检索结果-南通市图书馆

Acoustics Based Monitoring and Diagnostics for the Progressive Deterioration of Helical Gearboxes

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2021年第4期34卷 98-109页

作者： Kaibo Lu James xi gu Hongwei Fan xiuquan Sun Bing Li Fengshou gu College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024China School of Engineering University of BoltonBolton BL35ABUK College of Mechanical Engineering Xi’an University of Science and TechnologyXi’an 710054China Centre for Efficiency and Performance Engineering University of HuddersfieldHuddersfield HD13DHUK. School of Industrial Automation Beijing Institute of TechnologyZhuhai 519088China

Gearbox condition monitoring(CM)plays a significant role in ensuring the operational reliability and efficiency of a wide range of critical industrial systems such as wind turbines and *** and timely diagnosis of gear faults will improve the maintenance of gearboxes operating under sub-optimal conditions,avoid excessive energy consumption and prevent avoidable damages to *** study focuses on developing CM for a multi-stage helical gearbox using airborne *** on signal phase alignments,Modulation Signal Bispectrum(MSB)analysis allows random noise and interrupting events in sound signals to be suppressed greatly and obtains nonlinear modulation features in association with gear *** coherence is evaluated for selecting the reliable bi-spectral peaks for indication of gear deterioration.A run-to-failure test of two industrial gearboxes was tested under various loading *** omnidirectional microphones were fixed near the gearboxes to sense acoustic information during *** has been shown that compared against vibration based CM,acoustics can perceive the responses of vibration in a larger areas and contains more comprehensive and stable information related to gear dynamics variation due to ***,the MSB magnitude peaks at the first three harmonic components of gear mesh and rotation components are demonstrated to be sufficient in characterizing the gradual deterioration of gear ***,the combining of MSB peaks with baseline normalization yields more accurate monitoring trends and diagnostics,allowing the gradual deterioration process and gear wear location to be represented more consistently.

关键词： Acoustics Modulation Signal Bispectrum Helical gearbox Gear wear

TMSOTf-catalyzed intramolecular seleno-arylation of tethered alkenes:A novel method for the solid-phase synthesis of dihydrocoumarins and coumarins

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2012年第6期23卷 631-634页

作者： E Tang Wen Li Zhang Yong Gao xi gu Key Laboratory of Medicinal Chemistry of Natural Resource （Yunnan University） Ministry of Education China Department of Applied Chemistry Yunnan University Kunming 650091 China

TMSOTf-catalyzed intramolecular seleno-arylation of tethered alkenes was performed using polystyrene-supported succini- midyl selenide as the selenium source. This catalytic process provides an efficient method for the regioselective synthesis of dihydrocoumarins possessing a seleno-functionality, followed by traceless cleavage of selenium linker to provide dihydrocoumar- ins and coumarins in good yields and purifies.

关键词： Lewis acid Seleno-arylation Succinimidyl selenide Solid-phase synthesis Dihydrocoumarins Coumarins

Palladium-assisted Metal Patterning on Polyimide Surfaces

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2022年第10期40卷 1287-1296,I0011页

作者： Shi-Long Zhong Bai-Yang Zhou xi-Rui gu Ding-Shan Yu Xu-Dong Chen Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education Key Laboratory of High Performance Polymer-based Composites of Guangdong Province School of Chemistry Sun Yat-sen UniversityGuangzhou 510275China

A novel method of patterning high precision copper conductive micropatterns on flexible polymer substrate(polyimide)is *** utilized the coordination effect between palladium salts and pyridine structures to fix the palladium chloride(PdCl_(2))on the surface of polymer film while the 2,6-dimethylpyridine structures formed in the specific areas under ultraviolet light guaranteed the resolution of final *** thermal reduction of PdCl_(2) on the surface can be achieved in the process of thermal cyclization of the polymer *** a consequence,the obtained polyimide(PI)film can be patterned with conductive copper micropatterns directly by electroless *** particular,we accomplished the deposition of high precision copper pattern with a minimum line width of 50μm and minimum line spacing of 20μm on PI thin films(thickness~10μm)by electroless *** prepared conductive copper micropatterns exhibit a low resistivity of 1.78μΩ·cm the same as the pure block *** the relationship between the structures of the polymer chains and the physical properties of polymer substrates,such as the dimensional stability,mechanical and dielectric properties were also discussed in *** simple and novel method of patterning metal on the polymer surface does not need to achieve the catalytic metal adhesion required for electroless plating at the cost of destroying the substrate surface and avoiding the introduction of unstable *** patterning method is compatible with the current roll-to-roll production process and can be used to develop high-performance micro-integrated circuits.

