Layer Metallography
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作者 吴维叟 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1989年第5期339-345,共7页
Interference layer metallography was used to identify the phases present in the aluminide coating on superalloy IN738LC. They are: two intermetallic aluminides NiAl and Ni_3Al, y-solid solution and a Cr-rich solid sol... Interference layer metallography was used to identify the phases present in the aluminide coating on superalloy IN738LC. They are: two intermetallic aluminides NiAl and Ni_3Al, y-solid solution and a Cr-rich solid solution, two sulphides M_(23)C_6 and MC, and two sulphides (Al,Cr)_3S_4 and (Cr,Ti)_3S_4. ZnS and ZnSe are proposed to be vapor deposited onto the surface of the specimen to get good colour contrast and good light-dark contrast. The refractive index and absorption coefficient of all these phases have been detemined. 展开更多
关键词 coating interference layer metallography ALUMINIZING optical constants
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Theoretical Study on Quantitative Characterization of Interlayer Interference in Multi-Layer Commingled Production 被引量:1
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作者 Pengfei Mu Shaopeng Wang +2 位作者 Jie Tan Hanqing Zhao Li’an Zhang 《Journal of Power and Energy Engineering》 2021年第4期21-29,共9页
X oilfield is a typical layered reservoir with a large vertical span and many oil-bearing formations. There are significant differences in reservoir types and fluid properties among various formations. The interlayer ... X oilfield is a typical layered reservoir with a large vertical span and many oil-bearing formations. There are significant differences in reservoir types and fluid properties among various formations. The interlayer interference is severe in the development process. At present, the interlayer interference research based on dynamic monitoring data cannot meet development adjustment needs. Combined with the field test results, through the indoor physical simulation experiment method, dynamic inversion method, and reservoir engineering method, this paper analyzes the main control factors and interference mechanism of interlayer interference, studies the variation law of interference coefficient, improves and forms the quantitative characteristic Theory of interlayer interference in multi-layer commingled production, and provides theoretical guidance for the total adjustment of the middle strata division in the oilfield. 展开更多
关键词 Thin Interbedded Reservoir Multi-layer Production Interbedded interference Quantitative Characterization Theoretical Research
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One-pot Synthesis of Bio-inspired Layered Materials of 3D Graphene Network/Calcium Carbonate
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作者 张晶 YAO Bin +7 位作者 PING Hang YU Hongjian ZHANG Fan ZHANG Jinyong WANG Yucheng WANG Hao WANG Weimin 傅正义 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第4期795-799,共5页
