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Grinding Properties of Abandoned Concrete

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Journal of China University of Mining and Technology 2007年第2期17卷 281-285页

作者： ZHENG Fang-yu wang li-jiu li qiang School of Civil and Hydraulic Engineering Dalian University of Technology Dalian Liaoning 116024 China

The grinding properties of abandoned concrete, which consists primarily of hardened cement, limestone aggregate and river sand, are studied. Theoretical models of grinding are used to explain the experimental observation. The results show that 1) The principle disintegration mechanism of hardened cement and river sand is volumetric grinding, although at later stages grinding of cement becomes difficult because of its flaked structure; 2) The lime- stone grinding process can be divided into two steps. First, volumetric grinding, with an obvious component of surface grinding, followed by primarily surface grinding as the micro-particle content increases; 3) Initially, the principle mechanism of grinding limestone and river sand is volumetric grinding, albeit less efficient grinding than if these components were ground separately, and; 4) After 10 to 20 min of grinding the grinding bottleneck phenomenon ap- pears and after 20 min of grinding the content of micro-particles is large and surface grinding is the main mechanism while the particle size of the mixture is smaller than that of separately ground river sand and cement but bigger than that of separately ground limestone.

关键词： abandoned concrete cement stone limestone river sand grinding

Synthesis, Crystal Structure and Insecticidal Activities of Novel Neonicotinoid Derivatives

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Chemical Research in Chinese Universities 2010年第3期26卷 380-383页

作者： ZHAO Yu wang Gang li Yong-qiang wang Su-hua li Zheng-ming State Key Laboratory of Elemento-Organic Chemistry Research Institute of Elemento-Organic Chemistry National Pesticide Engineering Research Center（Tianjin） Nankai University Tianjin 300071 P. R. China

Ten new N-oxalyl derivatives of neonicotinoid compound were designed and synthesized. Their structures were confirmed by ^1H NMR spectra, elemental analysis and X-ray diffraction. The preliminary insecticidal activities of the new compounds were evaluated. The results of bioassays indicate that the title Compounds exhibit moderate insecticidal activities. Surprisingly, the insecticidal activity of compound 7b against bean aphids at 200 mg/kg is 100%, which is comoarable to that of the commercialized imidacloprid.

关键词： Neonicotinoid N-Oxalyl derivative Insecticidal activity Bean aphid Imidacloprid

A simulation study of rapid solidification and crystal configuration of Cu_(70)Ni_(30) alloy

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Science China(Physics,Mechanics & Astronomy) 2005年第6期48卷 687-694页

作者： ZHENG Caixing liU Rangsu ZHOU Qunyi TIAN Ze'an wang Xin li qiang Department of Physics Hunan University Changsha 410082 China Department of Physics Hunan University Changsha 410082 China Department of Physics Hunan University Changsha 410082 China Department of Physics Hunan University Changsha 410082 China Department of Physics Hunan University Changsha 410082 China Department of Physics Hunan University Changsha 410082 China

A molecular dynamics (MD) simulation study has been performed for the rapid solidification of Cu70Ni30 adopting the quantum Sutton-Chen many-body potentials. By analyzing the bond-types and the relation of atomic average energy versus temperature, it was demonstrated that as cooling rate being 2 × 1012 K/s, the Cu70Ni30 formed fcc crystal structures and freezing point was found. In addition, having analyzed the transformation of microstructures and the detail of crystal growth by using atomic trace and visual method, not only could the formation of binary disordered solid solution be showed, but also the solidification of liquid metals and the crystal growth processes could be further understood.

关键词： quantum Sutton-Chen potentials, molecular dynamics simulation, Cu70Ni30 alloy, rapid solidification.

COLOR CORRECTION FOR HIGH-DEFINITION ELECTRONIC ENDOSCOPE

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Journal of Innovative Optical Health Sciences 2012年第4期5卷 57-63页

作者： CHEN JING wang li-qiang MENG ZI-BO YUAN BO DUAN HUI-LONG State Key Laboratory of Modern Optical Instrumentation Zhejiang University HangzhouZhejiang 310027P.R.China Biomedical Engineering Institute Zhejiang University HangzhouZhejiang 310027P.R.China

The subtle color distinction is the important function of electronic endoscope imaging ***,after image acquisition,transmission and display,color distortions of intracorporeal organs or tissues occur inevitably,which are adverse to analyze image features accurately or to diagnose early pathological changes.A real-time color correction algorithm based on fourneighborhood and polynomial regression in YUV color space is *** on polynomial regression the color correction matrix is calculated in YUV color space according to the dierences between standard values of color checker and measured values of that imaged by the *** the correction is only executed on U and V components in YUV color space,the defect that the color of corrected images in RGB color space will change along with luminance can be avoided,and then the stability of image color is *** to four-neighborhood processing,the signal-to-noise ratio of corrected images is enhanced and the processing speed of correction algorithm is *** average color dierence is reduced from 0.3944 to 0.2850 by application of the proposed algorithm in high-denition electronic endoscope.A total of 17 frames per second can be achieved at the resolution of 1280800,and the color characteristics of the image after processing match that of human visual system.

