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A modified simulated annealing algorithm and an excessive area model for floorplanning using fixed-outline constraints 被引量:5
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作者 De-xuan ZOU gai-ge WANG +1 位作者 gai PAN Hong-wei QI 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2016年第11期1228-1244,共17页
Outline-free floorplanning focuses on area and wirelength reductions, which are usually meaningless, since they can hardly satisfy modern design requirements. We concentrate on a more difficult and useful issue, fixed... Outline-free floorplanning focuses on area and wirelength reductions, which are usually meaningless, since they can hardly satisfy modern design requirements. We concentrate on a more difficult and useful issue, fixed-outline floorplanning. This issue imposes fixed-outline constraints on the outline-free floorplanning, making the physical design more interesting and challenging. The contributions of this paper are primarily twofold. First, a modified simulated annealing(MSA) algorithm is proposed. In the beginning of the evolutionary process, a new attenuation formula is used to decrease the temperature slowly, to enhance MSA's global searching capacity. After a period of time, the traditional attenuation formula is employed to decrease the temperature rapidly, to maintain MSA's local searching capacity. Second, an excessive area model is designed to guide MSA to find feasible solutions readily. This can save much time for refining feasible solutions. Additionally, B*-tree representation is known as a very useful method for characterizing floorplanning. Therefore, it is employed to perform a perturbing operation for MSA. Finally, six groups of benchmark instances with different dead spaces and aspect ratios—circuits n10, n30, n50, n100, n200, and n300—are chosen to demonstrate the efficiency of our proposed method on fixed-outline floorplanning. Compared to several existing methods, the proposed method is more efficient in obtaining desirable objective function values associated with the chip area, wirelength, and fixed-outline constraints. 展开更多
关键词 Fixed-outline floorplanning Modified simulated annealing algorithm Global search Excessive area model B*-tree representation
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Efficacy of the combination of modern medicine and traditional Chinese medicine in pulmonary fibrosis arising as a sequelae in convalescent COVID-19 patients: a randomized multicenter trial 被引量:6
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作者 Zhen-Hui Lu Chun-Li Yang +7 位作者 gai-ge Yang Wen-Xu Pan Li-GuangTian Jin-Xin Zheng Shan Lv Shao-Yan Zhang Pei-Yong Zheng Shun-Xian Zhang 《Infectious Diseases of Poverty》 SCIE 2021年第2期107-108,共2页
Background:The coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)has led to a significant number of mortalities worldwide.COVID-19 poses a serious threat to human l... Background:The coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)has led to a significant number of mortalities worldwide.COVID-19 poses a serious threat to human life.The clinical manifestations of COVID-19 are diverse and severe and 20%of infected patients are reported to be in a critical condition.A loss in lung function and pulmonary fibrosis are the main manifestations of patients with the severe form of the disease.The lung function is affected,even after recovery,thereby greatly affecting the psychology and well-being of patients,and significantly reducing their quality of life. 展开更多
