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基于Y-shaped路网的早高峰拼车定价策略
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作者 贺冬冬 仲秋雁 曲毅 《系统工程学报》 CSCD 北大核心 2023年第5期706-722,共17页
针对交通资源配置有限导致的早高峰通勤拥堵问题,借鉴共享经济理论,引入拼车出行概念,充分考虑通勤者出行方式和Y-shaped路网特点,建立了基于通勤者出行效益的拼车定价模型.模型结合费用补偿机制,讨论了以平台利润最大化和系统负效用最... 针对交通资源配置有限导致的早高峰通勤拥堵问题,借鉴共享经济理论,引入拼车出行概念,充分考虑通勤者出行方式和Y-shaped路网特点,建立了基于通勤者出行效益的拼车定价模型.模型结合费用补偿机制,讨论了以平台利润最大化和系统负效用最小化为目标的拼车定价策略,并给出了定价策略有效的阈值条件.研究结果表明,当通勤者都参与到拼车服务中时,拼车平台利润和交通系统负效用在其相应拼车定价策略下均能达到最优值,并且以交通系统负效用最小化为目标的拼车定价策略能消除Y-shaped路网中瓶颈处的交通拥堵. 展开更多
关键词 动态拼车 y-shaped瓶颈模型 拼车定价 早高峰通勤
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Gastrotracheal fistula:Treatment with a covered self-expanding Y-shaped metallic stent 被引量:2
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作者 Fei Wang Hong Yu +4 位作者 Ming-Hui Zhu Quan-Peng Li Xian-Xiu Ge Jun-Jie Nie Lin Miao 《World Journal of Gastroenterology》 SCIE CAS 2015年第3期1032-1035,共4页
A 67-year-old man had a sev-ere cough and pulmonary infection for 1 wk before seeking evaluation at our hospital.He had undergone esophagectomy with gastric pull-up and radiotherapy for esophageal cancer 3 years previ... A 67-year-old man had a sev-ere cough and pulmonary infection for 1 wk before seeking evaluation at our hospital.He had undergone esophagectomy with gastric pull-up and radiotherapy for esophageal cancer 3 years previously.After admission to our hospital,gastroscopy and bronchoscopy revealed a fistulous communication between the posterior tracheal wallnear the carina and the upper residual stomach.We measured the diameter of the trachea and bronchus and determined the site and size of the fistula using multislice computed tomography and gastroscopy.A covered self-expanding Y-shaped metallic stent was implanted into the trachea and bronchus.Subsequently,the fistula was closed completely.The patient tolerated the stent well and had good palliation of his symptoms. 展开更多
关键词 Gastrotracheal FISTULA y-shaped metallic STENT ESO
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Y-shaped block copolymers of poly(ethylene glycol) and poly(N-isopropylacrylamide) synthesized by ATRP 被引量:2
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作者 Xin De Tang Xiao Chao Liang Nian Feng Han 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第11期1353-1356,共4页
Novel Y-shaped block copolymers of poly(ethylene glycol) and poly(N-isopropylacrylamide), PEG-b-(PNIPAM)2, were successfully synthesized through atom transfer radical polymerization (ATRP). A difunctional macr... Novel Y-shaped block copolymers of poly(ethylene glycol) and poly(N-isopropylacrylamide), PEG-b-(PNIPAM)2, were successfully synthesized through atom transfer radical polymerization (ATRP). A difunctional macroinitiator was prepared by esterification of 2,2-dichloroacetyl chloride with poly(ethylene glycol) monomethyl ether (PEG). The copolymers were obtained via the ATRP ofN-isopropylacrylamide (NIPAM) at 30℃ with CuCl/Me6TREN as a catalyst system and DMF/H2O (v/v = 3:1) mixture as solvent. The resulting copolymers were characterized by gel permeation chromatography (GPC) and ^1H NMR. These block copolymers show controllable molecular weights and narrow molecular weight distributions (PDI 〈 1.15). Their phase transition temperatures and the corresponding enthalpy changes in aqueous solution were measured by differential scanning calorimetry (DSC). As a result, the phase transition temperature of PEG45-b-(PNIPAM55)2 is higher than that of PNIPAM, however, the corresponding enthalpy change is much lower, indicating the significant influence of the macromolecular composition and architecture on the phase transition. 展开更多