A bio-inspired layered material of reduced graphene oxide(RGOs) and calcium carbonate was synthesized via a one-pot strategy in DMF/H2O mixed solvent. The experimental results show that the product is a layered mate... A bio-inspired layered material of reduced graphene oxide(RGOs) and calcium carbonate was synthesized via a one-pot strategy in DMF/H2O mixed solvent. The experimental results show that the product is a layered material of wrinkled RGOs networks and micron-sized calcium carbonate particles with uniform granular diameter and homogeneous morphology, which are distributed between the layered gallery of the graphene scaffold. The polymorph and the morphology of the in-situ produced calcium carbonate particles can be manipulated by simply changing the temperature scheme. Besides, the graphene oxide was reduced to a certain extent, and the hierarchical wrinkles were generated in the RGOs layer by the in-situ formation of the calcium carbonate particles. This work provides a facile and controllable strategy for synthesizing layered material of RGOs and carbonates, and also presents a platform for making three-dimensional porous wrinkled RGOs networks. 展开更多
关键词 bio-inspired layered structure one-pot synthesis graphene calcium carbonate
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Bio-G除臭剂对蛋鸡舍内氨气及产蛋性能的影响 被引量:12
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作者 林英庭 徐玉 +1 位作者 周海波 李文立 《家畜生态》 2002年第2期26-27,共2页
在面积相等 ,饲养密度相近的 2栋蛋鸡舍内连续 1 5 d喷洒 Bio- G除臭剂 ,每天 1次 ,每次 5 L。结果表明 :喷洒 Bio- G后 ,鸡舍氨气含量明显下降 。
关键词 产蛋性能 bio-G除臭剂 蛋鸡 氨气 鸡舍
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Optimum Design for Shrink-fit Multi-layer Vessels under Ultrahigh Pressure Using Different Materials 被引量:6
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作者 YUAN Gexia LIU Hongzhao WANG Zhongrnin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第5期582-589,共8页
Multi-layer pressure vessels are widely used in every field of high pressure technology.For the purpose of enhancing a vessels' load bearing capacity,a beneficial process like shrink-fit is usually employed.However,f... Multi-layer pressure vessels are widely used in every field of high pressure technology.For the purpose of enhancing a vessels' load bearing capacity,a beneficial process like shrink-fit is usually employed.However,few documents on optimum design for multi-layer shrink-fit vessels made of different strength materials can be found,available data are mainly on two-layer vessels.In this paper,an optimum design approach is developed for shrink-fit multi-layer vessels under ultrahigh pressure by using different materials.Maximum shear stress theory is applied as design criteria.The inner and outer radii of a multi-layer vessel,as well as the material of each layer,are assumed to be known.The optimization mathematical model is,thereby,built.Lagrange multipliers method is required to obtain the optimal design formula of wall ratio(ratio of outer to inner radii) of each layer,from which the optimum formulas of shrinkage pressure and radial interference are derived with the superposition principle employed.These formulas are applicable for the optimization design of all multi-layer vessels made of different materials,or same materials.The formulas of the limit working pressure and the contact pressure show that