关键词 COVID-19 SA5R-CoV-2 Pulmonary fibrosis Modern medicine Traditional Chinese medicine
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Enhancement of Light Absorption in Thin Film Silicon Solar Cells with Metallic Grating and One-Dimensional Photonic Crystals 被引量:5
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作者 ZHENG gai-ge XIAN Feng-Lin LI Xiang-Yin 《Chinese Physics Letters》 SCIE CAS CSCD 2011年第5期151-154,共4页
We design an effective light trapping scheme through engineering metallic gratings and one-dimensional dielectric photonic crystals(PhCs)to increase the optical path length of light within the solar cells.This incorpo... We design an effective light trapping scheme through engineering metallic gratings and one-dimensional dielectric photonic crystals(PhCs)to increase the optical path length of light within the solar cells.This incorporation can result in broadband optical absorption enhancement not only for transverse magnetic polarized light but also for transverse-electric polarization.Even when no plasmonic mode can be excited,due to the high reflection of the PhCs,the absorption in the active region can still be enhanced.Rigorous coupled wave analysis results demonstrate that such a hybrid structure boosts the overall cell performance by increasing the light trapping capabilities and is especially effective at the silicon band edge.This kind of design can be used to increase the optical absorption over a wide spectral range and is relatively independent of the angle of incidence. 展开更多
关键词 ABSORPTION TRAPPING TRANSVERSE
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PGC-1α differentially regulates the mRNA expression profiles of genes related to myofiber type specificity in chicken 被引量:5
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作者 SHAN Yan-ju JI gai-ge +5 位作者 ZOU Jian-min ZHANG Ming TU Yun-jie LIU Yi-fan JU Xiao-jun SHU Jing-ting 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第8期2083-2094,共12页
Previous studies on mammals showed that peroxisome proliferator-activated receptor gamma coactivator-1α(PGC-1α)played a prominent role in regulating muscle fiber type transition and composition.However,the role of P... Previous studies on mammals showed that peroxisome proliferator-activated receptor gamma coactivator-1α(PGC-1α)played a prominent role in regulating muscle fiber type transition and composition.However,the role of PGC-1αin chicken muscle has seldom been explored.To investigate the effect of PGC-1αon chicken skeletal muscles in this study,the PGC-1αgene was overexpressed or silenced in chicken primary myoblasts by using lentivirus,and then the effects of the PGC-1αgene overexpression and knockdown on the mRNA expression profile of genes related to myofiber type specificity were examined during fiber formation.The results showed that overexpression of PGC-1αfrom proliferation to differentiation was accompanied by the up-regulated expression of Pax7,MyoD,and CnAα,which was significantly(P<0.01)increased after one day of transfection(1 I).The enhancement of MyoG,MEF2 c,and MyHC SM expression lagged,which was improved significantly(P<0.01)after four days of transfection(1 I3 D).Overexpression of PGC-1αdecreased(P<0.01)the MyHC FWM expression after four days of transfection(1 I3 D),and it had no significant impact(P>0.05)on the expression