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Experimental research on the heating performance of a single cylinder refrigerant injection rotary compressor heat pump with flash tank

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Science China(Technological Sciences) 2018年第12期61卷 1814-1823页

作者： SUN JinFei zhu DongSheng yin yingDe LI XiuZhen Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Guangzhou 510640 China Key Laboratory of Renewable Energy Chinese Academy of Sciences Guangzhou 510640 China Guangdong Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640 China University of Chinese Academy of Sciences Beijing 100049 China

A single cylinder rotary compressor was applied in the refrigerant injection air-source heat pump to improve the heating performance in cold regions. In this study, the performance of an R410 A single cylinder rotary compressor vapor injection(SCRCVI) system was measured and analyzed by varying the compressor frequency f and injection pressure Pi njat the ambient temperature To d=–10°*** experimental results indicated that an optimum injection pressure to gain the maximum COP_h (coefficient of performance) existed in the SCRCVI cycle. However, the maximum COP_h of the SCRCVI system decreased as the increase of the frequency, and the maximum COPhwas even lower than that of the CSVC system at high compressor frequency. Therefore, in view of the energy saving and emission reduction, the SCRCVI system should be switched to single stage compression system when the heating capacity demand could be satisfied at high compressor frequency f. Compared to the conventional single-stage vapor compression(CSVC) system, refrigerant injection could enhance the heating capacities and COP_h by 28.2% and 7.91%, respectively. The average total mass flow rate of the SCRCVI system was 24.68% higher than that of the CSVC system. As the SCRCVI system worked at the optimum injection pressure, the variation trends of the different system parameters were investigated in detail. These trends were reliably used to optimize the refrigerant injection system design and the control strategy. The parameter of(P_(inj)–P_s) could be adopted as the signals to control the opening of the upper stage electronic expansion valve EEV1.

关键词： rotary compressor refrigerant injection DC (direct current) inverter heat pump heating performance injection pressure

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Asymmetric Hydrogenation Synthesis of (S)-(+)-2-(6′-methoxyl-2-naphthyl) propionic Acid by Cinchona Modified Pd(0)-α-FeOOH Catalyst

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Chinese Chemical Letters 2003年第11期14卷 1101-1104页

作者： Hong zhu MA bo WANG College of Chemistry and materials science ShaanXi Normal UniversityXian 710062

Asymmetric hydrogenation of (6-methoxyl-2-naphthyl)-2-acrylic acid catalyzed by cinchona modified Pd(0)-a-FeOOH was reported and ee抯 of (S)-(+)-2-(6′-methoxyl-2-naphthyl) propionic acid ((S)-(+)-naproxen) up to 98% ... 详细信息

关键词： Asymmetric hydrogenation catalyze cinchona Pd(0)-a-FeOOH (S)-(+)-naproxen.

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Beam scan mode analysis and design for geosynchronous SAR

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Science China(Information Sciences) 2017年第6期60卷 72-84页

作者： Wei yin Zegang DING Xiaojun LU Yu zhu Beijing Key Laboratory of Embedded Real-time Information Processing Technology School of Information and Electronics Beijing Institute of Technology Beijing Institute of Spacecraft System Engineering Chinese Academy of Space Technology

The beam velocity of geosynchronous synthetic aperture radar(GEO SAR) varies seriously with the orbital position and the scene position, which leads to a significant variation of the scene length and the azimuth resolution in the stripmap(SM) mode. To obtain uniform scene length and azimuth resolution, beam scan modes can be utilized in GEO SAR, such as the sliding spotlight(SLL) mode and the terrain observation by progressive scans(TOPS) mode. However, the conventional design method of the beam scan mode is based on the straight line model(SLM), which does not consider the effects of the curved satellite track and the spherical earth surface. To solve this problem, a curvature circle model(CCM) is proposed considering the actual satellite-earth relationship. By using the CCM, the beam velocity after the beam scan is derived. The scene length and the azimuth resolution are analyzed. The SLL mode and the TOPS mode are recommended for GEO SAR. After that, a design method of the beam scan mode is proposed based on the CMM. The performance of the proposed method is verified by computer simulations.

