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PRESSURE CHARACTERISTICS OF CAVITATION CONTROL BY AERATION

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Journal of Hydrodynamics 2005年第6期17卷 764-769页

作者： dong Zhi-yong LU yang-quan JU Wen-jie CAI Xin-ming DING Chun-sheng School of Civil and Architectural Engineering Zhejiang University of Technology Hangzhou 310032 China

This experimental investigation was systernatically conducted with the aid of a non-circulating water tunnel in the Hydraulics Laboratory at Zhejiang University of Tech nology in China, The test velocity is between 20m/s and 40m/ s. The least air concentration to prevent cavitation erosion lies between 1. 7% and 4. 5%. Pressure waveforms with and without aeration in cavitation and cavitation erosion regions were measured. Time-averaged pressure profiles with and without aeration were compared. Pressure characteristics cotresponding to least air concentration to prevent cavitation erosion in cavitation and cavitation erosion regions were analyzed.

关键词： pressure increase compression wave cavitation control by aeration least air concentration eavitation number

Tanshinone ⅡA improves functional recovery in spinal cord injury-induced lower urinary tract dysfunction

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Neural Regeneration Research 2017年第2期12卷 267-275页

作者： yong-dong yang Xing Yu Xiu-mei Wang Xiao-hong Mu Feng He Department of Orthopedics Dongzhimen Hospital Beijing University of Chinese Medicine School of Materials Science and Engineering Tsinghua University

Tanshinone ⅡA, extracted from Salvia miltiorrhiza Bunge, exerts neuroprotective effects through its anti-inflammatory, anti-oxidative and anti-apoptotic properties. This study intravenously injected tanshinone ⅡA 20 mg/kg into rat models of spinal cord injury for 7 consecutive days. Results showed that tanshinone ⅡA could reduce the inflammation, edema as well as compensatory thickening of the bladder tissue, improve urodynamic parameters, attenuate secondary injury, and promote spinal cord regeneration. The number of hypertrophic and apoptotic dorsal root ganglion（L6–S1） cells was less after treatment with tanshinone ⅡA. The effects of tanshinone ⅡA were similar to intravenous injection of 30 mg/kg methylprednisolone. These findings suggested that tanshinone ⅡA improved functional recovery after spinal cord injury-induced lower urinary tract dysfunction by remodeling the spinal pathway involved in lower urinary tract control.

关键词： nerve regeneration spinal cord injury tanshinone IIA spinal pathway lower urinary tract dysfunction neurogenic bladder dorsal root ganglion detrusor-sphincter dyssynergia urodynamics neural regeneration

Extending the trapping lifetime of single atom in a microscopic far-off-resonance optical dipole trap

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Frontiers of physics 2011年第3期6卷 262-270页

作者： Jun HE Bao-dong yang yong-jie CHENG Tian-cai ZHANG Jun-min WANG State Key Laboratory of Quantum Optics and Quantum Optics Devices and Institute of Opto Electronics Shanxi University Taiyuan 030006 China

In our experiment, a single cesium atom prepared in a large-magnetic-gradient magneto optical trap （MOT） can be efficiently transferred into a 1064-nm far-off-resonance microscopic optical dipole trap （FORT）. The efficient transfer of the single atom between the two traps is used to determine the trapping lifetime and the effective temperature of the single atom in FORT. The typical trapping lifetime has been improved from ~ 6.9 s to ~ 130 s by decreasing the background pressure from 1 × 10^-10 Torr to ~ 2 × 10^-11 Torr and applying one-shot 10-ms laser cooling phase. We also theoretically investigate the dependence of trapping lifetimes of a single atom in a FORT on trap parameters based on the FORT beam＇s intensity noise induced heating. Numerical simulations show that the heating depends on the FORT beam＇s waist size and the trap depth. The trapping time can be predicted based on effective temperature measurement of a single atom in the FORT and the intensity noise spectra of the FORT beam. These experimental results are found to be in agreement with the predictions of the heating model.

关键词： magneto optical trap (MOT) far-off-resonance optical dipole trap (FORT) singleatom trapping lifetime release-and-recapture method (R&R) effective temperature

Characterizations of VMO and CMO Spaces in the Bessel Setting

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Acta Mathematica Sinica,English Series 2024年第12期40卷 3055-3078页

作者： Qing dong GUO Jorge J.BETANCOR dong yong yang School of Mathematical Sciences Xiamen UniversityXiamen361005P.R.China Departamento de Anáisis Matemáico Universidad de La LagunaCampus de AnchietaAvda.Astrofísico Francisco Sánchezs/n38271La Laguna(Sta.Cruz de Tenerife)Spain

