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Optimal squeezed cooling of a mechanical oscillator using measurement-based vector feedback

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Science China(Physics,Mechanics & Astronomy) 2023年第7期66卷 55-61页

作者： zhi-Cheng Gong Cheng-Yu Shen Tian-Hua Mao Chang-Pu Sun yong Li hao Fu School of Science Hainan UniversityHaikou 570228China Innovation Academy for Precision Measurement Science and Technology Chinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100190China Graduate School of China Academy of Engineering Physics Beijing 100193China Beijing Computational Science Research Center Beijing 100193China Center for Theoretical Physics Hainan UniversityHaikou 570228China

Measurement-based feedback has been adopted as an efficient cooling scheme capable of suppressing the thermal fluctuation of a mechanical resonator to a level limited by measurement *** present a scheme of squeezed cooling in which the limit of feedback cooling imposed by the measurement imprecision is surpassed by parametrically squeezing the mechanical resonator in a periodically oscillating optical *** stabilize the parametrically amplified quadrature and simultaneously optimize the cooling for the squeezed quadrature,a measurement-based vector feedback capable of independently controlling the orthogonal motional quadrature is *** experiment demonstrates that the optimal condition for the squeezed cooling closely depends on the strength of *** the ability to keep the orthogonal quadrature well decoupled,optimal squeezed cooling of the mechanical resonator under strong squeezing is achieved with the squeezed variance becoming 8.1 dB below the limit of feedback cooling and the creation of a 31.7 dB thermomechanical squeezed *** this research is conducted in the classical regime,the scheme of squeezed cooling can be naturally extended to quantum systems with the prospects of creating quantum squeezing of a room-temperature mechanical resonator and enabling displacement measurement beyond the standard quantum limit.

关键词： squeezed cooling measurement-based feedback parametric squeezing optimal control optomechanics

Characteristics of timberline and treeline altitudinal distribution in *** and their geographical interpretation

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Journal of Mountain Science 2022年第10期19卷 2846-2860页

作者： MU hao-xiang HAN Fang ZHANG Bai-ping LIANG Tian WANG zhi-yong WANG Zhe School of Civil and Architectural Engineering Shandong University of TechnologyZibo 255000China State Key Lab for Resources and Environment Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Center for Yellow River Ecosystem Products Shandong UniversityQingdao 266237China

Different types of vegetation patches are alternately and randomly distributed in a timberline ecotone where the upper limit is the treeline and the lower limit is the ***,most studies on timberline/treeline altitudinal distributions have simplified timberline or treeline as continuous curves and disregarded the fuzziness of timberline/treeline and the randomness of different vegetation patch distributions in a timberline *** study the altitudinal distribution characteristics of timberline and treeline from the perspective of uncertainty theory,we constructed the timberline and treeline elevation cloud models in *** in east ***,we established multiple linear regression models by using nine influencing factors,namely,aspect,slope,topographic relief,dryness index,average temperature in January and July,latitude,summit syndrome(represented by the vertical distance from the peak),and snow effect(represented by the nearest distance from the snow)as independent variables,and the elevations of timberline/treeline as dependent *** we compared the contributions of the nine factors in timberline,treeline,and the core and peripheral areas of timberline and *** results show that 1)the timberline/treeline elevation cloud model can represent the overall characteristics(especially the uncertainty)of the altitudinal distributions of the timberline/treeline *** uncertainty of treeline’s altitudinal distribution is higher than that of timberline(entropy and hyper entropy:207.59 m and 70.36 m for treeline elevation cloud;entropy and hyper entropy:191.17 m and 50.13 m for timberline elevation cloud).2)The influence of climate and topography on timberline and treeline are *** average temperature in July has a significant negative correlation with the timberline/treeline elevation in ***,which is the most critical factor that affects timberline and treeline elevation,explaining the altitudinal

关键词： Timberline Treeline Geographical interpretation Uncertainty Influencing factors Mt.Namjagbarwa

G protein-coupled receptor kinase 2 inhibition improves erectile function through amelioration of endothelial dysfunction and oxidative stress in a rat model of type 2 diabetes

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Asian Journal of Andrology 2019年第1期21卷 74-79页

作者： zhi-Hua Wan Yuan-Jie Zhang Lin Chen yong-Lian Guo Guo-hao Li Ding Wu yong Wang Department of Urology The Central Hospital of WuhanTongll Medical CollegeHuazhong University of Science and TechnologyWuhan 430014China

