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Experimental investigation of surface roughness effects on flow behavior and heat transfer characteristics for circular microchannels

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Chinese Journal of Aeronautics 2016年第6期29卷 1575-1581页

作者： Yuan xing Tao zhi Li Haiwang Tian Yitu National Key Laboratory of Science and Technology on Aero-Engine Beihang University Collaborative Innovation Center for Advanced Aero-Engine of China of Aerodynamics Beihang University

This paper experimentally investigates the effect of surface roughness on flow and heat transfer characteristics in circular microchannels. All test pieces include 44 identical, parallel circular microchannels with diameters of 0.4 mm and 10 mm in length. The surface roughness of the microchannels is R= 0.86, 0.92, 1.02 lm, and the Reynolds number ranges from 150 to *** show that the surface roughness of the circular microchannels has remarkable effects on the performance of flow behavior and heat transfer. It is found that the Poiseuille and Nusselt numbers are higher when the relative surface roughness is larger. For flow behavior, the friction factor increases consistently with the increasing Reynolds number, and it is larger than the constant theoretical value for macrochannels. The Reynolds number for the transition from laminar to turbulent flow is about 1500, which is lower than the value for macrochannels. For the heat transfer property, Nusselt number also increases with increasing Reynolds number, and larger roughness contributes to higher Nusselt number.

关键词： Circular Flow behavior Heat transfer Microchannels Roughness

Using shapes correlation for active contour segmentation of uterine fibroid ultrasound images in computer-aided therapy

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Applied Mathematics(A Journal of Chinese Universities) 2016年第1期31卷 37-52页

作者： ni Bo HE Fa-zhi PAN Yi-teng YUAN zhi-yong School of Computer Science Wuhan University School of Computer Science Hubei Polytechnic University

Segmenting the lesion regions from the ultrasound （US） images is an important step in the intra-operative planning of some computer-aided therapies. High-Intensity Focused Ultrasound （HIFU）, as a popular computer-aided therapy, has been widely used in the treatment of uterine fibroids. However, such segmentation in HIFU remains challenge for two reasons：（1） the blurry or missing boundaries of lesion regions in the HIFU images and （2） the deformation of uterine fibroids caused by the patient＇s breathing or an external force during the US imaging process, which can lead to complex shapes of lesion regions. These factors have prevented classical active contour-based segmentation methods from yielding desired results for uterine fibroids in US images. In this paper, a novel active contour-based segmentation method is proposed, which utilizes the correlation information of target shapes among a sequence of images as prior knowledge to aid the existing active contour method. This prior knowledge can be interpreted as a unsupervised clustering of shapes prior modeling. Meanwhile, it is also proved that the shapes correlation has the low-rank property in a linear space, and the theory of matrix recovery is used as an effective tool to impose the proposed prior on an existing active contour model. Finally, an accurate method is developed to solve the proposed model by using the Augmented Lagrange Multiplier （ALM）. Experimental results from both synthetic and clinical uterine fibroids US image sequences demonstrate that the proposed method can consistently improve the performance of active contour models and increase the robustness against missing or misleading boundaries, and can greatly improve the efficiency of HIFU therapy.

关键词： Active contour shapes correlation ultrasound image segmentation matrix recovery computer-aided therapy.

Amino Acids Functionalized Graphene Oxide for Enhanced Hydrophilicity and Antifouling Property of Poly(vinylidene fluoride) Membranes

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Chinese Journal of Polymer Science 2016年第7期34卷 805-819页

作者：李建华 shuang-shuang wang de-bin zhang xing-xing ni 张其清 Institute of Biomedical and Pharmaeeutical Teehnology Fuzhou University Fuzhou 350001 China