Letλ>0 and △λ:=-dx^(2)/d^(2)-x/2λdx/d be the Bessel operator on ℝ+:=(0,∞).In this paper,the authors introduce and characterize the space VMO(ℝ+,dmλ)in terms of the Hankel translation,the Hankel convolution and a John-Nirenberg inequality,and obtain a sufficient condition of Fefferman-Stein type for functions f∈VMO(ℝ+,dmλ)using R△λ,the adjoint of the Riesz transform R△λ.Furthermore,we obtain the characterization of CMO(ℝ+,dmλ)in terms of the John-Nirenberg inequality which is new even for the classical CMO(ℝ^(n))and a sufficient condition of Fefferman-Stein type for functions f∈CMO(ℝ+,dmλ).

关键词： Bessel operator VMO(ℝ+,dmλ) CMO(ℝ+,dmλ) Riesz transform

Weighted estimates for commutators of singular integral operators with non-doubling measures

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Science China Mathematics 2007年第11期50卷 1621-1641页

作者： Guo-en HU~1 Da-chun yang~(2+) dong-yong yang~2 1 Department of Applied Mathematics,University of Information Engineering,Zhengzhou 450002,China 2 School of Mathematical Sciences,Beijing Normal University,Beijing 100875,China Department of Applied Mathematics University of Information Engineering Zhengzhou China School of Mathematical Sciences Beijing Normal University Beijing China

Letμbe a nonnegative Radon measure on R^d which only satisfiesμ(B(x,r))≤C_0r^n for all x∈R^d,r>0,and some fixed constants C_0>0 and n∈(0,d].In this paper,some weighted weak type estimates with A_(p,(log L)~σ)~ρ(μ) weights are established for the commutators generated by Calder■n-Zygmund singular integral operators with RBMO(μ) functions.

关键词： non-doubling measure weight singular integral operator commutator

Transurethral dividing vaporesection for the treatment of large volume benign prostatic hyperplasia using 2 micron continuous wave laser

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Chinese Medical Journal 2010年第17期123卷 2370-2374页

作者： SUN dong-chong yang yong WEI Zhi-tao HONG Bao-fa ZHANG Xu Department of Urology General Hospital of Chinese People's Liberation Army Beijing 100853 China

Background The safety and efficiency of transurethral laser resection of the prostate to treat benign prostatic hyperplasia have been verified. However, this method does still not manage large volume prostates efficiently. To tackle this problem, we have designed a method of ＂transurethral dividing vaporesection of prostate＂ using a 2 micron continuous wave laser. The aim of this study was to evaluate the safety and efficiency of this method in the management of large prostates （〉80 ml）.Methods In this study, 45 cases of benign prostatic hyperplasia with a median prostatic volume of （123.7±26.7） ml （range, 80.2-159.8 ml） were treated by the same surgeon under epidural anesthesia. During the surgery, superapubic catheters were needed, and saline solution was used for irrigation. First, the prostate was divided longitudinally into several parts from the bladder neck to the prostatic apex, and then gradually incised transversely chip by chip. Intraoperative blood transfusion rate, postoperative complications, maximum urinary flow rate, International Prostate Symptom Score and quality of life scores were recorded for statistical analysis using SPSS 16.0 *** Intraoperatively, no transurethral resection syndrome was observed, and no blood transfusions were *** resected prostatic chips were easily flushed out of the bladder through the resectoscope sheath without the use of a morcellator. Median vaporesection time was （95.0±13.2） minutes （range, 75-120 minutes）, and the median retrieved and removed prostatic tissue were （25.2±5.1） g （range, 15.5-34.7 g） and （75.4±16.4） g （range, 43.8-106.1 g）, respectively. Median catheter time and hospital stay were （3.3±0.9） days （range, 3-5 days） and （4.8±1.8） days （range, 3-9 days）, respectively. After a follow-up of 6 to 12 months, two patients had stress urinary incontinence and three had anterior urethral strictures. Satisfactory improvement was seen in maximum urinary flow rate, International Prostate Symptom Sc

关键词： 2 micron continuous wave laser vaporesection benign prostatic hyperplasia

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氧化石墨烯对L-色氨酸荧光猝灭及机理研究

新型炭材料 2016年第6期31卷 639-645页

作者：弓巧娟王永东杨海英原梅妮运城学院应用化学系山西运城044000 山西大学化学化工学院山西太原030006 中北大学机电工程学院山西太原030051

采用改进的Hummers法制备氧化石墨烯,并用红外、拉曼光谱和扫描电镜等手段对氧化石墨烯的结构及形貌进行表征,考察了不同溶剂对L-色氨酸荧光光谱的影响;分别以L-色氨酸、氧化石墨烯为荧光剂和荧光猝灭剂,借助荧光光谱法研究了氧化石墨烯... 详细信息