关键词 y-shaped Block copolymer Poly(ethylene glycol) Poly(N-isopropylacrylamide) Atom transfer radical polymerization (ATRP)
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Binary collision approximation for solitary waves in a Y-shaped granular chain
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作者 陈琼 杨先清 +2 位作者 赵新印 王振辉 赵跃民 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期350-355,共6页
We implement a binary collision approximation to study solitary wave propagation in a two-dimensional double Y- shaped granular chain. The solitary wave was transmitted and reflected when it met the interface of the b... We implement a binary collision approximation to study solitary wave propagation in a two-dimensional double Y- shaped granular chain. The solitary wave was transmitted and reflected when it met the interface of the bifurcated branches of the Y-shaped granular chains. We obtain the analytic results of the ratios of the transmitted and reflected speeds to the incident speed of the solitary wave, the maximum force between the two neighbor beads in a solitary wave, and the total time taken by the pulse to pass through each branch. All of the analytic results are in good agreement with the experimental observations from Daraio et al. [Phys. Rev. E 82 036603 (2010)]. Moreover, we also discuss the delay effects on the arrival of split pulses, and predict the recombination of the split waves traveling in branches in the final stem of asymmetric systems. The prediction of pulse recombination is verified by our numerical results. 展开更多
关键词 y-shaped granule chain solitary wave binary collision approximation
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Evaluation of ultimate bearing capacity of Y-shaped vibro-pile
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作者 王新泉 陈永辉 +2 位作者 林飞 卢孝益 张霆 《Journal of Central South University》 SCIE EI CAS 2008年第S2期186-194,共9页
Based on Mindlin stress solution, a numerical computational method was proposed to calculate the stresses in the ground induced by side friction and the resistance of Y-shaped vibro-pile. The improved Terzaghi's a... Based on Mindlin stress solution, a numerical computational method was proposed to calculate the stresses in the ground induced by side friction and the resistance of Y-shaped vibro-pile. The improved Terzaghi's and ЪерезанцевВГ's methods for ultimate bearing capacity evaluation were proposed by considering the stress strength induced by friction resistance at pile head level of Y-pile. A new method to calculate the ultimate bearing capacity of Y-pile was also proposed based on the assumptions of soil failure mode at the tip of Y-pile and the use of Mohr-Coulomb soil yield criterion and Vesic compressive correction coefficient with the induced stresses in the ground. Based on the comparisons with the field static load test results, it is found that the improved Terzaghi's method gives higher ultimate capacity, while the other two methods shows good agreement with the field results. 展开更多
关键词 y-shaped vibro-pile circular PILE MINDLIN stress solution ULTIMATE bearing capacity of PILE TIP static loading test
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Transfer characteristics of dynamic biochemical signals in non-reversing pulsatile flows in a shallow Y-shaped microfluidic channel: signal filtering and nonlinear amplitude-frequency modulation
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作者 Zongzheng CHEN Weimo YUAN +4 位作者 A.R.AZIZ Zhengming GAO Depei ZENG Bo LIU Kairong QIN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第10期1481-1496,共16页