关键词： GEO SAR beam scan mode design azimuth resolution scene length

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Light-driven synthetic microbial consortia:playing with an oxygen dilemma

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Quantitative Biology 2023年第2期11卷 143-154页

作者： Huawei zhu yin Li CAs Key Laboratory of Microbial Physiological and Metabolic Engineering State Key Laboratory of Microbial ResourcesInstituteof MicrobiologyChineseAcademy of SciencesBeijing 100101China

Background:Light-driven synthetic microbial consortia are composed of photoautotrophs and *** exhibited better performance in stability,robustness and capacity for handling complex tasks when comparing with axenic *** from general microbial consortia,the intrinsic property of photosynthetic oxygen evolution in light-driven synthetic microbial consortia is an important factor affecting the functions of the ***:In light-driven microbial consortia,the oxygen liberated by photoautotrophs will result in an aerobic environment,which exerts dual effects on different species and *** one hand,oxygen is favorable to the synthetic microbial consortia when they are used for wastewater treatment and aerobic chemical production,in which biomass accumulation and oxidized product formation will benefit from the high energy yield of aerobic *** the other hand,the oxygen is harmful to the synthetic microbial consortia when they were used for anaerobic processes including biohydrogen production and bioelectricity generation,in which the presence of oxygen will deactivate some biological components and compete for ***:Developing anaerobic processes in using light-driven synthetic microbial consortia represents a costeffective alternative for production of chemicals from carbon dioxide and ***,exploring a versatile approach addressing the oxygen dilemma is essential to enable light-driven synthetic microbial consortia to get closer to practical applications.

关键词： synthetic microbial consortia oxygen dilemma photosynthesis

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Design of 3D-printed Cable Driven Humanoid Hand Based on Bidirectional Elastomeric Passive Transmission

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Chinese Journal of Mechanical Engineering 2021年第4期34卷 225-235页

作者： Teru Chen Xingwei Zhao Guocai Ma bo Tao Zhouping yin State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Intelligent Manufacturing System Technology Beijing Institute of Electronic System EngineeringBeijing 100854China

Motion control of the human hand is the most complex part of the human *** has always been a challenge for a good balance between the cost,weight,responding speed,grasping force,finger extension,and dexterity of prosthetic *** solve these issues,a 3D-printed cable driven humanoid hand based on bidirectional elastomeric passive transmission(BEPT)is designed in this paper.A semi-static model of BEPT is investigated based on energy conservation law to analyze the mechanical properties of BEPT and a dynamical simulation of finger grasping is *** a good imitation of human hand and an excellent grasping performance,specific BEPT is selected according to human finger grasping *** advantage of BEPT based humanoid hand is that a good balance between the price and performance of the humanoid hand is *** proved that the designed prosthetic hand’s single fingertip force can reach 33 N and the fastest fingertip grasping speed realized 0.6 s/180°.It also has a good force compliance effect with only 430g’s *** can not only grab fragile objects like raw eggs and paper cup,but also achieve strong grasping force to damage metal *** humanoid hand has considerable application prospects in artificial prosthesis,human-computer interaction,and robot operation.

关键词： Humanoid hand Bidirectional elastomeric passive transmission Artificial prosthesis

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A comparable study of clinical and optical outcomes after 1,8, 2,0 mm microcoaxial and 3,0 mm coaxial cataract surgery

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International Journal of Ophthalmology(English edition) 2016年第3期9卷 399-405页

作者： Yi-bo Yu Ya-Nan zhu Wei Wang Yi-Dong Zhang yin-Hui Yu Ke Yao Eye Center the Second Affiliated Hospital of Zhejiang University School of Medicine Hangzhou 310009 Zhejiang Province China Zhejiang Provincial Key Lab of Ophthalmology Hangzhou 310009 Zhejiang Province China