of CnB1,NFATc3,and MyHC FRM during myofiber formation.The effective silence(P<0.01)of PGC-1αby lentivirus mediating short hairpin RNA(shRNA)was detected after four days of transfection(1 I3 D)in cultures,and the lack of its function in chicken primary myoblasts significantly(P<0.01)down-regulated the expression of Pax7,MyoD,CnAα,MyoG,MEF2 c,and MyHC SM,significantly(P<0.01)up-regulated the expression of MyHC FWM,and had no significant impact(P>0.05)on the expression of CnB1,NFATc3,and MyHC FRM.These results indicated that the role of PGC-1αin regulating the fiber type specificity of chicken skeletal muscles might be similar to that in mammals,which interplayed with key genes related to myocyte differentiation and calcineurin signaling pathway. 展开更多
关键词 PGC-1αgene CHICKEN myofiber type specificity mRNA expression profile
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Construction of the Plasmid Reference Molecule for Detection of Transgenic Soybean MON89788 被引量:4
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作者 李飞武 邵改革 +7 位作者 邢珍娟 李葱葱 夏蔚 张明 Fei-wu gai-ge Zhen-juan Cong-cong 《Agricultural Science & Technology》 CAS 2010年第5期55-58,86,共5页
[Objective] The aim was to construct a plasmid reference molecule (PRM) for detection of transgenic soybean MON89788. [Method] the lectin gene sequence,3'-junction and 5'-junction sequence between host plant D... [Objective] The aim was to construct a plasmid reference molecule (PRM) for detection of transgenic soybean MON89788. [Method] the lectin gene sequence,3'-junction and 5'-junction sequence between host plant DNA integrated DNA of MON89788 soybean were amplified independently,and the three fragments were cloned into the cloning vector pMD18-T in order through molecular manipulation method to construct pMD-LM3M5,the applicability of the constructed novel PRM was tested. [Result] Sequencing confirmation result showed that the PRM was 3 700 bp in length,containing 1 029 bp of recombined DNA fragment. The limits of qualitative detection of the PRM were 10 copies. [Conclusion] The PRM constructed in this study was suitable for the identification of MON89788 event. 展开更多
关键词 Genetically modified organisms Plasmid reference molecule MON89788 soybean Event-specific detection
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Use of transcriptome sequencing to explore the effect of CSRP3 on chicken myoblasts 被引量:1
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作者 SHAN Yan-ju JI gai-ge +5 位作者 ZHANG Ming LIU Yi-fan TU Yun-jie JU Xiao-jun SHU Jing-ting ZOU Jian-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第4期1159-1171,共13页
The mechanisms that regulate the specificity and maintenance of chicken muscle fiber types remain largely unknown. In mammals, CSRP3 has been shown to play a vital role in the maintenance of typical muscle structure a... The mechanisms that regulate the specificity and maintenance of chicken muscle fiber types remain largely unknown. In mammals, CSRP3 has been shown to play a vital role in the maintenance of typical muscle structure and function. This study investigated the role that CSRP3 plays in chicken skeletal muscle. First, the antibody against chicken CSRP3 protein was prepared, and the expression levels of the mRNA and protein of the CSRP3 gene in four chicken skeletal muscles with different myofiber compositions were compared. Then the effects of CSRP3 silencing on the expression profile of chicken myoblast