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NUMERICAL SIMULATION AND EXPERIMENTAL STUDY OF DRAGREDUCING SURFACE OF A REAL SHARK SKIN

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Journal of Hydrodynamics 2011年第2期23卷 204-211页

作者： ZHANG De-yuan LUO Yue-hao li Xiang chen hua-wei School of Mechanical Engineering and Automation Beihang University Beijing 100191 China

It is well known that shark skin surface can effectively inhabit the occurrence of turbulence and reduce the wall friction, but in order to understand the mechanism of drag reduction, one has to solve the problem of the turbulent flow on grooved-scale surface, and in that respect, the direct numerical simulation is an important tool. In this article, based on the real biological shark skin, the model of real shark skin is built through high-accurate scanning and data processing. The turbulent flow on a real shark skin is comprehensively simulated, and based on the simulation, the drag reduction mechanism is discussed. In addition, in order to validate the drag-reducing effect of shark skin surface, actual experiments were carried out in water tunnel, and the experimental results are approximately consistent with the numerical simulation.

关键词： numerical simulation experimental study biomimetic surface shark skin drag reduction mechanism

Gastric metastasis presenting as submucosa tumors from renal cell carcinoma:A case report

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World Journal of Clinical Cases 2022年第27期10卷 9805-9813页

作者： Wen-Guo chen Guo-Dong Shan hua-Tuo Zhu li-hua chen Guo-Qiang Xu Department of Gastroenterology The First Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310003Zhejiang ProvinceChina

BACKGROUND Gastric metastasis from renal cell carcinoma(RCC) is an extremely rare clinical *** to an easily neglected RCC history,nonspecific symptoms and underrecognized endoscopic presentation may lead to a potential diagnostic pitfall in daily clinical *** SUMMARY We present a case of metastatic gastric tumors arising from RCC 5 years after radical ***,multifocal metastases to the gallbladder,pancreas and soft tissue were *** year previously,a solitary submucosal discoid tumor with a central depression was detected in the gastric fundus in a 65-year-old *** ultrasonography(EUS) showed a 1.12 x 0.38 cm lesion originating from the deeper mucosal layers with partially discontinuous *** year later,the endoscopic findings of the lesion showed various changes.A large lesion of the protruding type(2.5 cm × 2 cm) was found in the fundus at the same *** showed a heterogeneous mass that involved the mucosa and submucosal *** addition,two small similar submucosal lesions 0.4-0.6 cm in size were *** lesions had a central depression,surface mucosal congestion and thickened *** two adjacent lesions in the fundus were resected by endoscopic submucosal *** on the postoperative pathological analysis,the patient was diagnosed with gastric metastasis from *** Gastric metastasis from RCC should be considered in patients with a history of RCC irrespective of the time interval involved.

关键词： Gastric metastasis Renal cell carcinoma Nephrectomy Endoscopic ultrasonography Endoscopic submucosal dissection Case report

Large heterotopic gastric mucosa and a concomitant diverticulum in the rectum:Clinical experience and endoscopic management

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World Journal of Gastroenterology 2018年第30期24卷 3462-3468页

作者： Wen-Guo chen hua-Tuo Zhu Ming Yang Guo-Qiang Xu li-hua chen Hong-Tan chen Department of Gastroenterology The First Affiliated HospitalCollege of MedicineZhejiang University

Heterotopic gastric mucosa(HGM) in the rectum is an extremely rare clinical entity which may be missed or misdiagnosed due to a lack of *** the present study,a 14-year-old girl visited our hospital due to a 5-year history of repeated *** showed a solitary superficial depressed lesion approximately 5 cm in size and a concomitant 1.5 cm deep diverticulum in the *** examination of the endoscopic biopsy showed typical ectopic gastric mucosa in the depressed lesion and inside the *** band imaging further confirmed the histological *** ultrasound indicated that the lesion originated from the mucosal layer,and partially involved the submucosal *** submucosal dissection was performed in this patient due to the large size and shape of the *** bleeding,perforation or other adverse events were *** presence of HGM in the diverticular cavity greatly increased the surgical difficulty.A literature review was also carried out in our study.