The transports of the dynamic biochemical signals in the non-reversing pulsatile flows in the mixing microchannel of a Y-shaped microfluidic device are ana- lyzed. The results show that the mixing micro-channel acts a... The transports of the dynamic biochemical signals in the non-reversing pulsatile flows in the mixing microchannel of a Y-shaped microfluidic device are ana- lyzed. The results show that the mixing micro-channel acts as a low-pass filter, and the biochemical signals are nonlinearly modulated by the pulsatile flows, which depend on the biochemical signal frequency, the flow signal frequency, and the biochemical signal transporting distance. It is concluded that, the transfer characteristics of the dynamic biochemical signals, which are transported in the time-varying flows, should be carefully considered for better loading biochemical signals on the cells cultured on the bottom of the microfluidic channel. 展开更多
关键词 shallow y-shaped microfluidic channel dynamic biochemical signal non-reversing pulsatile flow nonlinear amplitude-frequency modulation Taylor-Aris disper-sion
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Y-Shaped Intra-Scleral Fixated Lens versus Retro-Pupillary Iris Claw Lens in the Treatment of Aphakia
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作者 Ahmed Mohamed Morshed Mahmoud Nasr Aldeeb +1 位作者 Adel Kamal Abdeen Salah Mohamed Almosalamy 《Open Journal of Ophthalmology》 2019年第2期105-124,共20页
Background: Many reasons can lead to an aphakia without adequate capsular support for implantation of a posterior chamber intraocular lens (IOL), such as intraoperative unintentional rupture of posterior capsule durin... Background: Many reasons can lead to an aphakia without adequate capsular support for implantation of a posterior chamber intraocular lens (IOL), such as intraoperative unintentional rupture of posterior capsule during phacoemulsification, planned intracapsular cataract extraction, ocular trauma and lens dislocation due to congenital and acquired causes. Purpose: To compare Y-shaped intra-scleral fixation of a posterior chamber IOL with retro pupillary fixation of an iris-claw intraocular lens (IOL) for Aphakic eyes without sufficient capsular support as respects safety, visual recovery and complications of both methods. Patients and Methods: One hundred Aphakic eyes were arbitrarily distributed between two groups. Group A included 50 eyes treated with retropupillary fixation of iris claw lens and group B included 50 eyes treated with Y-shaped intra-scleral fixation technique. Preoperative, intraoperative and postoperative data were analysed including best corrected visual acuity (BCVA), intraocular pressure (IOP), surgical time, intraoperative problems, IOL malposition and postoperative complications. Following up on patients was carried out for at least six months. Results: The mean duration of surgery was 21 ± 5.3 min in group A and was 53.4 ± 6.9 min in group B (p-value 0.05). IOL tilt was found in 0 (0%) eyes in group A and in 5 (10%) eyes in group B (p 0.05). Conclusion: The results of our study indicated that both methods are satisfactory in correcting aphakia without sufficient capsular support as regards postoperative best corrected visual acuity (BCVA);however the surgical technique of retropupillary iris claw lens is easier, shorter, with low intra- and postoperative complications and safer than those used for intra-scleral fixation of IOL. But for eyes which lack both iris and capsular support, a scleral fixation of a posterior chamber IOL remains the only option. 展开更多
关键词 APHAKIA Iris-Claw Intraocular LENS (IOL) y-shaped INTRA Scleral Fixation
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Comparison of lag screws and double Y-shaped miniplates in the fixation of anterior mandibular fractures