the optimum wall ratio of each layer and limit working pressure are only related to all selected material strength and unrelated to the position of the layer placement in the vessel.However,shrinkage pressure is related to the position of the layer placement in the vessel.Optimization design of an open ended shrink-fit three-layer vessel using different materials and comparisons proved that the optimized multi-layer vessels have outstanding characteristics of small radial interference and are easier for assembly.When the stress of each layer is distributed more evenly and appropriately,the load bearing capability and safety of vessels are enhanced.Therefore,this design is material-saving and cost-effective,and has prospect of engineering application. 展开更多
关键词 multi-layer vessels Lagrange multiplier shrink-fit optimum interference maximum shear stress theory
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Study on Compressible Turbulent Boundary Layer Multiple Shock Wave Interaction in the Duct
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作者 王裕清 《International Journal of Mining Science and Technology》 SCIE EI 1997年第1期78-82,共5页
The structure and trubulence phenomena of multiple shock wave /turbulent boundary layer interaction (MSW-TBLI) in a square duct were investigated using flow visualization methods and a two-component Laser Doppler Velo... The structure and trubulence phenomena of multiple shock wave /turbulent boundary layer interaction (MSW-TBLI) in a square duct were investigated using flow visualization methods and a two-component Laser Doppler Velocimeter (LDV ). First - the MSW-TBLI was visualized by schlieren photography and laser holographic interferography. Second, the time-mean and fluctuating velocities in the MSW-TBLI were explored in detail using LDV Spatial distributions of turbulence intensity,Reynolds shear stress and turbulence kinetic energy are presented. 展开更多
关键词 MULTIPLE shock wave turbullent BOUNDARY layer interference
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基于EMR与V_(eE_peak)组合电参数的IGBT模块封装老化监测
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作者 董超 韦虎俊 +1 位作者 尹金良 杜明星 《太阳能学报》 EI CAS CSCD 北大核心 2024年第11期1-8,共8页
该文提出一种基于电磁辐射干扰(EMR)与V_(eE_peak)组合电参数监测IGBT模块封装老化的方法,旨在监测多种老化同时发生时IGBT模块的健康状态。首先,分析V_(eE_peak)和EMR的产生机理以及模块内部寄生参数对VeE和EMR的影响;其次,分析不同老... 该文提出一种基于电磁辐射干扰(EMR)与V_(eE_peak)组合电参数监测IGBT模块封装老化的方法,旨在监测多种老化同时发生时IGBT模块的健康状态。首先,分析V_(eE_peak)和EMR的产生机理以及模块内部寄生参数对VeE和EMR的影响;其次,分析不同老化对IGBT模块内部寄生参数的影响;最后,结合实验结果证明所提方法的正确性。这是一种不需要复杂监测电路的非侵入式监测方法,可有效降低多种老化耦合对IGBT模块健康状态监测结果产生的误差。 展开更多
关键词 焊料层空洞 IGBT模块 键合线老化 电磁辐射干扰 V_(eE_peak)
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涤纶织物全生物基阻燃抗熔滴涂层的构建
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作者 李好帅 郑兆临 +3 位作者 刘雁雁 王宏阳 罗丽娟 郑振荣 《毛纺科技》 CAS 北大核心 2024年第4期31-37,共7页
为赋予涤纶织物良好的阻燃性能和抗熔滴性能,采用生物质植酸和壳聚糖为原料,通过层层自组装工艺对涤纶织物进行壳聚糖/植酸(CS/PA)全生物基阻燃抗熔滴涂层整理,并对整理前后涤纶织物的表面形貌、阻燃性能、热稳定性、燃烧性能、白度及... 为赋予涤纶织物良好的阻燃性能和抗熔滴性能,采用生物质植酸和壳聚糖为原料,通过层层自组装工艺对涤纶织物进行壳聚糖/植酸(CS/PA)全生物基阻燃抗熔滴涂层整理,并对整理前后涤纶织物的表面形貌、阻燃性能、热稳定性、燃烧性能、白度及其阻燃机制进行分析。结果表明:整理后涤纶织物表面均匀沉积了CS/PA涂层,极限氧指数由21.0%升高至28.3%,具有良好的阻燃性能,在垂直燃烧测试中织物能够自熄且无熔滴,损毁长度由16.0 cm降低为7.6 cm;热稳定性和燃烧性能得到改善,最大热释放速率降低52.0%,总热释放量下降33.3%;CS/PA涂层主要通过膨胀型阻燃机制提高涤纶织物的阻燃性能;整理后涤纶织物白度下降了2.5%,为利用环保和无有机溶剂方法制备全生物基阻燃抗熔滴涤纶织物提供了实验依据。 展开更多