AIM： To evaluate the clinical pnd optical outcomes after clear corneal incision cataract surgery （ClCS） with three different incision sizes （1.8, 2.0 and 3.0 mm）. METHODS： Eyes of 150 patients with age-related cataract scheduled for coaxial cataract surgery were randomized to three groups： 1.8, 2.0, or 3.0 mm CICS. Intraoperative data and postoperative outcomes including surgically induced astigmatism （SIA）, the corneal incision thickness, wavefront aberrations and modulation transfer function （MTF） of cornea were obtained. RESULTS： There were no significant differences among the three groups in demographic characteristics and intraoperative outcome. The 1.8 and 2.0 mm microincisions showed more satisfactory clinical outcomes than the 3.0 mm incision. The 1.8 mm incision showed significantly less SIA than the 2.0 mm incision until postoperative lmo （P〈0.05）, but the difference was only 0.14-0.18 D. Combined with less increased incision thickness only at postoperative ld （P=0.013）, the 1.8 mm incision presented better uncorrected distance visual acuity （UCDVA） than the 2.0 mm incision only at Id postoperatively （P=0.008）. For higher-order aberrations and other Zernike coefficients, there were no significant differences between the 1.8 mm group and 2.0 mm group （P 〉0.05）. CONCLUSION： Converting from 3.0 mm CICS to 1.8 or 2.0 mm CICS result in better clinical and optical outcomes. However, when incision is 1.8 mm, the benefits from further reduction in size compared with2.0 mm are limited. The necessity to reduce the incision size is to be deliberated.

关键词： KEYWORDS: microsurgery, phacoemulsification treatmentoutcome

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Vibration Analysis of a Drillstring in Horizontal Well

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Computer Modeling in Engineering & Sciences 2019年第11期121卷 631-660页

作者： Xiaohua zhu Li Zeng bo Li School of Mechanical Engineering Southwest Petroleum University ChengduChengdu610500China

The complicated geological conditions will bring great challenges to the drillstring of horizontal wells for the reason that the increase of the well depth in Sichuan-Chongqing *** drillstring failure and friction during drilling are generally caused by drillstring vibration,great importance must be attached to computer simulation methods for the prediction of drillstring vibration.A finite element model considering axial,lateral and torsional vibration is *** order to verify the established numerical model,an indoor experimental device based on the similarity principle was *** vibration characteristics of three shale gas horizontal wells drillstrings are *** reasons for the large difference in vibration characteristics between the three wells were discussed by changing the well structure,BHA(bottom hole assembly)and drilling *** simulation results show that the depth of ultra-deep well 3 is only 1.27 times of that of medium-deep well 2,but the fluctuation of WOB(weight on bit)is 2.8 *** primary factor for the great difference of WOB fluctuation is the change of vertical section depth,the secondary factor is the change of the horizontal section ***,the reasonable range of speeds has been proposed and applied in the *** advantage of this numerical analysis method is that it can judge the vibration and friction torque of drillstring in horizontal wells with arbitrary structure,drilling parameters and *** method has certain guiding significance to the field practice.

关键词： Horizontal well drillstring vibration friction torque fatigue life

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Sampling adaptive block compressed sensing reconstruction algorithm for images based on edge detection

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The Journal of China Universities of Posts and Telecommunications 2013年第3期20卷 97-103页

作者： ZHENG Hai-bo zhu Xiu-chang School of Telecommunication and Information Engineering Nanjing University of Posts and Telecommunications

In this paper, a sampling adaptive for block compressed sensing with smooth projected Landweber based on edge detection （SA-BCS-SPL-ED） image reconstruction algorithm is presented. This algorithm takes full advantage of the characteristics of the block compressed sensing, which assigns a sampling rate depending on its texture complexity of each block. The block complexity is measured by the variance of its texture gradient, big variance with high sampling rates and small variance with low sampling rates. Meanwhile, in order to avoid over-sampling and sub-sampling, we set up the maximum sampling rate and the minimum sampling rate for each block. Through iterative algorithm, the actual sampling rate of the whole image approximately equals to the set up value. In aspects of the directional transforms, discrete cosine transform （DCT）, dual-tree discrete wavelet transform （DDWT）, discrete wavelet transform （DWT） and Contourlet （CT） are used in experiments. Experimental results show that compared to block compressed sensing with smooth projected Landweber （BCS-SPL）, the proposed algorithm is much better with simple texture images and even complicated texture images at the same sampling rate. Besides, SA-BCS-SPL-ED-DDWT is quite good for the most of images while the SA-BCS-SPL-ED-CT is likely better only for more-complicated texture images.