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作者 Lydia Melek 《World Journal of Methodology》 2021年第3期88-94,共7页
BACKGROUNDMandibular fractures constitute about 80.79% of maxillofacial injuries inAlexandria University, either as isolated mandibular fractures or as a part ofpanfacial fractures. The combination of symphyseal and p... BACKGROUNDMandibular fractures constitute about 80.79% of maxillofacial injuries inAlexandria University, either as isolated mandibular fractures or as a part ofpanfacial fractures. The combination of symphyseal and parasymphyseal fracturesrepresent 47.09% of the total mandibular fractures.AIMTo compare the effectiveness of lag screws vs double Y-shaped miniplates in thefixation of anterior mandibular fractures.METHODSThis study is a prospective randomized controlled clinical trial, performed onsixteen patients with anterior mandibular fractures. Patients were divided equallyinto two groups, each consisting of eight patients. Group 1: Underwent openreduction and internal fixation using two lag screws. Group 2: Underwent openreduction and internal fixation using double Y-shaped plates. The followingparameters were assessed: operating time in minutes, pain using a visual analogscale, edema, surgical wound healing for signs and symptoms of infection,occlusion status and stability, maximal mouth opening, and sensory nervefunction. Cone beam computed tomography was performed at 3 and 6 mo tomeasure bone density and assess the progression of fracture healing.RESULTSThe study included 13 males (81.3%) and 3 females (18.8%) aged 26 to 45 years(mean age was 35.69 ± 6.01 years). The cause of trauma was road traffic accidentsin 10 patients (62.5%), interpersonal violence in 3 patients (18.8%) and othercauses in 3 patients (18.8%). The fractures comprised 10 parasymphyseal fractures(62.5%) and 6 symphyseal fractures (37.5%). The values of all parameters were comparable in both groups with no statistically significant difference except forthe mean bone density at 3 mo postoperatively which was 946.38 ± 66.29 in group 1 and 830.36 ± 95.53 in group 2 (P = 0.015).CONCLUSIONBoth lag screws and double Y-shaped miniplates provide favorable means offixation for mandibular fractures in the anterior region. Fractures fixed with lagscrews show greater mean bone density at 3 mo post-operation, indicative ofhigher primary stability and faster early bone healing. Further studies with largersample sizes are required to verify these conclusions. 展开更多
关键词 Anterior mandibular fractures Symphyseal fracture Parasymphyseal fracture MINIPLATES Lag screws Double y-shaped plates
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六斑平颜蚜蝇雄虫对雌性腺化合物的触角电位和行为反应
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作者 李彦如 史丽 +2 位作者 韩海斌 刘爱萍 陈国泽 《环境昆虫学报》 CSCD 北大核心 2024年第3期718-726,共9页
初步探究肉苁蓉Cistanche deserticola蛀茎蝇—六斑平颜蚜蝇Eumerus seximaculatum雌虫性腺化合物的主要成分并对其生物活性进行检测,为六斑平颜蚜蝇的生物防治提供理论依据。本研究采用气相色谱-质谱联用(GC-MS)技术对雌性腺化合物进... 初步探究肉苁蓉Cistanche deserticola蛀茎蝇—六斑平颜蚜蝇Eumerus seximaculatum雌虫性腺化合物的主要成分并对其生物活性进行检测,为六斑平颜蚜蝇的生物防治提供理论依据。本研究采用气相色谱-质谱联用(GC-MS)技术对雌性腺化合物进行分析鉴定,根据雄成虫的触角电位(EAG)及行为反应对各组分进行筛选、分析及确定。在雌性腺化合物中共鉴定出31种挥发性物质,从中选取5种,设置5个浓度梯度,进行EAG测试。结果表明,雄成虫对5种物质不同浓度的EAG反应敏感性差异明显。其中,雄成虫对1μg/mL 1,4-丁二醇二甲基丙烯酸酯、100μg/mL邻苯二甲酸二异丁酯最为敏感;把对雄虫引诱率最高的1,4-丁二醇二甲基丙烯酸酯和邻苯二甲酸二异丁酯按照不同体积比混合后开展行为选择试验,结果显示,当两者比例为1∶3时,对雄虫的引诱率最高,可达60%以上。综上所述,1,4-丁二醇二甲基丙烯酸酯和邻苯二甲酸二异丁酯被认为是雌虫性信息素的重要成分,对雄虫有明显的引诱作用,为苁蓉蛀茎蝇性诱剂的开发奠定理论基础。 展开更多
关键词 性信息素 蚜蝇科 平颜蚜蝇属 GC-MS EAG Y型嗅觉仪
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3种植物源物质复配对异囊地蛛的驱避作用
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作者 韦道奎 裴洲洋 +6 位作者 唐庆峰 李晨 张丽娜 朱启法 许大凤 王芳 周本国 《安徽农业科学》 CAS 2024年第13期114-116,共3页