关键词 涤纶 生物基 阻燃 植酸 壳聚糖 层层自组装
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重力流膜生物反应器处理农村污水效能与机制
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作者 马子欣 文敬博 +6 位作者 蒋林巧 柯政 罗娇赢 黄天寅 梁恒 李圭白 唐小斌 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2024年第6期16-24,共9页
重力流膜生物反应器(GDMBR)具有低能耗、低维护和出水稳定的工艺特点,然而,目前关于利用GDMBR直接处理农村污水的相关研究较少,为此,探究GDMBR处理生活污水的通量变化规律、污染物去除效能以及不同膜孔径对其的影响。结果表明,GDMBR处... 重力流膜生物反应器(GDMBR)具有低能耗、低维护和出水稳定的工艺特点,然而,目前关于利用GDMBR直接处理农村污水的相关研究较少,为此,探究GDMBR处理生活污水的通量变化规律、污染物去除效能以及不同膜孔径对其的影响。结果表明,GDMBR处理生活污水时可在无反冲洗条件下长期稳定运行,稳定通量为1.3~1.5 L/(m~2·h)。这是由于膜表面生物滤饼层内形成了疏松多孔结构,且膜孔内污染物含量极低。GDMBR工艺可在较低污泥质量浓度的前提下实现对COD和UV_(254)的高效去除,去除率分别为78%和85%,并有效保留污水中的氮源和磷源。此外,不同膜孔径对GDMBR工艺除污染效能的影响甚微,但微滤膜构成的GDMBR系统的稳定通量略高于超滤膜系统。 展开更多
关键词 重力流膜生物反应器 膜污染 生物滤饼层 膜孔径 农村污水处理
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重力驱动超滤技术处理高浊水的效能及机制研究
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作者 郑成志 姜舒 +5 位作者 孙国胜 王澳 梁恒 罗娇赢 李圭白 唐小斌 《给水排水》 CSCD 北大核心 2024年第5期33-41,共9页
重力驱动超滤工艺(GDM)具有低维护、免清洗等特点,是农村净水的实用技术;然而,季节型高浊/暴雨型高浊给GDM系统稳定性造成了巨大挑战。研究构建了间歇曝气耦合GDM工艺直接过滤高浑浊度水,并探究了GDM工艺长期运行的通量稳定机制和净水... 重力驱动超滤工艺(GDM)具有低维护、免清洗等特点,是农村净水的实用技术;然而,季节型高浊/暴雨型高浊给GDM系统稳定性造成了巨大挑战。研究构建了间歇曝气耦合GDM工艺直接过滤高浑浊度水,并探究了GDM工艺长期运行的通量稳定机制和净水效能。结果表明,GDM工艺可在无反冲洗条件下长期稳定运行,且耦合曝气后显著提升GDM稳定通量(38.81%),对UV254、氨氮、高锰酸盐指数的平均去除率分别达62.22%、31.04%、33.86%。间歇曝气可促使滤饼层变得疏松多孔,提升滤饼层内的微生物多样性,强化了生物滤饼层对污染物的降解效能。因此,GDM工艺可有效应对水源水季节型高浊/暴雨型高浊问题。 展开更多
关键词 重力驱动超滤工艺 高浑浊度 生物滤饼层 膜污染 农村供水
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煤层气直井储层堵塞原因分析及解堵措施应用
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作者 郭晶 张建国 +3 位作者 贾慧敏 王琪 何珊 范秀波 《中国煤层气》 CAS 2024年第3期20-24,共5页
针对煤层气直井储层堵塞后气量难以恢复的问题,开展了储层堵塞原因及恢复措施的研究。通过对煤层气直井储层堵塞成因及生产特征分析,将储层堵塞分为三种类型:层间干扰型、排采不连续型、井间干扰型,针对不同原因导致的储层堵塞在进行压... 针对煤层气直井储层堵塞后气量难以恢复的问题,开展了储层堵塞原因及恢复措施的研究。通过对煤层气直井储层堵塞成因及生产特征分析,将储层堵塞分为三种类型:层间干扰型、排采不连续型、井间干扰型,针对不同原因导致的储层堵塞在进行压裂车解堵时应根据各自的是适应性进行选井和施工,同时尽可能增大措施规模和排量,提高措施见效率和单井产气量。本文提供的压裂车解堵技术,能够有效解决储层堵塞问题,提高储层堵塞井单井产气量。 展开更多
关键词 储层堵塞 压裂车解堵 层间干扰 排采不连续 井间干扰
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天空地多层异构融合网络性能分析及切换协议优化
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作者 周赫 高晓铮 +3 位作者 丁旭辉 李建国 李宗凌 杨凯 《数据采集与处理》 CSCD 北大核心 2024年第1期95-105,共11页
针对多层异构融合网络(Multi-layer heterogeneous integrated network, MLHetINet)切换复杂的问题,提出通过凝视波束及干扰消除算法获取切换分析的有效数据,简化波束对准及捕获过程,扩展空基网络覆盖范围,进而降低跨层切换的复杂度。首... 针对多层异构融合网络(Multi-layer heterogeneous integrated network, MLHetINet)切换复杂的问题,提出通过凝视波束及干扰消除算法获取切换分析的有效数据,简化波束对准及捕获过程,扩展空基网络覆盖范围,进而降低跨层切换的复杂度。首先,针对地面终端和空中基站间的相对高速运动特性,提出空基凝视多波束形成算法,自适应地调整天线相位和权值,在目标方向生成主瓣并对干扰源进行零陷实现空域隔离,简化切换分析的复杂度。然后针对空地信道的复杂性,提出了基于列范数分组排序的多阶干扰消除算法,进一步提高目标信号的检测精度,提高切换分析的准确性。最后,依靠凝视波束技术和干扰消除算法,针对空天地三维多层异构融合网络中的切换事件设计了独立的切换协议,显著降低了网络资源的消耗。仿真结果表明,相较于传统地面网络和天地融合网络,所提波束赋形辅助的天空地多层异构融合网络中的用户信息速率有显著提升。 展开更多
关键词 多层异构融合网络 移动切换分析 波束赋形 干扰消除 切换协议优化
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卫星互联网物理层安全分析研究
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作者 张修锟 韩煜 +1 位作者 王巍 金霖烽 《网络空间安全科学学报》 2024年第4期66-75,共10页