关键词： Endoscopic submucosal dissection Rectum Helicobacter pylori Endoscopy Heterotopic gastric mucosa

Activity of Azoxystrobin and SHAM to Four Phytopathogens

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Agricultural Sciences in China 2009年第7期8卷 835-842页

作者： JIN li-hua chen Yu chen Chang-jun WANG Jian-xin ZHOU Ming-guo College of Plant Pathology Nanjing Agricultural University Nanjing 210095 P.R.China

The study was conducted to make clear the activity of azoxystrobin to 4 plant pathogens and the synergistic effects of salicylhydroxamic acid （SHAM）, which acted on the alternative oxidase. It was also conducted to be aware of the mechanism of azoxystrobin in inhibition on mycelial respiration and the influence of SHAM. The activity test of azoxystrobin and SHAM was carried out with a mycelial linear growth test and spore germination test. Other related biological properties were also observed. Inhibition of azoxystrobin and SHAM on 4 pathogens was determined by using SP-II oxygraph system. Azoxystrobin inhibited mycelial growth in Colletotrichum capsici, Botrytis cinerea, Rhizoctonia solani, and Magnaporthe grisea, respectively; it also inhibited conidia germination, and conidia production in C. capsici, B. cinerea M. grisea, and sclerotia formation in R. solani. Moreover, it created stayed pigment biosynthesis in C. capsici and M. grisea somehow. Salicylhydroxamic acid enhanced inhibition by azoxystrobin. An oxygen consuming test of the mycelia showed that azoxystrobin inhibited all the 4 fungi＇s respiration in the early stages. With the concentration rising up, the effectiveness increased. However, as time went on, the respiration of the mycelia treated with fungicides recovered and SHAM could not inhibit the oxygen consuming. This reaction between the mycelia and the fungicides appeared not to initiate alternative respiration but rather the other mechanism created a lack of efficacy.

关键词： azoxstrobin salicylhydroxamic acid (SHAM) plant pathogens spore germination mycelial growth oxygenconsumption rate

Production and Properties of a Thickener with Ability of Suspending Sand

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Journal of China University of Mining and Technology 2006年第2期16卷 115-118,122页

作者： QIN Bo-tao WANG De-ming li Zeng-hua chen jian-hua School of Mineral and Safety Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

To overcome the shortcomings of pouring sands, a thickener with the ability to suspend sands was developed. It is mixed with sands to form densified slurry, and can insure the sands against deposition, jamming pipelines and de- hydration. The chemical structure of the thickener is introduced in this paper and the production process is studied. The main processes include immersion, decomposition, dilution and addition of additives. In order to produce a thickener with high viscosity to suspend sands, key factors must be controlled in each process: the immersion time is 2 h; the mass fraction of formaldehyde is 0.01% and mass of NaCO3 accounts for 15% of dry material; the water temperature is 65 ℃ in summer and 72 ℃ in winter and the decomposition time is 2 h in the reaction; the densified decomposition so- lution should be diluted to 1% mass fraction; the additives of calcium ions and pH indicators must be added to the di- luted liquid; the mass fraction of CaCl2 is 0.048% and the pH value of the solution is 7.5. The thickener is a gel with three-dimensional network structure, a liquid with non-Newtonian behaviour and the characteristics of pseudo-plastic material, a solution with little resistance and the ability to revive its oral primary viscosity. It has been successfully ap- plied in Shendong Mines and has great value and wide-spread prospective use.