Type 2 diabetes mellitus (T2DM)is a common cause of erectile dysfunction (ED).It has been demonstrated that G protein-coupled receptor kinase 2 (GRK2)overexpression contributes to diabetic endothelial dysfunction and oxidative stress,which also underlies ED in *** hypothesized that GRK2 overexpressed and attenuated endothelial function of the cavernosal tissue in a rat model of T2DM.T2DM rats were established by feeding with a high-fat diet (HFD)for 2 weeks and then administering two intraperitoneal (IP) injections of a low dose of streptozotocin (STZ),followed by continuous feeding with a HFD for 6 ***2 was inhibited by IP injection of paroxetine,a selective GRK2 inhibitor,after STZ *** challenge tests,intracavernous pressure (ICP), GRK2 expression,the protein kinase B (Akt)/endothelial nitric oxide synthase (eNOS)pathway,nicotinamide adenine dinucleotide phosphate (NADPH)oxidase subunit gp91phox,nitric oxide (NO),reactive oxygen species (ROS)production,and apoptosis in cavernosal tissue were *** response to insulin injection was observed in T2DM rats 2 weeks after *** increased GRK2 expression,along with impaired Akt/eNOS pathway,reduced NO production,increased gp91phox expression and ROS generation,increased apoptosis and impaired erectile function were found in T2DM *** of GRK2 with paroxetine ameliorated Akt/eNOS signaling,restored NO production,downregulated NADPH oxidase,subsequently inhibited ROS generation and apoptosis,and ultimately preserved erectile *** results indicated that GRK2 upregulation may be an important mechanism underlying T2DM ED,and GRK2 inhibition may be a potential therapeutic strategy for T2DM ED.

关键词： endothelial dysfunction erectile dysfunction G protein-coupled receptor kinase 2 oxidative stress type 2 diabetes mellitus

Relationships between gas reservoir and the evolution of stope surrounding rock fracture at the process of mining the closed distance protection layer

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Mining Science and Technology 2009年第5期19卷 653-656页

作者： hao zhi-yong LIN Bai-quan WU Hai-jin MENG Jie School of Safety Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Overburden rock movements and fracture developments occur during mining activities. Consequently, relief gas reservoirs and migration in coal seams being mined as well as in near distant coal seams appear. We considered a gas disaster management project and rules on stope relief of gas flows together and explored a gas reservoir and the evolution of stope surrounding rock fractures in the process of mining near distant protective layers by physical simulation, numerical simulation and field testing. Different techniques provide evidence of the rules of interaction of gas reservoirs and the evolution of surrounding rock fractures and are able to find accurately the gas-rich regions around the stope. Finally, we found that these rules can provide a basis for taking measures to prevent gas accidents in the protective layer of the coalface as well as for demonstrating and designing programs to drain high concentrations of gas from the gob.

关键词： physical simulation numerical simulation gas reservoir evolution of fractures

Overexpression of transglutaminase 4 and prostate cancer progression： a potential predictor of less favourable outcomes

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Asian Journal of Andrology 2013年第6期15卷 742-746,I0005,I0006页

作者： zhi Cao Yang Wang zhi-yong Liu Zhen-Sheng Zhang Shan-Cheng Ren yong-Wei Yu Meng Qiaol Bei-Bei Zhai Ying-hao Sun Department of Urology Changhai Hospital Second Military Medical University Shanghai 200433 China Department of Pathology Changhai Hospital Second Military Medical University Shanghai 200433 China

Transglutaminase 4 has been shown to enhance various biological properties of prostate cancer cells, e.g., cell-matrix adhesion, invasiveness and the epithelial-mesenchymal transition. The objectives of this study were to investigate the associations between transglutaminase 4 expression and the established features and biochemical recurrence of prostate cancer. Transglutaminase 4 immunostaining was performed on a tissue microarray. The expression of transglutaminase 4 was evaluated by a scoring method based on the intensity and extent of staining. The clinical and pathological information was obtained through a review of medical records. Follow-up data were obtained by consulting the hospital medical records and the prostate cancer database of our department and by contacting patients or family members. We then compared the transglutaminase 4 expression levels between the prostate cancer tissues and the paracarcinoma tissues and evaluated the correlation of transglutaminase 4 expression with the clinical parameters and biochemical recurrence of prostate cancer. Our results indicated that the transglutaminase 4 staining was significantly higher in tumour tissue than in paracarcinoma tissue （P^O.O01） and was positively associated with higher Gleason score （P^O.O01） and higher prostate-specific antigen level （P=0.005）. Patients with transglutaminase 4 overexpression experienced shorter biochemical recurrence-free survival after surgery （P=0.042） in the univariate analysis but not in the multivariate analysis （P=0. 139）, which indicated that transglutaminase 4 may serve as a potential predictor of biochemical recurrence of prostate cancer.