随着卫星互联网的快速发展,如何保证星地通信的安全成为一个不可避免的问题。相比传统的用于通信安全的密钥加密方式,新型并趋于实用的物理层安全技术作为一种新的选择,填补了密钥加密方式的许多不足。其通过充分利用信息传输时的无线... 随着卫星互联网的快速发展,如何保证星地通信的安全成为一个不可避免的问题。相比传统的用于通信安全的密钥加密方式,新型并趋于实用的物理层安全技术作为一种新的选择,填补了密钥加密方式的许多不足。其通过充分利用信息传输时的无线信道特性,为解决现有的安全传输问题提供了新的解决思路。该工作围绕安全通信模型展开,将实际卫星通信场景根据位置关系分为两种情况,从基础理论出发分别综述了在不同条件下采用的物理层安全技术,最后指出了未来安全通信技术的研究方向与面临的挑战。 展开更多
关键词 卫星通信 物理层安全 波束成形 人工噪声 协作干扰
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基于多层次模糊综合评价的多层煤层气合采层位优选研究
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作者 石迎爽 梁冰 薛璐 《煤炭技术》 CAS 2024年第7期10-13,共4页
为了避免或减弱多层煤层气藏合采时的层间干扰现象,选择合适的合采层位至关重要。为此,在综合分析多层煤层气合采层间干扰影响因素基础上,提出了层间干扰性指标,基于多层次模糊综合评价理论,结合已有的煤层气选区评价指标,建立了以资源... 为了避免或减弱多层煤层气藏合采时的层间干扰现象,选择合适的合采层位至关重要。为此,在综合分析多层煤层气合采层间干扰影响因素基础上,提出了层间干扰性指标,基于多层次模糊综合评价理论,结合已有的煤层气选区评价指标,建立了以资源条件、开采条件、层间干扰性为二级指标的多层次指标体系,以及煤层气双层合采模糊综合评价模型。并以H煤层气田为对象,对其不同层位两两组合进行了合采层位优选模糊综合评价,评价结果与实际合采效果相一致。该研究为多层煤层气藏合采层位的优选及成功合采提供了理论支撑。 展开更多
关键词 煤层气 多层合采 层间干扰 模糊综合评价 层位优选
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具有多晶阻挡层的浮空P区IGBT开关特性研究
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作者 肖蝶 冯全源 《电子元件与材料》 CAS 北大核心 2024年第1期67-72,共6页
为了减少浮空P区IGBT结构的栅极空穴积累,改善结构的电磁干扰(EMI)噪声问题,从而提高结构电磁干扰噪声与开启损耗(Eon)之间的折中关系,研究提出了一种具有多晶硅阻挡层的FD-IGBT结构。新结构在传统结构的浮空P区上方引入一块多晶硅阻挡... 为了减少浮空P区IGBT结构的栅极空穴积累,改善结构的电磁干扰(EMI)噪声问题,从而提高结构电磁干扰噪声与开启损耗(Eon)之间的折中关系,研究提出了一种具有多晶硅阻挡层的FD-IGBT结构。新结构在传统结构的浮空P区上方引入一块多晶硅阻挡层,阻挡层接栅极,形成与N型漂移区的电势差。新结构在器件开启过程中,多晶硅阻挡层下方会积累空穴,导致栅极附近积累的空穴数量减少,从而降低浮空P区对栅极的反向充电电流。通过TCAD软件仿真结果表明,相比于传统FD-IGBT,新结构开启瞬态的过冲电流(I_(CE))和过冲电压(V_(GE))的峰值分别下降26.5%和8.6%,且在栅极电阻(R_(g))增加时有更好的电流电压可控性;相同开启损耗下,新结构的dI_(CE)/dt、dV_(CE)/dt和dV_(KA)/dt最大值分别降低26.5%,15.1%和26.1%。 展开更多
关键词 电磁干扰噪声 开启损耗 浮空P区 多晶硅阻挡层 栅极反向充电电流
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BioClay^(TM)prolongs RNA interference-mediated crop protection against Botrytis cinerea 被引量:1
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作者 Jonatan Niño-Sánchez Prabhakaran T.Sambasivam +10 位作者 Anne Sawyer Rachael Hamby Angela Chen Elizabeth Czislowski Peng Li Narelle Manzie Donald M.Gardiner Rebecca Ford Zhi Ping Xu Neena Mitter Hailing Jin 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2022年第11期2187-2198,共12页
One of the most promising tools for the control of fungal plant diseases is spray-induced gene silencing(SIGS).In SIGS,small interfering RNA(siRNA)or double-stranded RNA(dsRNA)targeting essential or virulence-related ... One of the most promising tools for the control of fungal plant diseases is spray-induced gene silencing(SIGS).In SIGS,small interfering RNA(siRNA)or double-stranded RNA(dsRNA)targeting essential or virulence-related pathogen genes are exogenously applied to plants and postharvest products to trigger RNA interference(RNAi)of the targeted genes,inhibiting fungal growth and disease.However,SIGS is limited by the unstable nature of RNA under environmental conditions.The use of layered double hydroxide or clay particles as carriers to deliver biologically active dsRNA,a formulation termed BioClay^(TM),can enhance RNA durability on plants,prolonging its activity against pathogens.Here,we demonstrate that dsRNA delivered as BioClay can prolong protection against Botrytis cinerea,a major plant fungal pathogen,on tomato leaves and fruit and on mature chickpea plants.BioClay increased the protection window from 1 to 3 weeks on tomato leaves and from 5 to 10 days on tomato fruits,when compared with naked dsRNA.In flowering chickpea plants,BioClay provided prolonged protection for up to 4 weeks,covering the critical period of poding,whereas naked dsRNA provided limited protection.This research represents a major step forward for the adoption of SIGS as an eco-friendly alternative to traditional fungicides. 展开更多