transcriptomes were analyzed. The results showed that the expression levels of the mRNA and protein of the CSRP3 gene were both associated with the composition of fiber types in chicken skeletal muscles. A total of 650 genes with at least 1.5-fold differences(Q<0.05) were identified, of which 255 genes were upregulated and 395 genes were downregulated by CSRP3 silencing. Functional enrichment showed that several pathways, including adrenergic signaling in cardiomyocytes, adipocytokine signaling pathway and apelin signaling pathway, were significantly(P<0.05) enriched both in differentially expressed genes and all expressed genes. The co-expressed gene network suggested that CSRP3 silencing caused a compensatory upregulation(Q<0.05) of genes related to the assembly of myofibrils, muscle differentiation, and contraction. Meanwhile, two fast myosin heavy chain genes(MyH1B and MyH1E)were upregulated(Q<0.05) upon CSRP3 silencing. These results suggested that CSRP3 plays a crucial role in chicken myofiber composition, and affects the distribution of chicken myofiber types, probably by regulating the expression of MyH1B and MyH1E. 展开更多
关键词 CSRP3 CHICKEN myofiber type transcriptome sequencing
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Confinement of Bloch surface waves in a graphene-based one-dimensional photonic crystal and sensing applications 被引量:2
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作者 Xiu-Juan Zou gai-ge Zheng Yun-Yun Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期198-203,共6页
Bloch surface waves(BSWs) are excited in one-dimensional photonic crystals(Ph Cs) terminated by a graphene monolayer under the Kretschmann configuration. The field distribution and reflectance spectra are numerica... Bloch surface waves(BSWs) are excited in one-dimensional photonic crystals(Ph Cs) terminated by a graphene monolayer under the Kretschmann configuration. The field distribution and reflectance spectra are numerically calculated by the transverse magnetic method under transfer-matrix polarization, while the sensitivity is analyzed and compared with those of the surface plasmon resonance sensing method. It is found that the intensity of magnetic field is considerably enhanced in the region of the terminated layer of the multilayer stacks, and that BSW resonance appears only in the interface of the graphene and solution. Influences of the graphene layers and the thickness of a unit cell in Ph Cs on the reflectance are studied as well. In particular, by analyzing the performance of BSW sensors with the graphene monolayer,the wavelength sensitivity of the proposed sensor is 1040 nm/RIU whereas the angular sensitivity is 25.1°/RIU. In addition,the maximum of figure of merit can reach as high as 3000 RIU^-1. Thus, by integrating graphene in a simple Kretschmann structure, one can obtain an enhancement of the light–graphene interaction, which is prospective for creating label-free,low-cost and high-sensitivity optical biosensors. 展开更多
关键词 optical sensor Bloch surface wave (BSW) photonic crystal (PhC)
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Enhanced nitrogen removal at low temperature with mixed anoxic/oxic process
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作者 Xiang-kun Li Ying-jun Yang +2 位作者 gai-ge Liu Dou-dou Sun Xiao-chen Ma 《Water Science and Engineering》 EI CAS CSCD 2023年第1期67-75,共9页