关键词： biochemical recurrence prostate cancer prostatectomy tissue microarray transglutaminase 4

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《电工技术》CAI课件的开发

天津职业大学学报 2004年第5期13卷 23-26页

作者：张金环康晓明宋志勇郝玉涛天津职业大学天津市300402

本文介绍了CAI课件在现代教学的必要性及作用,阐明了《电工技术》课件开发过程分为教学设计、脚本设计、课件制作、评价和修改等四个阶段。此课件现已应用于教学实践中,具有很好的实用性。

关键词：电工技术 CAI课件动画制作

Experimental Study of Air Layer Drag Reduction with Bottom Cavity for A Bulk Carrier Ship Model

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China Ocean Engineering 2019年第5期33卷 554-562页

作者： WU hao OU yong-peng Key Laboratory of High Performance Ship Technology (Wuhan University of Technology) Ministry of Education Wuhan 430063 China School of Transportation Wuhan University of Technology Wuhan 430063 China College of Naval Architecture and Ocean Engineering Naval University of Engineering Wuhan 430033 China

Air lubrication by means of a bottom cavity is a promising method for ship drag reduction. The characteristics of the bottom cavity are sensitive to the flow field around the ship hull and the effect of drag reduction, especially the depth of the bottom cavity. In this study, a ship model experiment of a bulk carrier is conducted in a towing tank using the method of air layer drag reduction (ALDR) with different bottom cavity depths. The shape of the air layer is observed, and the changes in resistance are measured. The model experiments produce results of approximately 20% for the total drag reduction at the ship design speed for a 25-mm cavity continuously supplied with air at Cq = 0.224 in calm water, and the air layer covers the whole cavity when the air flow rate is suitable. In a regular head wave, the air layer is easily broken and reduces the drag reduction rate in short waves, particularly when λ/Lw1 is close to one;however, it still has a good drag reduction effect in the long waves.

关键词： air layer drag reduction bulk carrier model test depth of cavity air layer shape

GC/MS Analysis of Fractional Extraction of Fusain from Tongting Bituminous Coal in CS_2

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Journal of China University of Mining and Technology 2006年第1期16卷 8-12页

作者： QIN zhi-hong JIANG Chun SUN hao ZONG zhi-min JIANG Bing WEI Xian-yong School of Chemical Engineering and Technology China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Fusain from Tongting (Huaibei, Anhui Province) bituminous (FTTB) coal was fractionally extracted using Soxhlet extractor with CS2. Then the extracts were analyzed with GC/MS. Comparison of experimental data between FTTB coal and clarain from Tongting bituminous (CTTB) coal was carried out. The results show that the kinds of small molecule components detected by GC/MS of FTTB are less than those of CTTB. Long-chain alkanes exist mostly in the extracts of fusain. Macromolecular networks are predominant in the FTTB coal mainly composed of inertinite in the coal petrography. The size of micropores in the FTTB coal is relatively small, and the development of micropores is relatively low. Thus the content of aromatic compounds with affinity for micropores is relative low in FTTB, while the content of long-chain alkanes with affinity for macromolecule networks is relatively high. Sub-components in exinite determine the distribution of long-chain alkanes extracted in the last stage. Odd-numbered carbon distribution appears when resin is most in exinite, while high carbon alkane distribution appears when exinite is dominant in cutinite. Small aromatic molecules are firstly packed in micropores, and exist in a free state after micropores are saturated.

关键词： coal fusain extraction fractional sample CS2 GC/MS

A simple and controllable nanostructure comprising non-conductive poly（vinylidene fluoride） and graphene nanosheets for supercapacitor

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Frontiers of Materials Science 2012年第2期6卷 149-159页

作者： Jing SUN Ling-hao HE Qiao-Ling Zhao Li-Fang CAI Rui SONG yong-Mei hao zhi MA WeiHUANG Key Lab of Surface and Interface Sciences of Henan Provincial Zhengzhou University of Light IndustryZhengzhou 450002China Shanghai Institute of Organic Chemistry Chinese Academy of SciencesShanghai 200032china College of Chemistry and Chemical Engineering Gracluate University of Chinese Academy of SciencesBeijing 100049China Laboratory of Advanced Polymer Materials Institute of Chemistry Chinese Academy of SciencesBeijing 100080China

An effective method was used to Ioidal suspensions of highly reduced graphene produce stable and homogeneous coloxide （RGO） in N,N-dimethylformamide （DMF） without the assistance of dispersing agents. According to the results of general characterization, relatively pure graphene sheets with the morphology of single layer or few-layer structure were obtained. Then nanocomposite powders of RGO and poly （vinylidene fluoride）（PVDF） were prepared by vacuum filtration of the mixed dispersions of both components. The nanocomposites exhibit a high-frequency capacitative response with small equivalent series resistance （ESR） at 0.4Q, a nearly rectangular cyclic voltammogram and possess a rapid current response as electrodes for supercapacitor in 5mol/L KOH electrolyte. Furthermore, after 600 galvanostatic charge/ discharge cycles, the supercapacitor still performs a very high stability and efficiency of capacitance.

关键词： reduced graphene oxide (RGO) poly(vinylidene fluoride) (PVDF) nano.,composite supercapacitor