[目的]寻找烟田蜘蛛卵囊类异物防控新方法。[方法]采用Y型嗅觉仪法和滤纸药膜法研究3-甲基二十烷、桉油烯醇和野菊花精油3种植物源物质复配对异囊地蛛选择行为的影响。[结果]3-甲基二十烷、桉油烯醇和野菊花精油3种植物源物质不同体积... [目的]寻找烟田蜘蛛卵囊类异物防控新方法。[方法]采用Y型嗅觉仪法和滤纸药膜法研究3-甲基二十烷、桉油烯醇和野菊花精油3种植物源物质复配对异囊地蛛选择行为的影响。[结果]3-甲基二十烷、桉油烯醇和野菊花精油3种植物源物质不同体积比复配对异囊地蛛均具有很好的驱避作用,其中体积比8∶2∶3的驱避效果最好,达91.67%,且72 h内均有显著驱避效果。[结论]3-甲基二十烷、桉油烯醇和野菊花精油3种植物源物质复配作为高效植物源驱避剂防治烟田蜘蛛卵囊类异物具有应用前景。 展开更多
关键词 植物源物质 异囊地蛛 Y型嗅觉仪 滤纸药膜法 驱避作用
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顺-3-己烯醇乙酸酯对大蜡螟的驱避作用
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作者 连雅琴 付童 +4 位作者 李一然 刘巧 周令霞 门丽娜 张志伟 《山西农业科学》 2024年第1期131-136,共6页
利用植物挥发物监测和调控害虫行为已逐渐成为害虫绿色防控的重要途径。顺-3-己烯醇乙酸酯广泛存在于瓜果及绿色植物的叶片中,具有环境友好、无残留的优点。大蜡螟是养蜂产业中常见的害虫,严重影响蜂产业和蜜蜂资源保护。为生产中应用顺... 利用植物挥发物监测和调控害虫行为已逐渐成为害虫绿色防控的重要途径。顺-3-己烯醇乙酸酯广泛存在于瓜果及绿色植物的叶片中,具有环境友好、无残留的优点。大蜡螟是养蜂产业中常见的害虫,严重影响蜂产业和蜜蜂资源保护。为生产中应用顺-3-己烯醇乙酸酯调控大蜡螟的行为控制其对蜂群的危害提供依据,为开发新型昆虫行为调控剂以及大蜡螟的绿色防控提供支持,利用Y-型嗅觉仪研究大蜡螟不同虫态的个体对不同浓度、同一浓度不同剂量顺-3-己烯醇乙酸酯的行为趋性。结果表明,大蜡螟幼虫对顺-3-己烯醇乙酸酯表现出显著的负趋性,浓度为0.5 mol/L时,大蜡螟幼虫总选择率为79.33%,并表现为极显著的负趋性;雄成虫对顺-3-己烯醇乙酸酯的选择率为8.33%,具有显著的负趋性;不同剂量的顺-3-己烯醇乙酸酯对大蜡螟成虫的选择行为影响不显著,但对幼虫均具有明显的驱避效果。 展开更多
关键词 顺-3-己烯醇乙酸酯 行为趋性 Y-型嗅觉仪 大蜡螟 驱避
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杏壳木醋液对马铃薯瓢虫的非特异性作用
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作者 甘杨广 叶乐夫 +4 位作者 李振宇 王莉青 池阳 徐臻 付雪 《中国农学通报》 2024年第13期121-128,共8页
探究杏壳木醋液对马铃薯瓢虫的生长抑制、拒食活性以及驱避活性影响,明确杏壳木醋液对马铃薯瓢虫的非特异性作用,为马铃薯瓢虫绿色防控和木醋液的害虫防治应用提供理论依据。用杏壳木醋液不同浓度处理的龙葵叶片喂食马铃薯瓢虫,测定不... 探究杏壳木醋液对马铃薯瓢虫的生长抑制、拒食活性以及驱避活性影响,明确杏壳木醋液对马铃薯瓢虫的非特异性作用,为马铃薯瓢虫绿色防控和木醋液的害虫防治应用提供理论依据。用杏壳木醋液不同浓度处理的龙葵叶片喂食马铃薯瓢虫,测定不同浓度处理在各时间段4龄幼虫的体重增长量、成虫和幼虫的非选择性和选择性取食量以及行为选择情况,并分析不同浓度杏壳木醋液对马铃薯瓢虫的增重抑制、拒食活性、驱避活性等影响。结果表明,4龄幼虫的体重增加、成虫和幼虫的非选择性和选择性取食量以及行为选择均显著受到杏壳木醋液的影响,其中杏壳木醋液在48 h时4龄幼虫体重增长抑制率最高达到83%;4龄幼虫和成虫的最高非选择性拒食率分别为92%和82%;最高选择性拒食率分别为87%和78%;马铃薯瓢虫幼虫和成虫在四臂嗅觉仪中均表现出了极显著的驱避作用,幼虫的最高驱避指数为0.67,成虫为0.95。杏壳木醋液对马铃薯瓢虫有显著的增重抑制、拒食活性和驱避活性,杏壳木醋液浓度对马铃薯瓢虫还有显著的非特异性作用。 展开更多
关键词 马铃薯瓢虫 木醋液 生长抑制 拒食作用 驱避作用 四臂嗅觉仪
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Sensitive and Specific Y-Shaped Ratio Biosensor for Detecting Serum mi R-18a:Potential Early Scanning Tool for Non-Small Cell Lung Cancer
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作者 Fei Yu Yue Wang +2 位作者 Caiyuan Yu Wei Zhang Xuefeng Bai 《Journal of Analysis and Testing》 EI CSCD 2024年第2期237-244,共8页
miR-18a has been identified as a significantly expressed microRNA(miRNA)in non-small cell lung cancer(NSCLC)and plays a vital role in cancer cell transformation,metastasis,and carcinogenesis.Herein,a pair of binary pr... miR-18a has been identified as a significantly expressed microRNA(miRNA)in non-small cell lung cancer(NSCLC)and plays a vital role in cancer cell transformation,metastasis,and carcinogenesis.Herein,a pair of binary probes from numerous probe pairs based on single nucleotide polymorphism analyses of miR-18a and miR-18b was first designed and screened to develop a Y-shaped ratio biosensor for accurate detection of serum miR-18a in NSCLC.The special structure of the binary probes combined with the hairpin showed strong specificity for miR-18a,which was confirmed by polyacrylamide gel electrophoresis assay and square wave voltammetry assay.Furthermore,it is beneficial to immobilize single-stranded DNA(ssDNA)probes due to the large specific surface area of nanoporous gold,thereby improving the sensitivity of the biosensor.The Y-shaped ratio biosensor exhibited a wide detection range and can quantify the concentration of miR-18a in the range of 10 fmol/L–100 pmol/L,with a limit of detection of 0.211 fmol/L(S/N=3).Moreover,it exhibits excellent detection capabilities in serum samples since the biosensor showed a high selectivity toward the coexistence of miR-18a and miR-18b.Therefore,the prepared Y-shaped ratio biosensor is a highly sensitive and specific miR-18a detection tool,capable of identifying microscopic amounts of miR-18a in serum samples,providing great potential for early screening of NSCLC. 展开更多