Different hydraulic retention times(HRTs)were tested in a mixed anoxic/oxic(A/O)system at 5C and 10C to investigate the effects of HRT and carrier on nitrogen removal in wastewater at low temperatures.The results show... Different hydraulic retention times(HRTs)were tested in a mixed anoxic/oxic(A/O)system at 5C and 10C to investigate the effects of HRT and carrier on nitrogen removal in wastewater at low temperatures.The results showed that the addition of the fillers improved the treatment effect of each index in the system.With an optimal HRT of 7.5 h at 5C,the removal efficiencies of NHþ4-N and total nitrogen(TN)reached 91.2%and 75.6%,respectively.With an HRT of 6 h at 10C,the removal efficiencies of NHþ4-N and TN were 96.7%and 82.9%,respectively.The results of high-throughput sequencing showed that the addition of the suspended carriers in the aerobic zone could improve the treatment efficiency of nitrogen at low temperatures.The microbial analysis indicated that the addition of the suspended carriers enhanced the enrichment of nitrogen removal bacteria.Nitrospira,Nitrotoga,and Nitrosomonas were found to be the bacteria responsible for nitrification,and their relative concentrations on the biofilm at 5C and 10C accounted for 98.11%,92.79%,and 69.98%of all biological samples,respectively. 展开更多
关键词 Domestic sewage Low temperature Mixed A/O process Nitrogen removal Bacterial community structure
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Concentration sensor with multilayer thin film-coupled surface plasmon resonance 被引量:1
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作者 Bao Sen Li Hong-jing ZHENG gai-ge 《Optoelectronics Letters》 EI 2021年第5期289-293,共5页
A concentration sensor based on silver(Ag)/silica(SiO2)/zirconium anhydride(ZrO2)multilayer structure is proposed.Two dominant dips can be observed in the reflection spectrum,which correspond to different sensing meth... A concentration sensor based on silver(Ag)/silica(SiO2)/zirconium anhydride(ZrO2)multilayer structure is proposed.Two dominant dips can be observed in the reflection spectrum,which correspond to different sensing methods.Firstly,it is demonstrated that the coupling between the surface plasmon polariton(SPP)mode and a planar waveguide mode(WGM)leads to the Fano resonance(FR).The induced bonding hybridized modes have ultra-narrow full wave at half maximum(FWHM)as well as ultra-high quality factors(Q).We can achieve a theoretical value of the refractive index sensitivity 167 times higher than conventional surface plasmon resonance(SPR)sensors with a single metal layer.Secondly,the waveguide coupling mode was examined by measuring angular spectra.A deep and sharp waveguide coupling dip was obtained.The experimental results show that with an increase in the concentration of the fill dielectric material in the surface of the system,the resonance dip exhibits a remarkable red shift,and the measured angular sensitivity is 98.04°/RIU. 展开更多
关键词 WGM SiO SPP Concentration sensor with multilayer thin film-coupled surface plasmon resonance
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Migration behavior of solid fuel particles during granulation process and its influence on combustion property
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作者 Zhi-yun Ji Yi-fan Wang +9 位作者 Xiao-hui Fan gai-ge Zhao Min Gan Le-yun Tang Yong Tu Xiao-long Wang Hao-xiang Zheng Xu-ling Chen Xiao-xian Huang Zeng-qing Sun 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2023年第11期2153-2162,共10页