Herein, functionalized graphene oxide（GO） was prepared by the covalent functionalization with amino acids（lysine, glycine, glutamic acid and tyrosine） in this study. Zeta potential results demonstrated that covalent functionalization of GO with amino acids was favourable for their homogeneous dispersion in water and organic solvents. Based on the higher absolute value of zeta potential and the better dipersion stability of GO-lysine, the PVDF/GO-lysine hybrid membranes were then prepared via the phase inversion induced by immersion precipitation technique. SEM images showed a better pore diameter and porosity distribution on the PVDF/GO-lysine membrane surface. The zeta potential absolute value of the PVDF/GO-lysine membrane surface was higher than that of the virgin PVDF membrane. Furthermore, the PVDF/GO-lysine membranes surface exhibited good hydrophilicity. The water flux of PVDF/GO-lysine membranes can reach two times of that of the virgin PVDF membrane. And the BSA adsorbed amount on PVDF/GO-lysine surface was decreased to 0.82 mg/cm^2 for PVDF/GO-lysine-8% membrane. Filtration experiment results indicated that the fouling resistance was significantly improved for the PVDF/GO-lysine membranes. As a result, lysine functionalized GO will provide a promising method to fabricate graphene oxide based hybrid membranes with effective antifouling property and hydrophilicity.

关键词： PVDF membrane Graphene oxide Amino acids Hydrophilicity Antifouling property

Quantum State Transfer for Two Atoms with a Single Resonant Interaction

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Communications in Theoretical Physics 2007年第5X期48卷 831-833页

作者： WU Tao ni zhi-Xiang YE Liu Department of Physics Fuyang Teachers College Fuyang 236041 China School of Physics & Material Science Anhui University Hefei 230039 China

We present a scheme for transferring an unknown atomic entangled state with a single resonant interaction. This scheme only requires a single resonant interaction of two atoms with a cavity mode and does not use the cavity mode as the memory. Thus the scheme is very simple and the interaction time is very short, which is important, in view of decoherence. Quantum state can be directly transferred from two atoms to another two at, oms with a successful probability of 100 percent.

关键词： transfer cavity QED resonant interaction quantum entanglement

Cryopreservation of Queen Honeybee (Apis mellifera carnica) Born Worker Eggs by Vitrification

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Agricultural Sciences in China 2010年第9期9卷 1353-1361页

作者： LI zhi-yong XUE Yun-bo WANG zhi LI xing-an Key Laboratory for Honeybee Genetics and Breeding Jilin Provincial Apiculture Institute Jilin 132108 P.R. China

Many species of insect egg can be targeted individually or （and） collectively for cryopreservation by vitrification. However, there has been no report on cryopreservation of honeybee eggs by vitrification. In an attempt to define a preliminary procedure of cryopreservation of honeybee eggs by vitrification, queen honeybee born worker eggs （worker eggs） were stored through vitrification in liquid nitrogen up to 1 h, and then post-vitrification survival of the vitrified worker eggs in vitro and their hatching rates during maturation in vivo were observed using microscopic and close visual inspections. The procedure of cryopreservation by vitrification included dechorionation with sodium hypochlorite and permeabilization with isopropyl alcohol; equilibration by addition of loading solution （i.e., 25% vitrification storage solution） and dehydration by gradual replacement of loading solution with vitrification storage solution; cooling in liquid nitrogen vapor right before droplet vitrification in liquid nitrogen; and recovery in liquid nitrogen vapor right after storage in liquid nitrogen, thawing at temperature of thawing medium （5% sucrose in TC 100-insect medium） and rehydration by gradual replacement of vitrification storage solution with rehydration solution （5% fetal bovine serum in TC 100-insect medium）. It was found that among the worker eggs experiencing cyropreservation by vitrification, 1.25% of them were successfully passed through the four life stages, viz., egg, larva, pupa, and adult. In summary, it can be inferred that although a majority of worker eggs were dead after cyropreservation by vitrification, a few of them were developed into larvae, pupae, and finally emerged as adults.

关键词： honeybee worker egg cryopreservation vitrification

Sorafenib Combined with Cryoablation to Treat Unresectable Hepatocellular Carcinoma

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Chinese Journal of Cancer Research 2011年第3期23卷 188-193页

作者： Hong ni Mao Yang zhi Guo Ti Zhang Department of Interventional Therapy Tianjin 300060China Department of Hepatobiliary Disease Cancer Institute ＆ HospitalTianjin Medical UniversityTianjin 300060China