关键词 Nanoporous gold y-shaped biosensor miR-18a NSCLC
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Valley transport in Kekulé structures of graphene
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作者 王娟娟 汪军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期44-53,共10页
Valleytronics is an emergent discipline in condensed matter physics and offers a new way to encode and manipulate information based on the valley degree of freedom in materials. Among the various materials being studi... Valleytronics is an emergent discipline in condensed matter physics and offers a new way to encode and manipulate information based on the valley degree of freedom in materials. Among the various materials being studied, Kekulé distorted graphene has emerged as a promising material for valleytronics applications. Graphene can be artificially distorted to form the Kekulé structures rendering the valley-related interaction. In this work, we review the recent progress of research on Kekulé structures of graphene and focus on the modified electronic bands due to different Kekulé distortions as well as their effects on the transport properties of electrons. We systematically discuss how the valley-related interaction in the Kekulé structures was used to control and affect the valley transport including the valley generation, manipulation, and detection. This article summarizes the current challenges and prospects for further research on Kekulé distorted graphene and its potential applications in valleytronics. 展开更多
关键词 GRAPHENE y-shaped Kekulé(Y-Kek)lattice distortion structure O-Kekulé(O-Kek)structure valley current
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化橘红精油香气成分分析及品质检测
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作者 谭岸 陈杵生 +3 位作者 马雨茵 吴迪 阚启鑫 宋明月 《现代食品科技》 CAS 北大核心 2024年第7期203-210,共8页
为了阐明化橘红精油中挥发性有机物成分,探究化橘红精油关键香气成分,建立化橘红精油质量控制标准。该研究采用水蒸气蒸馏法提取化橘红精油,采用感官评价,结合电子鼻和气相-质谱联用仪(GC-MS)以及气相-质谱联用仪(GC-MS/O)明确化橘红中... 为了阐明化橘红精油中挥发性有机物成分,探究化橘红精油关键香气成分,建立化橘红精油质量控制标准。该研究采用水蒸气蒸馏法提取化橘红精油,采用感官评价,结合电子鼻和气相-质谱联用仪(GC-MS)以及气相-质谱联用仪(GC-MS/O)明确化橘红中关键香气成分,同时评估其农药残留。结果发现:通过感官评价发现化橘红主要的挥发性风味以柑橘味、甜香味、药味、木质味、辛辣味为代表性特征,通过GC-MS从化橘红精油共检测出68种挥发性有机物,其中主要的挥发性有机物烯烃类、醇类和酯类分别占比84.48%、6.67%和6.05%,以柠檬烯,月桂烯、γ-松油烯为主要的挥发性有机物,结合GC-MS/O确定其15种关键性的挥发性特征香气成分。结合农残分析,明确水蒸气蒸馏提取下化橘红精油有机氯农药残留符合药典规定标准。该研究清晰阐明了化橘红精油挥发性有机物组成和品质安全,为化橘红产品开发和品质控制提供参考。 展开更多
关键词 化橘红 精油 气相-质谱联用仪(GC-MS) 气相色谱嗅闻仪(GC-MS/O) 农药残留
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Theory and Experimental Verification on Valveless Piezoelectric Pump with Multistage Y-shape Treelike Bifurcate Tubes 被引量:6
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作者 HUANG Jun ZHANG Jianhui +1 位作者 XUN Xianchao WANG Shouyin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第3期462-468,共7页
Among most traditional piezo water cooling systems, piezoelectric valve pumps are adopted as their driving sources. The valves in these pumps induce problems of shock and vibration and also make their structure compli... Among most traditional piezo water cooling systems, piezoelectric valve pumps are adopted as their driving sources. The valves in these pumps induce problems of shock and vibration and also make their structure complicated, which is uneasy to minimize and reduce their reliability and applicability of the whole system. In order to avoid these problems caused by valve structure, a novel valveless piezoelectric pump is developed, which integrates both functions of transforming and cooling. The pump’s Y-shape tree-like construction not only increases the efficiency of cooling but also the system reliability and applicability. Firstly, a multistage Y-shape treelike bifurcate