关键词： block compressed sensing edge detection sampling-adaptive variance directional transforms

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Effects of Contour Hedgerow Intercropping on Nutrient Losses from the Sloping Farmland in the Three Gorges Area,China

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Journal of Mountain Science 2012年第1期9卷 105-114页

作者： WANG Tao zhu bo XIA Lizhong Key Laboratory of Mountain Environment Evolvement and Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China Institute of Soil Science Chinese Academy of SciencesNanjing 210008China

Eutrophication is recognized as one of the major environmental problems in the Three Gorges *** hedgerows have been used as a major soil and water conservation measure in this ***,a two-year study was conducted to investigate the effects of contour hedgerow intercropping on nutrient loss from sloping farmland in this *** treatments were applied:(1) Maize + Soybean,(2) Maize,(3) Maize + Alfalfa,and(4) Maize + Hemerocallis citrina *** indicated that nutrient loss in the control treatment(Maize) was serious,especially the average loss flux of total nitrogen(2245.8 mg) and total phosphate(2434.2 mg) in a typical rainfall ***,the nutrient losses by runoff in the other three treatments with contour hedgerow intercropping showed significant *** with the control treatment,the total nitrogen loss in the Alfalfa and Hemerocallis citrina Baroni decreased by 80.9% and 85.0%,respectively,and the total phosphorus loss in the two treatments decreased by 91.2% and 92.5%,***,it is concluded that nutrient losses could be reduced by using contour hedgerows in the Three Gorges *** runoff volume and sediment loss was the main mechanisms of contour hedgerow intercropping to reduce nutrient loss.

关键词： Contour hedgerow Sloping farmland Nitrogen Phosphorus Three Gorges Reservoir China

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Unsaturated Creep Behaviors of Weak Intercalated Soils in Soft Rock of Badong Formation

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Journal of Mountain Science 2015年第6期12卷 1460-1470页

作者： zhu Yan-bo YU Hong-Ming College of Geology Engineering and Geomatics Chang'an University Faculty of Engineering China University of Geosciences

The cutting slopes in soft rock of redbed appeared in Yichang-Badong highway often suffer from the instability along weak intercalations, so the creep behaviors of weak intercalated soils are crucially important for the stability of cutting slopes. Because the deformation of weak intercalated soils is significantly affected by water content due to the strong water sensitivity, it is necessary to study the influence of matric suction on the creep behaviors of weak intercalated soils. In order to find out the unsaturated creep characters of weak intercalated soils, a GDS unsaturated triaxial apparatus was used. Then the triaxial creep experiments on weak intercalated soil samples under varying matric suction were conducted to obtain the unsaturated creep curves. The results show that the weak intercalated soils have obvious creep behaviors, and the creep strain is in nonlinear relationship with stress and time. When the matric suction is constant, a larger deviator stress will lead to a larger creep strain; When the deviator stress is constant, a smaller matric suction will lead to a larger creep strain. Based on the Mesri creep model, an improved creep model for weak intercalated soils under varying matric suction was established, in which the relationship of stress-strain was expressed with a hyperbolic function, and the relationship of strain-time was expressed with power functions in stages. Then an unsaturated creep model including stress-matric suction-strain-time for weak intercalated soils was established based on the power function relationship between matric suction and Ed(a parameter of the improved creep model). The comparison of the calculated values of creep model and the experimental values shows that the creep behaviors of weak intercalated soils can be predicted by the unsaturated creep model by and large.

关键词： Badong formation Weak intercalated soils Unsaturated creep behaviors Soil triaxial apparatus Creep model

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