关键词： thickener ability of suspending sand spontaneous combustion of coal

Diagnostic accuracy of endoscopic ultrasonography for rectal neuroendocrine neoplasms

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World Journal of Gastroenterology 2014年第30期20卷 10470-10477页

作者： Hong-Tan chen Guo-Qiang Xu Xiao-Dong Teng Yi-Peng chen li-hua chen You-Ming li Department of Gastroenterology The First Affiliated Hospital of Zhejiang University School of Medicine Department of Pathology The First Affiliated Hospital of Zhejiang University School of Medicine

AIM: To investigate the diagnostic accuracy of endoscopic ultrasonography (EUS) for rectal neuroendocrine neoplasms (NENs) and the differential diagnosis of rectal NENs from other subepithelial lesions (SELs).

关键词： Rectum Neuroendocrine neoplasms Endoscopic ultrasonography Diagnosis

Improving anammox activity and reactor start-up speed by using CO_(2)/NaHCO_(3) buffer

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Journal of Environmental Sciences 2024年第5期139卷 60-71页

作者： Shaoan cheng huahua li Xinyuan He hua chen Longxin li State Key Laboratory of Clean Energy Utilization College of Energy EngineeringZhejiang UniversityHangzhou 310027China

Anammox bacteria grow slowly and can be affected by large pH *** suitable buffers could make the start-up of anammox reactors easy and *** this study,the effects of three kinds of buffers on the nitrogen removal and growth characteristics of anammox sludge were *** with CO_(2)/NaHCO_(3)buffer solution(CCBS)performed the best in nitrogen removal,while 4-(2-hydroxyerhyl)piperazine-1-ethanesulfonic acid(HEPES)and phosphate buffer solution(PBS)inhibited the anammox *** with 50 mmol/L CCBS could start up in 20 days,showing the specific anammox activity and anammox activity of 1.01±0.10 gN/(gVSS·day)and 0.83±0.06 kgN/(m^(3)·day),*** Kuenenia was the dominant anammox bacteria,with a relative abundance of 71.8%.Notably,anammox reactors could also start quickly by using 50 mmol/L CCBS under nonstrict anaerobic *** findings are meaningful for the quick start-up of engineered anammox reactors and prompt enrichment of anammox bacteria.

关键词： Anammox bacteria Buffer solution CO_(2)/NaHCO_(3) Physiological characteristics Microbial community shift

New Approach to the Synthesis of C-Glycosides

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复旦学报（自然科学版） 2005年第5期44卷 724-725页

作者： Xiaoliu li Kefang Duan Zhiwei li Haiyang liu hua chen School of Chemistry and Environmental Sciences Hebei University Baocling Hebei 071002 China

C-glycosides are important carbohydrate mimetics and have gained considerable attention because of their attractive biological activities as pharmaceutical targets and their resistance to enzymatic degradation in ***, a large number of C-glycosides have been synthesized for their bioactivity investigation, and various synthetic methodologies have been developed[1,2]. As a continuation of the synthesis of novel C-glycoside derivatives using exo-glycals as the precursor[3,4], we wish to present herein new approaches to the synthesis of C-aryl aminoglycoside via the 1,3-dipolar cycloaddition (Scheme 1 ) and C-disaccharides by Suzuki cross-coupling reaction (Scheme 2), and the synthesis of dihydropyrimidinonyl (DHPM) glycoside by the three component Biginelli reaction[5] (Scheme 3).

关键词：配糖碳水化合物合成方法烯糖

A Novel Synthesis of Two-dimensional Nanopatterned TiO_(2)Thin Film

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Chinese Chemical Letters 2006年第8期17卷 1085-1088页

作者： Ming Xian liU li hua GAN Gen chen Zi Jie XU Zhi Xian HAO Long Wu chen Department of Chemistry Tongji University Shanghai 200092

A novel two-dimensional nanopattemed TiO2 thin film has been synthesized through the interaction between cationic Gemini surfactant molecules and the prepared TiO2 colloid nanoparticles with average diameters of 8 nm by controlling the surface pressure of the monolayer. TEM photographs from the formed Gemini-TiO2 composite monolayer confirm that the prepared TiO2 film is of a branch nanopattern.

关键词： Two-dimensional nanopattern TiO2 thin film Gemini surfactant.