tube is proposed, then a valveless piezoelectric pump with multistage Y-shape treelike bifurcate tubes is designed and its working principle is analyzed. Then, the theoretical analysis of flow resistance characteristics and the flow rate of the valveless piezoelectric pump are performed. Meanwhile, commercial software CFX is employed to perform the numerical simulation for the pump. Finally, this valveless piezoelectric pump is fabricated, the relationship between the flow rates and driving frequency, as well as the relationship between the back pressure and the driving frequency are experimentally investigated. The experimental results show that the maximum flow rate is 35.6 mL/min under 100 V peak-to-peak voltage (10.3 Hz) power supply, and the maximum back pressure is 55 mm H2O under 100 V (9 Hz) power supply, which validates the feasibility of the valveless piezoelectric pump with multistage Y-shape treelike bifurcate tubes. The proposed research provides certain references for the design of valveless piezoelectric pump and improves the reliability of piezo water cooling systems. 展开更多
关键词 PIEZOELECTRIC PUMP valveless y-shape tube treelike bifurcate
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Analysis of the Flow Rate Characteristics of Valveless Piezoelectric Pump with Fractal-like Y-shape Branching Tubes 被引量:7
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作者 HUANG Jun ZHANG Jianhui +1 位作者 WANG Shouyin LIU Weidong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第3期628-634,共7页
Microchannel heat sink with high heat transfer coefficients has been extensively investigated due to its wide application prospective in electronic cooling. However, this cooling system requires a separate pump to dri... Microchannel heat sink with high heat transfer coefficients has been extensively investigated due to its wide application prospective in electronic cooling. However, this cooling system requires a separate pump to drive the fluid transfer, which is uneasy to minimize and reduces their reliability and applicability of the whole system. In order to avoid these problems, valveless piezoelectric pump with fractal-like Y-shape branching tubes is proposed. Fractal-like Y-shape branching tube used in microchannel heat sinks is exploited as no-moving-part valve of the valveless piezoelectric pump. In order to obtain flow characteristics of the pump, the relationship between tube structure and flow rate of the pump is studied. Specifically, the flow resistances of fractal-like Y-shape branching tubes and flow rate of the pump are analyzed by using fractal theory. Then, finite element software is employed to simulate the flow field of the tube, and the relationships between pressure drop and flow rate along merging and dividing flows are obtained. Finally, valveless piezoelectric pumps with fractal-like Y-shape branching tubes with different fractal dimensions of diameter distribution are fabricated, and flow rate experiment is conducted. The experimental results show that the flow rate of the pump increases with the rise of fractal dimension of the tube diameter. When fractal dimension is 3, the maximum flow rate of the valveless pump is 29.16 mL/min under 100 V peak to peak (13 Hz) power supply, which reveals the relationship between flow rate and fractal dimensions of tube diameter distribution. This paper investigates the flow characteristics of valveless piezoelectric pump with fractal-like Y-shape branching tubes, which provides certain references for valveless piezoelectric pump with fractal-like Y-shape branching tubes in application on electronic chip cooling. 展开更多
关键词 PIEZOELECTRIC PUMP valveless fractal-like y-shape branching tube