Objective：To evaluate the efficacy and tolerability of sorafenib combined with cryoablation in treating unresectable hepatocellular carcinoma （HCC）.Methods：Patients with unresectable advanced HCC received cryoablation and sorafenib at a dose of 400 mg twice daily in 4-week cycles on the same day of the *** response,median overall survival and the median time to radiological progression were calculated and the toxicity was ***：Seventy-eight patients with unresectable HCC were involved in this *** median age was 52 years （range,22-81 years）.The Eastern Cooperative Oncology Group （ECOG） performance status scores were 0 （39.7%）,1 （55.1%）,and 2 （5.1%）.nine （11.5%） patients were at Barcelona clinic liver cancer （BCLC） stage A,twenty-four （30.8%） patients were at stage B and 45 （57.7%） patients were at stage *** （6.4%） achieved partial responses,and 34 （43.6%） achieved stable *** median time to progression （TTP） for all enrolled patients was 6.6 months and the median overall survival （OS） was 12.2 ***：Cryoablation combined with sorafenib demonstrates good efficacy and acceptable tolerability in treating unresectable advanced HCC patients.

关键词： Hepatocellular carcinoma Sorafenib Cryoablation Unresectable

Novel Stereoselective Carbonyl Reductase from Kluyveromyces marxianus for Chiral Alcohols Synthesis

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Chemical Research in Chinese Universities 2013年第6期29卷 1140-1148页

作者： LI Hai-dong SUN zhi-hao ni Ye Key Laboratory of Industrial Biotechnology Ministry of Education School of BiotechnologyJiangnan University Wuxi 214122 P.R.China

A novel nicotinamide adenine dinucleotide phosphate（NADPH）-dependent carbonyl reductase from Kluyverornyces marxianus（KmCR） was identified, which can convert various prochiral ketone esters and ketone substrates to their corresponding chiral alcohols. KmCR was over-expressed in E. coli BL21（DE3）, purified to homogeneity, and characterized. The purified enzyme exhibits the highest activity at 40℃ and pH=6.0. Based on the gel filtration and sodium dodecyl sulfate-polyacrylamide gel eiectrophoresis（SDS-PAGE） analysis, the monomeric protein was determined to have a molecular weight of approximate 39000. Vmax and Km of KmCR are 4.28 μ***^-1·mg^-1 and 0.41 mmol/L for ketone ester substrate ethyl 2-oxo-4-phenylbutyrate（OPBE）, 3.09μ***^-1·mg^-1 and 1.21 mmol/L for cofactor NADPH, respectively. Cofactor recycle was achieved by co-expression of KmCR and glucose dehydrogenase（GDH） in E. coli. Recombinant E. coli harboring KmCR and GDH showed moderate asymmetric reduction activity towards various α- and β-ketoesters, diaryl ketone substrates. In an aqueous/butyl acetate biphasic system, the whole-cell biocatalyst was used to prepare ethyl （R）-2-hydroxy-4- phenylbutanoate[（R）-HPBE] in an e.e. of 99.5% with a space-time yield of 433.6 g.L-1.d-1 and a yield of 80.3% at 270 g/L OPBE.

关键词： Carbonyl reductase Asymmetric reduction Chiral alcohol co-Expression Kluyveromyces marxianus

Synthesis and Biological Activities of 3-(2-Furyl)-4-aryl-1, 2, 4-triazole-5-thiones

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Chinese Chemical Letters 2002年第2期13卷 129-132页

作者： Xin zhi LI Zong xing SI Department of Applied Chemistry China Agricultural UniversityBeijing 100094

A series of novel compounds 3-(2-furyl)-4-aryl-1, 2, 4-triazole-5-thiones have been synthesized. All the compounds were characterized by spectral data and elemental analysis. The preliminary biological test showed t... 详细信息

关键词： Triazoles synthesis biological activities.

Transferring of a Two-Mode Entangled State Between Two Cavities via Cavity QED

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Communications in Theoretical Physics 2007年第3期47卷 451-453页

作者： WU Tao ni zhi-Xiang YE Liu School of Physics ＆ Material Science Anhui University Hefei 230039 China Department of Physics Fuyang Teachers College Fuyang 236032 China

We propose a scheme for transferring of a two-mode entanglement of zero- or one-photon entangled states between two cavities via atom-cavity field resonant interaction. In our proposal, in order to transfer the entangled state, we only need two identical two-level atoms and a two-mode cavity for receiving the teleported state. This scheme does not require Bell-state measurement and performing any transformations to reconstruct the initial state. And the transfer can occur with 100% success probability in a simple manner. And a network for transferring of a two-mode entangled state between cavities is suggested. This scheme can also be extended to transfer N-mode entangled state of cavity.

关键词： transfer cavity QED quantum entanglement resonant interaction