采用改进的Hummers法制备氧化石墨烯,并用红外、拉曼光谱和扫描电镜等手段对氧化石墨烯的结构及形貌进行表征,考察了不同溶剂对L-色氨酸荧光光谱的影响;分别以L-色氨酸、氧化石墨烯为荧光剂和荧光猝灭剂,借助荧光光谱法研究了氧化石墨烯对L-色氨酸的荧光猝灭作用。根据紫外吸收光谱、Stern-Volmer方程和Lineweawer-Burk双倒数曲线方程,得出了氧化石墨烯对L-色氨酸荧光猝灭类型、猝灭速率常数(k_q)和结合常数(K)等参数。结果表明,氧化石墨烯对L-色氨酸的荧光有较强的猝灭作用,其荧光猝灭机理是氧化石墨烯与L-色氨酸形成复合物的静态猝灭。

关键词：氧化石墨烯 L-色氨酸荧光猝灭

Merging polymers of intrinsic microporosity and porous carbon-based zinc oxide composites in novel mixed matrix membranes for efficient gas separation

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Green Energy & Environment 2025年第1期10卷 203-213页

作者： Muning Chen Jiemei Zhou Jing Ma Weigang Zheng Guanying dong Xin Li Zhihong Tian Yatao Zhang Jing Wang yong Wang School of Chemical Engineering Zhengzhou UniversityZhengzhou450001HenanChina State Key Laboratory of Materials-Oriented Chemical Engineering and College of Chemical Engineering Nanjing Tech UniversityNanjing211816JiangsuChina Singapore Membrane Technology Centre Nanyang Environment and Water Research InstituteNanyang Technological UniversitySingapore637141Singapore Engineering Research Center for Nanomaterials Henan UniversityKaifeng475004HenanChina State Key Laboratory of Coking Coal Resources Green Exploitation Zhengzhou UniversityZhengzhou 450001China School of Energy and Environment Southeast UniversityNanjing210096JiangsuChina

Mixed matrix membranes(MMMs)have demonstrated significant promise in energy-intensive gas separations by amalgamating the unique properties of fillers with the facile processability of ***,achieving a simultaneous enhancement of permeability and selectivity remains a formidable challenge,due to the difficulty of achieving an optimal match between polymers and *** this study,we incorporate a porous carbon-based zinc oxide composite(C@ZnO)into high-permeability polymers of intrinsic microporosity(PIMs)to fabricate *** dipole–dipole interaction between C@ZnO and PIMs ensures their exceptional compatibility,mitigating the formation of non-selective voids in the resulting ***,C@ZnO with abundant interconnected pores can provide additional low-resistance pathways for gas transport in *** a result,the CO_(2) permeability of the optimized C@ZnO/PIM-1 MMMs is elevated to 13,215 barrer,while the CO_(2)/N_(2) and CO_(2)/CH4 selectivity reached 21.5 and 14.4,respectively,substantially surpassing the 2008 Robeson upper ***,molecular simulation results further corroborate that the augmented membrane gas selectivity is attributed to the superior CO_(2) affinity of C@*** summary,we believe that this work not only expands the application of MMMs for gas separation but also heralds a paradigm shift in the application of porous carbon materials.

关键词： Mixed matrix membranes Polymers of intrinsic microporosity CO_(2)separation Porous carbon materials

Design and Applications of Land Resources and Ecological Environment Information System: A Case Study of Zigui County in the Three Gorges Area of China

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Pedosphere 2002年第4期12卷 373-381页

作者： ZHOUyong WANGSHANQIN dongYUANHUA yangLINZHANG InsitituteofSoilScience theChineseAcademyofSciencesP.O.Box821Nanjing210008（China） KeyLabofSubtropicalSoilResourcesandEnvironment theMinistryofAgricultureWuhan430070（China）

The design and applications of a land information system built upon ARC/INFO and ArcView are presented. The proposed system not only maintains all the advantages of the more conventional implementations but also enhances them in the following ways: 1) the application program interfaces (API) are used to transmit data and messages among different parts of the system; 2) the integrated system can support studies on land evaluations and ecological analyses by efficient management of attribute and spatial data and 3) correspondingly, spatial records and attributive records are linked by the same identifiers (ID). A case study application in Zigui County of the Three Gorges Area in China demonstrates that the system could employ land-use maps and land property data to predicate and analyze the land utilization changes in the past, present and future. The ecological environment analysis can be carried out with the data of land, economics and terrain map used, showing that the system can be widely applied, especially to survey land and environment resources in the countryside area.

关键词： attribute database ecological environment land resources spatial database