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Flow around three rectangular cylinders arranged in connected and separated Y-shape
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作者 Zhifu Gu Yan Li 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第4期336-341,共6页
Characteristics of cross flow around three rectangular cylinders with two aspect ratios of breadth to width arranged in connected and separated Y-shape at various angles of incident flow were studied by means of force... Characteristics of cross flow around three rectangular cylinders with two aspect ratios of breadth to width arranged in connected and separated Y-shape at various angles of incident flow were studied by means of force measurement in a wind tunnel. Flow visualizations with smoke-wire technique for typical cases were also given. Different types of flow patterns were formed for individual models at different angles of incident flow. From the results of fluctuating velocity measurement in the wake, features of vibration were determined. It shows that as the wind blows along the lines of one limb or rectangular cylinder of the model, oscillation is weak, whereas when the wind blows along the bisector lines of two limbs or cylinders, strong vibration is observed. It is associated with the regular vortex shedding. 展开更多
关键词 Rectangular cylinders. Vortex-induced vibration Flow visualization y-shape
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亚洲玉米螟对球孢白僵菌分生孢子和芽生孢子-玉米共生体的取食选择和嗅觉反应
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作者 隋丽 路杨 +3 位作者 谢敏 邹晓威 李启云 张正坤 《昆虫学报》 CAS CSCD 北大核心 2023年第11期1482-1489,共8页
【目的】球孢白僵菌Beauveria bassiana在植物内定殖,能够间接对植食性昆虫产生不利影响。本研究旨在明确亚洲玉米螟Ostrinia furnacalis初孵幼虫和3龄幼虫取食选择和嗅觉反应行为对分生孢子(aerial conidia,AC)和芽生孢子(blastospore,... 【目的】球孢白僵菌Beauveria bassiana在植物内定殖,能够间接对植食性昆虫产生不利影响。本研究旨在明确亚洲玉米螟Ostrinia furnacalis初孵幼虫和3龄幼虫取食选择和嗅觉反应行为对分生孢子(aerial conidia,AC)和芽生孢子(blastospore,BS)类型球孢白僵菌-玉米共生体的响应。【方法】每株玉米接种球孢白僵菌孢子悬液(1.0×10^(8)个孢子/mL)20 mL,采用灌根法构建球孢白僵菌-玉米共生体,包括球孢白僵菌AC处理组和BS处理组。采用培养皿叶碟法测试亚洲玉米螟初孵幼虫和3龄幼虫在取食选择性和非选择性条件下对AC和BS处理组球孢白僵菌-玉米共生体玉米叶片的取食选择率;利用Y型嗅觉仪测试亚洲玉米螟初孵幼虫和3龄幼虫对AC和BS处理组球孢白僵菌-玉米共生体玉米叶片的嗅觉选择系数和嗅觉选择反应率。【结果】培养皿叶碟法测试结果表明,在选择性和非选择性条件下亚洲玉米螟初孵幼虫和3龄幼虫对AC和BS处理组球孢白僵菌-玉米共生体玉米叶片的取食选择率均低于对照组;在选择性条件下,亚洲玉米螟初孵幼虫对BS处理组球孢白僵菌-玉米共生体玉米叶片的取食选择率最低;在非选择性条件下,AC和BS处理组间亚洲玉米螟初孵幼虫对球孢白僵菌-玉米共生体玉米叶片的取食选择率差异不显著。Y型嗅觉仪测试结果表明,亚洲玉米螟初孵幼虫和3龄幼虫对AC和BS处理组球孢白僵菌-玉米共生体玉米叶片的嗅觉选择反应率(嗅觉反应系数<0)均显著低于对照组(嗅觉反应系数>0),显示两种孢子类型球孢白僵菌定殖玉米叶片对亚洲玉米螟幼虫均具有负趋性。【结论】本研究明确了分生孢子和芽生孢子型球孢白僵菌定殖玉米叶片对亚洲玉米螟幼虫取食行为和嗅觉行为均具有驱避性,为利用球孢白僵菌内生定殖生态调控害虫提供理论依据。 展开更多
关键词 亚洲玉米螟 虫生真菌 植物内生性 行为反应 叶碟法 Y型嗅觉仪
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冷杉梢斑螟对寄主植物挥发物行为反应 被引量:1
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作者 周俊华 邢亚 +3 位作者 宇佳 贾妮娅 解丹 迟德富 《东北林业大学学报》 CAS CSCD 北大核心 2023年第4期80-88,共9页
利用苏玛罐顶空吸附法和GC-MS方法,分析了健康红松和被害红松的主梢与球果中挥发性物质种类及峰面积比;挑选其中峰面积比高,危害后变化大的红松挥发物进行触角电位仪法测定,测定了冷杉梢斑螟触角对11种寄主挥发物的反应强度,筛选出8种... 利用苏玛罐顶空吸附法和GC-MS方法,分析了健康红松和被害红松的主梢与球果中挥发性物质种类及峰面积比;挑选其中峰面积比高,危害后变化大的红松挥发物进行触角电位仪法测定,测定了冷杉梢斑螟触角对11种寄主挥发物的反应强度,筛选出8种反应值较高的挥发物,进行了不同浓度梯度对触角反应影响探索,从中选出7种化合物开展了不同浓度下,Y型嗅觉仪中对雌雄成虫行为影响的研究。红松中峰面积比较高的挥发物质有α-蒎烯、3-蒈烯、双戊烯和β-蒎烯。主梢被危害后α-水芹烯、萜品烯和(1R)-(+)-α蒎烯峰面积比上升;球果被危害后β-蒎烯的峰面积比提升;然而主梢与球果被危害后3-蒈烯、月桂烯和双戊烯的峰面积比下降。触角电位测试结果表明:双戊烯、桧烯、对二乙基苯、萜品烯(γ-松油烯)、(1R)-(+)-α蒎烯、(+)-3-蒈烯和D-柠檬烯等7种挥发物在1 mol·L^(-1)的浓度下均能引起雌雄成虫较强的触角电位反应(p<0.05);10^(-1)mol·L^(-1)苯乙烯能引起雌雄成虫较强的触角电位反应(p<0.05)。但8种寄主植物挥发物引起的触角电位反应值在雌虫和雄虫之间有显著差异。Y型嗅觉仪中行为测试结果表明:双戊烯、桧烯、(1R)-(+)-α-蒎烯和D-柠檬烯对冷杉梢斑螟雌雄成虫都有较强的引诱作用;萜品烯(γ-松油烯)和(+)-3-蒈烯对冷杉梢斑螟雌雄成虫都有较强的驱避作用。对二乙基苯对雌虫有较高的驱避性,对雄虫有较高的引诱性。8种寄主植物挥发物可以引起冷杉梢斑螟触角电生理反应,且对雌雄冷杉梢斑螟影响效果不同;双戊烯、桧烯、(1R)-(+)-α-蒎烯和D-柠檬烯可以作为冷杉梢斑螟雌雄成虫引诱剂成分,萜品烯(γ-松油烯)和(+)-3-蒈烯可以作为冷杉梢斑螟成虫驱避剂成分。 展开更多
关键词 冷杉梢斑螟 寄主植物挥发物 GC-MS分析 触角电位 Y型嗅觉仪
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