关键词 bio Clay double stranded RNA layered double hydroxide RNA interference spray-induced gene silencing
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脉冲Er:YAG激光辐照多层牙齿组织换热特性分析
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作者 王栋 何昭炜 马俊青 《口腔生物医学》 2024年第4期217-222,244,共7页
目的:研究不同激光输入方式下,牙齿组织内部能量的沉积分布特征,搭建激光输入参数与牙齿组织内部温升的定性关系。方法:基于Pennes生物热传导方程,考虑牙齿组织的层状结构以及激光辐照时牙齿外表面与周围环境的热交换,构建Er:YAG激光辐... 目的:研究不同激光输入方式下,牙齿组织内部能量的沉积分布特征,搭建激光输入参数与牙齿组织内部温升的定性关系。方法:基于Pennes生物热传导方程,考虑牙齿组织的层状结构以及激光辐照时牙齿外表面与周围环境的热交换,构建Er:YAG激光辐照牙齿组织的热输运模型。借助有限差分法,对不同激光输入方式下牙齿组织内部温升的时-空分布特征进行了数值模拟和对比分析。结果:激光能量输入方式的改变(脉冲功率、脉宽、脉冲个数、脉冲间隔)对于牙齿组织的温升将产生显著的作用效果,并且其作用效果会随着深度的增加而逐渐衰减;输入总能量一定的前提下,输入方式的作用效果仅集中在照射表面附近,对于组织内部牙髓腔壁面的温升几乎不产生影响。此外,牙齿组织外表面与周围环境的热交换一定程度上抑制牙齿组织的温升并加速其冷却进程。结论:激光输入方式对牙齿组织的温升效果存在重要影响,在其与牙齿组织过程前后需考虑外表面与环境的热交换。 展开更多
关键词 ER:YAG激光 层状牙齿组织 光热效应 Pennes生物热传导方程 表面热交换
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中深层无干扰地岩热供暖系统测试研究
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作者 杨海鸿 马坤 +3 位作者 李学娟 邵继新 管东海 王翠萍 《节能技术》 CAS 2024年第2期164-168,共5页
地热能被誉为面向未来的能源,在我国“双碳战略”背景下其开发利用受到越来越多重视。中深层无干扰地岩热供暖技术具有“封闭换热、对地上地下环境无干扰、自主供热”等特点,近年来已在我国很多地区得到应用。进一步探究该技术在不同地... 地热能被誉为面向未来的能源,在我国“双碳战略”背景下其开发利用受到越来越多重视。中深层无干扰地岩热供暖技术具有“封闭换热、对地上地下环境无干扰、自主供热”等特点,近年来已在我国很多地区得到应用。进一步探究该技术在不同地区的应用特点,对中深层无干扰地岩热技术在宁夏地区的首个应用案例进行测试研究。经测试单口中深层无干扰地岩热换热孔平均输出功率为547.9 kW,连续测试四个月期间热源侧平均供水温度变化范围为33.622.7℃,没有明显的下降;经测试数据分析计算,应用案例年运行成本135662.6元,平均运行单价为1.71元/m^(2)·月;相比于燃煤锅炉供暖方式,年可节约费用517937.4万元,运行单价降低6.53元/m^(2)月,降低幅度达79%;同时年可替代标煤116.3 t,年可减少CO_(2)排放量为288.1 t,具有良好的经济和环保效益。 展开更多
关键词 地热能 中深层无干扰地岩热 供暖系统 运行测试 效益分析
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Grating coupler efficiency enhancement by double layer interference
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作者 Huashan Yang Fuling Zhang +5 位作者 Lemeng Leng Zhaobang Zeng Yue Shao Hui Zhang Nan Yang Xiangning Chen 《Chinese Optics Letters》 SCIE EI CAS CSCD 2019年第3期7-11,共5页
A simple method for improving grating couplers' coupling efficiency without any extra microfabrication processes is proposed. This method can improve the coupling efficiency with 1.69 dB by utilizing the combined ... A simple method for improving grating couplers' coupling efficiency without any extra microfabrication processes is proposed. This method can improve the coupling efficiency with 1.69 dB by utilizing the combined interference in the cladding layer and air gap between the cladding surface and the paralleled angle polished fiber facet. The proposed method can be applied to various kinds of on-chip grating couplers. Back reflection,1 dB bandwidth, and fiber alignment tolerance have also been improved at the same time. 展开更多
关键词 GRATING COUPLER efficiency ENHANCEMENT DOUBLE layer interference
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