关键词： High-de¯nition electronic endoscope color correction polynomial regression fourneighborhood

Quaternary marine ostracoda on the west coast of the Bohai Sea

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Acta Oceanologica Sinica 1988年第1期7卷 94-103页

作者： wang qiang, li Yude, Tian Guoqiang and lin Fang China

According to the results of analysis of the marine ostracoda biofacies from over 160 drilled holes on the west coast of the Bohai Sea, i.e. Hebei and Shandong Provinces, Tianjin, and the east part of Beijing, the present paper is a discussion of their palaeoecological and stratigraphigical significance. The investigation of ostracoda thanatocoenoces in the modern coastal zone suggests that the distribution of marine ostracoda has been controlled by the salinity and depth of water. The study of Quaternary marine ostracoda should be concentrated mainly on the determination of their biofacies and palaeogeographigical conditions, so as to provide evidence for the determination of transgression range, palaeoshoreline and sca-leve! changes.

关键词： wang Quaternary marine ostracoda on the west coast of the Bohai Sea

Effects of adenovirus-mediated human cyclooxygenase-2 antisense RNA on the growth of hepatocellular carcinoma

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World Journal of Gastroenterology 2005年第39期11卷 6110-6114页

作者： Xiao-Hu wang Sheng-Bao li qiang Tong Guo-Jian Xie Qing-Ming Wu Department of Gastroenterology Taihe Hospital Yunyang Medical College Shiyan 442000 Hubei Province China

AIM: To investigate the relation between the expression of cyclooxygenase-2 (COX-2) and liver cancer, to construct the recombinant adenovirus encoding human COX-2antisense RNA, and to explore its effects on liver cancer cell ***: We studied the expression of COX-2 in 34cases of hepatocellular carcinoma (HCC) and SMMC7402and SMMC7721 by immunohistochemical *** adenovirus Ad-AShcox-2 was constructed and transfected into human HCC cell lines SMMC7402and SMMC7721, and its effects on COX-2 expression, cell apoptosis and cell cycle were analyzed by flow *** proliferation was determined by colony-forming ***: We observed COX-2 expression in 82.4% of HCC and SMMC7402 cells, but no COX-2 expression in SMMC7721 cells. In addition, recombinant adenovirus encoding antisense COX-2 fragment Ad-AShcox-2 was obtained with the titer of 1.06× 1012 PFU/mL. Ad-AShcox-2 could reduce the expression of COX-2 and enhance the percentage of cells in G1/G0 phase in SMMC7402 cell *** difference of apoptotic index between the Ad-AShcox2 group and control group was statistically significant(tcontrol group= 32.62 and tAd-LacZ= 10.93, P＜0.001) in SMMC7402 but not in SMMC7721. Similarly, colony-forming rates of SMMC7402 and SMMC7721 cell lines, after the transfer of Ad-AShcox-2, were (2.7±0.94)% and(33.6±4.24)%, ***: Reduction in the expression of COX-2 can inhibit COX-2 expressing HCC cells.

关键词： Adenovirus Cyclooxygenase-2 Antisense RNA Hepatocellular carcinoma

Formulation of dried lignans nanosuspension with high redispersibility to enhance stability,dissolution,and oral bioavailability

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Chinese Journal of Natural Medicines 2016年第10期14卷 757-768页

作者： SHEN Gang CHENG ling wang li-qiang ZHANG li-Hong SHEN Bao-De liAO Wei-Bo li Juan-Juan ZHENG Juan XU Rong YUAN Hai-Long Department of Pharmacy Air Force General Hospital of PLABeijing 100142China Pharmacy College Chengdu University of Traditional Chinese MedicineChengdu 611137China School of Biomedical Sciences Huaqiao UniversityQuanzhou 362021China