Iron ore sintering process is the main CO_(2) emission source throughout the integrate steelworks,which primarily comes from the combustion of solid fuels.Improving the combustion efficiency and reducing the solid fue... Iron ore sintering process is the main CO_(2) emission source throughout the integrate steelworks,which primarily comes from the combustion of solid fuels.Improving the combustion efficiency and reducing the solid fuel consumption are important ways to reduce the CO_(2) emission in the sintering process.Around the efficient combustion of fuel,the migration behavior and combustion characteristics of solid fuel in the granulation process were investigated.The results indicated that during the granulation process,fuel particles with size less than 0.5 mm mainly migrated into the granules with grain size of 1-3,3-5 and 5-8 mm;fuel particles with size of 0.5^(-1)mm mainly migrated into granules of 1-3 mm;fuel particles with size of 1-3,3-5 and 5-8 mm mainly entered the granules with the same grain size.With the increase in fuel particles grain size from-0.5 to+8 mm,the combustion efficiency exhibited a firstly-increasing and then decreasing tendency,while the NO_(x) exhibited a decreasing tendency.Potential reason can be described that finer fuel particles(-1 mm)easily distributed in the outer layer of the granules,which combusted fiercely due to its larger specific surface area,leading to the development of incomplete combustion and the conversion of fuel nitrogen;the combustion efficiency of larger fuel particles was restricted by the inner diffusion of O_(2),which then contributed to the reduction of NO_(x) under the inadequate combustion atmosphere. 展开更多
关键词 Iron ore sintering GRANULATION Solid fuel distribution Pollutant emission Combustion efficiency
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Dynamically Tunable Perfect Absorbers Utilizing Hexagonal Aluminum Nano-Disk Array Cooperated with Vanadium Dioxide
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作者 Peng Zhou gai-ge Zheng +2 位作者 Yun-Yun Chen Feng-Lin Xian Lin-Hua xu 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第1期19-23,共5页
A tunable perfect absorber composed of hexagonal-arranged aluminum nano-disk array embedded in the vanadium dioxide(VO_2) film is proposed. The aim is to achieve the tunability of resonance absorption peak in the visi... A tunable perfect absorber composed of hexagonal-arranged aluminum nano-disk array embedded in the vanadium dioxide(VO_2) film is proposed. The aim is to achieve the tunability of resonance absorption peak in the visible and near-infrared regimes. Numerical results reveal that the absorption peak achieves a large tunability of 76.6% while VO_2 undergoes a structural transition from insulator phase to metallic phase. By optimizing the structural parameters, an average absorption of 95% is achieved from 1242 to 1815 nm at the metallic phase state. In addition, the near unity absorption can be fulfilled in a wide range of incident angle(0°–60°) and under all polarization conditions. The method and results presented here would be beneficial for the design of active optoelectronic devices. 展开更多
关键词 VANADIUM Dioxide HEXAGONAL ALUMINUM nanodisc array ABSORBENT
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艾叶及其燃烧产物有效成分的研究进展 被引量:41
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作者 郑婷婷 田瑞昌 +4 位作者 刘国辉 刘全军 司清林 郝浩浩 孙改格 《中华中医药杂志》 CAS CSCD 北大核心 2019年第1期241-244,共4页
艾叶在临床上主要用于艾灸,具有镇痛、抗炎、止血、抗菌、抗病毒等多种生物活性,其中所含的挥发油和黄酮类成分是其发挥作用的主要活性成分,文章总结了不同产地、采收期、提取方法等因素对艾叶有效成分影响的研究现状,并对艾叶燃烧产物... 艾叶在临床上主要用于艾灸,具有镇痛、抗炎、止血、抗菌、抗病毒等多种生物活性,其中所含的挥发油和黄酮类成分是其发挥作用的主要活性成分,文章总结了不同产地、采收期、提取方法等因素对艾叶有效成分影响的研究现状,并对艾叶燃烧产物的化学成分、生物活性、安全性的研究进展进行归纳,旨在为艾叶的深入研究和开发利用提供依据和思路。 展开更多
关键词 艾叶 燃烧产物 生物活性 有效成分
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差分进化帝王蝶优化算法求解折扣{0-1}背包问题 被引量:21
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作者 冯艳红 杨娟 +1 位作者 贺毅朝 王改革 《电子学报》 EI CAS CSCD 北大核心 2018年第6期1343-1350,共8页
帝王蝶优化算法(Monarch Butterfly Optimization,MBO)是一种新颖的群体智能算法,自从提出就在实际优化问题上表现出很好的性能.但是,帝王蝶优化算法的迁移算子采用随机选择两个个体来生成新个体,并没有记忆整个种群的最优解,容易造成... 帝王蝶优化算法(Monarch Butterfly Optimization,MBO)是一种新颖的群体智能算法,自从提出就在实际优化问题上表现出很好的性能.但是,帝王蝶优化算法的迁移算子采用随机选择两个个体来生成新个体,并没有记忆整个种群的最优解,容易造成全局最优帝王蝶搜索经验的丢失.根据MBO寻优过程的内在机制以及差分进化算法的变异算子能够利用个体间的差异信息,将MBO分别与目前性能最优、应用范围最广的7种差分进化(Differential Evolution,DE)变异策略相结合,实验验证了7种不同算法的性能.基于性能最优的DE/best/2/bin变异模式,提出了一种差分进化帝王蝶优化算法(Monarch Butterfly Optimization Algorithm with Differential Evolution,DEMBO),使得算法能够记忆种群最优解并实现种群内部信息的充分共享,达到既加快收敛速度又提高解的精度的目的.在30个典型折扣{0-1}背包问题(D{0-1}KP)实例上进行了一系列实验,实验结果表明:(1)DEMBO能够在时间复杂度不变的条件下,显著提高算法的求解精度和收敛速度;(2)DEMBO在求解所有D{0-1}KP实例时,均能够获得一个近似比非常接近1的近似解. 展开更多
关键词 折扣{0-1}背包问题 差分进化 帝王蝶优化算法 贪心修复策略 近似比
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节能型换热设备与流程的一体化创新 被引量:20
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作者 陈永东 程沛 +2 位作者 于改革 吴晓红 闫永超 《流体机械》 CSCD 北大核心 2018年第10期15-21,共7页
针对重点换热设备在流程工业中扮演着重要的角色,指出了其在流程工业中表现出的2个方面的作用,并阐述了设备与流程的一体化节能创新的实质,明确了设备与工艺流程的关系。着重介绍了2种高压高效节能换热器即炼油领域缠绕管式换热器和印... 针对重点换热设备在流程工业中扮演着重要的角色,指出了其在流程工业中表现出的2个方面的作用,并阐述了设备与流程的一体化节能创新的实质,明确了设备与工艺流程的关系。着重介绍了2种高压高效节能换热器即炼油领域缠绕管式换热器和印刷电路板式换热器的基本结构。基于缠绕管式换热器,介绍了节能型加氢裂化/加氢改质工艺中设备与流程的一体化创新;基于印刷电路板式换热器,介绍了天然气液化工厂混合冷剂冷却工艺的改进。列举了Hammerfest液化工厂混合冷剂海水换热器的失效案例,强调了安全性与能效性协同的重要性。简介了3种结构形式海水混合冷剂换热器比例样机的试验研究结果,介绍了我国研制混合冷剂海水换热器过程中,力求寻找一种安全和能效的平衡。最后指出,仅考虑换热设备的安全性或者能效性都是不够的,要从换热设备和流程工艺之间的相互关系和相互作用出发,在系统的层面上考虑基于能效和本质安全和谐统一的完整性,实现换热设备和流程的一体化节能创新。 展开更多
关键词 换热设备 流程工艺 节能 一体化 创新
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印刷电路板式换热器Zigzag通道流动与传热数值模拟 被引量:17
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作者 李雪 陈永东 +1 位作者 于改革 吴晓红 《流体机械》 CSCD 北大核心 2017年第11期72-78,共7页
印刷电路板式换热器以其高效、紧凑、耐高温、耐高压等特点,在核能、太阳能、液化天然气等清洁能源领域具有广阔的发展潜力。本文通过建立三维传热数值模型,研究了印刷电路板式换热器Zigzag通道内部冷、热流体的流动与传热基本规律,并... 印刷电路板式换热器以其高效、紧凑、耐高温、耐高压等特点,在核能、太阳能、液化天然气等清洁能源领域具有广阔的发展潜力。本文通过建立三维传热数值模型,研究了印刷电路板式换热器Zigzag通道内部冷、热流体的流动与传热基本规律,并与试验结果进行对比,验证了模型的准确性;分析了Zigzag通道角度对流体流速、温度分布的影响规律,并以(Nu/Nu0)/(f/f0)作为评价指标,对通道角度与流动条件进行耦合优化。研究表明:当Re≥250时,15°、25°的Zigzag通道综合性能优越,且15°的Zigzag通道性能最佳;而30°、45°的Zigzag通道综合性能不理想,尤其是45°的Zigzag通道,其综合性能始终低于直通道。研究结果可为印刷电路板式换热器的热力设计提供重要参考。 展开更多
关键词 PCHE Zigzag通道 通道角度 流固耦合传热 综合性能
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依托咪酯联合丙泊酚镇静应用于超重患者无痛胃镜检查的效果观察 被引量:16
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作者 周雁楠 方卫萍 +3 位作者 沈启英 汪欢 孟改革 郑伟健 《中国中西医结合消化杂志》 CAS 2020年第4期256-259,共4页
[目的]比较超重患者无痛胃镜检查中依托咪酯联合丙泊酚与单独使用丙泊酚的效果。[方法]将60例患者随机分为丙泊酚组(P组)和依托咪酯联合丙泊酚组(EP组)。P组在胃镜检查前首次给予1%丙泊酚(1 mg/kg),EP组给予1%丙泊酚(0.5 mg/kg)加依托咪... [目的]比较超重患者无痛胃镜检查中依托咪酯联合丙泊酚与单独使用丙泊酚的效果。[方法]将60例患者随机分为丙泊酚组(P组)和依托咪酯联合丙泊酚组(EP组)。P组在胃镜检查前首次给予1%丙泊酚(1 mg/kg),EP组给予1%丙泊酚(0.5 mg/kg)加依托咪酯(0.1 mg/kg)。后重复给予P组10~20 mg丙泊酚或EP组5~10 mg丙泊酚加1~2 mg依托咪酯,以维持足够的镇静水平。[结果]与T0比较,T1及T2时刻2组患者的收缩压、舒张压、平均动脉压、心率均明显降低,且与EP组相比,P组下降更为显著,差异有统计学意义(P<0.05),EP组麻醉后循环波动较小。与P组相比,EP组患者从静脉注入麻醉药物到患者意识消失的时间更长(P<0.05)。EP组低血压、呼吸抑制以及注射痛的发生例数低于P组,差异有统计学意义(均P<0.05)。[结论]依托咪酯联合丙泊酚对超重患者无痛胃镜检查中的呼吸和循环影响不大,患者苏醒质量高,不良反应少,比单用丙泊酚更安全有效。 展开更多