Herpetospermum caudigerum lignans(HTL), one of the potential drugs with anti-hepatitis B virus and hepatoprotective effects, has limited clinical applications because of poor aqueous solubility and low bioavailability. Both herpetrione(HPE) and herpetin(HPN) are the most abundant ingredients in HTL and exhibit weak acidity. The purpose of the present study was to produce dried preparations of HTL(composed of HPE and HPN) nanosuspensions(HTL-NS) with high redispersibility using lyophilization technology. The HTL-NS was prepared by utilizing precipitation-combined homogenization technology based on acid-base neutralization reactions, and critical formulation and process parameters affecting the characteristics of HTL-NS were optimized. The resultant products were characterized by particle size analysis, SEM, XRD, stability, solubility, dissolution and in vivo bioavailability. HTL-NS showed near-spherical-shaped morphology and the size was 243 nm with a narrow PDI value of 0.187. The dried preparations with a relatively large particle size of 286 nm and a PDI of 0.215 were achieved by using 4%(W/V) mannitol as cryoprotectants, and had a better stability at 4 or 25 oC for 2 months, compared to HTL-NS. In the in vitro test, the dried preparations showed markedly increased solubility and dissolution velocity. Besides, in the in vivo evaluation, it exhibited significant increases in AUC0–t, C_(max), MRT and a decrease in T_(max), compared to the raw drug.. In conclusion, our results provide a basis for the development of a drug delivery system for poorly water-soluble ingredients with p H-dependent solubility.

关键词： Herpetospermum caudigerum lignans Nanosuspensions Acid-base neutralization Saturation solubility Dissolution Oral bioavailability

Study of dynamic pressure roadway supporting scheme under condi- tion of thick composite roof

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Journal of Coal Science & Engineering(China) 2013年第2期19卷 119-125页

作者： Wei-Jun wang li-qiang LUO Wei-Jian YU Hai WU Yan-Si QU Hunan Provincial Key Laboratory of Safe Mining Techniques of Coal Mines Hunan University of Science and TechnologyXiangtan 411201 China

This paper analyzed the strata behaviors of solid-coal roadway, gob-side entry driving and deformation law of surrounding rock in depth under high stress and thick composite roof based on the dynamic pressure roadway as engineering background in Fengcheng mining area, Jiangxi province. The results, both field measurement and numerical simulation show that gob-side entry driving results the deformation of coal roadway main wall, however, entity-coal roadway driving results deformation of main roof and floor. The maintenance state of gob-side entry driving is better than entity-coal roadway, this situation is relevant to thick composite roof layered and easy collapse characteristics. At the same time, this paper put fox＇ward and proved proper dynamic pressure roadway supporting scheme under the surrounding rock condition and stress environment.

关键词： thick composite roof dynamic pressurized roadway high stress surrounding rock control

Effects of prior freezing or drying on the swelling behaviour of the bovine cornea

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Chinese Medical Journal 2009年第2期122卷 212-218页

作者： HUANG Yi-fei Keith M. Meek wang li-qiang wang Da-jiang Department of Ophthalmology Chinese PLA General Hospital Beijing 100853 China Department of Optometry and Vision Sciences University of Cardiff Cardiff CF1 3AT United Kingdom

Background Frozen or dried corneal grafts are commonly used for stromal transplantation such as lamellar keratoplasty （full or partial thickness）, keratophakia, epikeratophakia. Structural properties are important for the final optical results of these surgeries but the effects of freezing/thawing and drying/rehydration on the properties of the stroma are known little compared with the corneal endothelium, mainly because of lack of non-invasive technique to evaluate the stromal structure. This study aimed to investigate the swelling and structural properties of the bovine corneal stroma following freezing or drying by X-ray diffraction which was a non-invasive technique and could give ultra-structural information in hydrated tissues. Methods Bovine corneas were either frozen at -40~C or dried to constant weight in a dessicator over silica gel. Swelling was carried out by placing the corneas into dialysis tubing and equilibrating them against various concentrations of polyethylene glycol （PEG） to obtain a range of tissue hydrations. This method minimises the loss of soluble tissue components during the swelling process. Synchrotron X-ray diffraction was used to measure the average intermolecular spacing, the interfibrillar spacing and the fibril diameter as a function of hydration. Changes in light scattering were detected using a microdensitometer. Results Freezing and thawing of the cornea caused an increase in light scattering by 63.9% at tissue hydration （H）=3.4, and by 50.0% at H=4.9. Repeated freezing and thawing causes further increased by 38.9% at the second time and another 36.0% at the third time （P 〈0.05）. There was a tendency for both the frozen and the dried comeas to lose some swelling ability, achieving hydrations respectively of 10% and 18% below those of fresh corneas at 0 PEG. There were no changes in the fibril diameters, interfibrillar or intermolecular spacings as measured by X-ray diffraction in the equilibrated fresh, pre-frozen and pre-dried c

关键词： cornea freezing stroma swelling X-ray diffraction