关键词 超重 无痛胃镜 丙泊酚 依托咪酯
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利用多重PCR技术快速检测五个转基因大豆品系 被引量:16
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作者 董立明 李葱葱 +4 位作者 邢珍娟 邵改革 夏蔚 闫伟 李飞武 《大豆科学》 CAS CSCD 北大核心 2016年第6期1002-1007,共6页
转基因大豆305423、MON89788、CV127、GTS40-3-2、356043作为商品化应用最为广泛的大豆品系,种植面积占世界转基因大豆总种植面积的80%以上。根据大豆内标准基因Lectin和5种转基因大豆品系的边界序列设计特异性引物。通过验证引物的适... 转基因大豆305423、MON89788、CV127、GTS40-3-2、356043作为商品化应用最为广泛的大豆品系,种植面积占世界转基因大豆总种植面积的80%以上。根据大豆内标准基因Lectin和5种转基因大豆品系的边界序列设计特异性引物。通过验证引物的适用性、特异性和灵敏度,优化多重PCR检测体系中不同引物的用量及反应退火温度,建立了能同时扩增大豆内源基因Lectin和5个转基因大豆品系的六重PCR检测体系。结果表明:确定的大豆内源基因和5个转基因大豆品系的引物具有很好的特异性,引物之间无交叉扩增和非特异性扩增,多重PCR方法的检测灵敏度达到0.1%。该方法可作为转基因大豆及其产品成分检测的辅助手段,快速检测转基因大豆及其产品中的相应品系。 展开更多
关键词 转基因大豆 多重PCR 品系特异性检测
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印刷电路板式换热器板片结构强度设计 被引量:14
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作者 于改革 姚志燕 +2 位作者 陈永东 吴晓红 刘孝根 《压力容器》 北大核心 2018年第12期42-46,33,共6页
针对印刷电路板式换热器芯体板片结构在内压作用下的应力分布情况,采用有限元法研究了关键位置的应力随板片结构参数的变化规律;对比分析了印刷电路板式换热器芯体板片结构采用有限元法和解析法的计算结果,指出了目前解析法进行结构应... 针对印刷电路板式换热器芯体板片结构在内压作用下的应力分布情况,采用有限元法研究了关键位置的应力随板片结构参数的变化规律;对比分析了印刷电路板式换热器芯体板片结构采用有限元法和解析法的计算结果,指出了目前解析法进行结构应力分析时考虑不够充分,且部分应力的计算结果存在较大的偏差。建议在进行印刷电路板式换热器芯体板片工程设计时,先利用现有解析法获得板片的初步厚度和肋宽,再用有限元法进行详细的校核和优化。 展开更多
关键词 印刷电路板式换热器 应力 有限元 设计
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不同降雨年份控释尿素与普通尿素配施对夏玉米产量、氮素利用及经济效益的影响 被引量:13
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作者 任宁 汪洋 +4 位作者 王改革 赵亚南 黄玉芳 岳松华 叶优良 《植物营养与肥料学报》 CAS CSCD 北大核心 2020年第4期681-691,共11页
【目的】在干旱和正常降雨年份,比较控释尿素与普通尿素不同配施比例对玉米产量和经济效益的影响,为夏玉米养分科学管理提供依据。【方法】试验于2017—2018年在河南省禹州市顺店镇进行,该地2017年6—9月降雨量为210.9 mm,属少雨干旱年... 【目的】在干旱和正常降雨年份,比较控释尿素与普通尿素不同配施比例对玉米产量和经济效益的影响,为夏玉米养分科学管理提供依据。【方法】试验于2017—2018年在河南省禹州市顺店镇进行,该地2017年6—9月降雨量为210.9 mm,属少雨干旱年份;2018年6—9月,降雨量为533.9 mm,属降雨正常年份。试验设置控释尿素(N 45%)与普通尿素(N 46%)的配比分别为1∶9、2∶8、3∶7、4∶6、5∶5,施氮量均为N180 kg/hm^2。于拔节期、大喇叭口期、开花期、乳熟期、成熟期取植株样品,测定植株全氮含量;于成熟期,测定玉米产量同时测试土壤无机氮含量。【结果】不同降雨年份玉米产量差异显著,相同处理下干旱年份(2017)与降雨正常年份(2018)相比玉米减产36.5%~53.4%。在降雨正常年份,与仅施普通尿素相比,控释尿素与普通尿素以4:6配比的玉米产量提高10.1%,经济效益提高15.8%。在干旱年份,与仅施普通尿素处理相比,控释尿素与普通尿素配施处理的玉米产量有所下降,其中CRU4显著减产22.9%,经济效益降低56.7%,当控释尿素与普通尿素比例为4∶6时减产幅度达到最大,经济效益也最低。相同配施处理下,在降雨正常年份玉米花后氮素累积比干旱年份增长108.0%~1175.7%,氮肥偏生产力增长57.4%~114.6%。在干旱年份,控释尿素与普通尿素配施处理的表层土壤硝态氮含量比降雨正常年份高52.3%~131.9%。在降雨正常年份,控释尿素与普通尿素配施处理土壤表层(0—30 cm)硝态氮含量均高于仅施普通尿素的处理。【结论】与正常降雨年份相比,干旱可导致玉米减产36.5%~53.4%,植株干物质累积量、氮素累积量、氮肥偏生产力均有所降低,土壤硝态氮残留量升高52.3%~131.9%。正常降雨量下,控释尿素与普通尿素配施能够提高玉米氮素累积量和经济效益,控释尿素与普通尿素在3∶7的配比下能获得最佳经济效益。 展开更多
关键词 降雨量 控释尿素 玉米产量 氮素利用 经济效益
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河北省2013~2020年大气污染治理进程中的减污降碳协同效益 被引量:7
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作者 孙世达 张改革 +8 位作者 孙露娜 徐晨曦 郭梦婕 崔泽琪 何学娟 李富柏 宋子谦 薄宇 贺克斌 《环境科学》 EI CAS CSCD 北大核心 2023年第10期5431-5442,共12页
当前,我国面临着大气污染治理与碳减排的双重挑战,"减污降碳"成为了社会经济绿色转型的重要抓手.大气污染物和CO_(2)排放清单是"减污降碳"工作的基础支撑,但已有研究存在着物种覆盖不全、源类体系不一、时间范围较... 当前,我国面临着大气污染治理与碳减排的双重挑战,"减污降碳"成为了社会经济绿色转型的重要抓手.大气污染物和CO_(2)排放清单是"减污降碳"工作的基础支撑,但已有研究存在着物种覆盖不全、源类体系不一、时间范围较窄等问题.基于统一的源分类体系与源排放表征技术,建立了河北省2013~2020年排放清单,据此分析了排放的总量趋势、结构演变、变化驱动、协同效益和区域分布.研究期内,河北省取得了社会经济发展与人为源排放控制的双赢,SO_(2)排放在"大气十条"期间下降速度较快,VOCs和NH_(3)排放在"蓝天保卫战"期间减排效果更好,NO_(x)和PM_(2.5)排放的下降速度相对稳定,CO_(2)排放略有上升.燃煤治理有效削减了大气污染物和CO_(2)排放,重点行业超低排放改造降低了SO_(2)、NO_(x)和PM_(2.5)排放,但VOCs治理力度有待提升.电力源和民用源实现了大气污染物与CO_(2)的协同减排,散煤治理从源头优化了能源结构,使得民用源具有更高的减排协同度.河北省"减污降碳"的重点区域为石家庄、唐山、邯郸、保定和廊坊.研究提出的方法与结论可为区域"减污降碳"工作提供技术借鉴与决策参考. 展开更多
关键词 排放清单 大气污染物 碳排放 协同效益 河北省
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