关键词： Polyimide Metal patterning Electroless plating Palladium chloride Coordination effect

Investigating design principles of micropatterned encapsulation systems containing high-density microtissue arrays

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2014年第2期57卷 221-231页

作者： JIANG LiYang LIU JiaYing WANG Kai gu xi LUO Ying Department of Biomedical Engineering College of Engineering Peking University National Engineering Laboratory for Regenerative and Implantable Medical Devices

Immunoisolation is an important strategy to protect transplanted cells from rejection by the host immune ***,microfabrication techniques have been used to create hydrogel membranes to encapsulate microtissue in an arrayed *** method illustrates a new macroencapsulation paradigm that may allow transplantation of a large number of cells with microscale spatial control,while maintaining an encapsulation device that is easily maneuverable and remaining integrated following *** study aims to investigate the design principles that relate to the translational application of micropatterned encapsulation membranes,namely,the control over the transplantation density/quantity of arrayed microtissues and the fidelity of pre-formed microtissues to *** hydrogel membranes with microwell patterns were used as a model encapsulation system to exemplify these *** results show that high-density micropatterns can be generated in hydrogel membranes,which can potentially maximize the percentage volume of cellular content and thereby the transplantation efficiency of the encapsulation *** seeding of microtissues demonstrates that microwell structures can efficiently position and organize pre-formed microtissues,suggesting the capability of micropatterned devices for manipulation of cellular transplants at multicellular or tissue *** theoretical analysis was performed to provide insights into the relationship between micropatterns and the transplantation capacity of membrane-based *** study lays the ground for developing new macroencapsulation systems with microscale cellular/tissue patterns for regenerative transplantation.

关键词： hydrogel micropattern array multi-cellular spheroids macroencapsulation

Astaxanthine attenuates cisplatin ototoxicity in vitro and protects against cisplatin-induced hearing loss in vivo

在线全文

学校读者我要写书评

暂无评论

Acta Pharmaceutica Sinica B 2022年第1期12卷 167-181页

作者： Benyu Nan Zirui Zhao Kanglun Jiang xi gu Huawei Li xinsheng Huang Department of Otorhinolaryngology-Head and Neck Surgery Zhongshan HospitalFudan UniversityShanghai 200030China Department of Otorhinolaryngology-Head and Neck Surgery Wenzhou Medical UniversityAffiliated Hospital 2Wenzhou 325000China Department of Otolaryngology Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghai 200437China Department of Otolaryngology the First Affiliated Hospital of Fujian Medical UniversityFuzhou 350005China ENT Institute and Department of Otorhinolaryngology Eye&ENT HospitalState Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain ScienceFudan UniversityShanghai 200031China Institutes of Biomedical Sciences Fudan UniversityShanghai 200031China NHC Key Laboratory of Hearing Medicine(Fudan University) Shanghai 200031China The Institutes of Brain Science and the Collaborative Innovation Center for Brain Science Fudan UniversityShanghai 200031China

Astaxanthine(AST) has important biological activities including antioxidant and antiinflammatory effects that could alleviate neurological and heart diseases, but its role in the prevention of cisplatin-induced hearing loss(CIHL) is not yet well understood. In our study, a steady interaction between AST and the E3 ligase adapter Kelch-like ECH-associated protein 1, a predominant repressor of nuclear factor erythroid 2-related factor 2(NRF2), was performed and tested via computer molecular docking and dynamics. AST protected against cisplatin-induced ototoxicity via NRF2 mediated pathwayusing quantitative PCR and Western blotting. The levels of reactive oxygen species(ROS) and mitochondrial membrane potential revealed that AST reduced ROS overexpression and mitochondrial ***, AST exerted anti-apoptosis effects in mouse cochlear explants using immunofluorescence staining and HEI-OC1 cell lines using quantitative PCR and Western blotting. Finally, AST combined with poloxamer was injected into the middle ear through the tympanum, and the protection against CIHL was evaluated using the acoustic brain stem test and immunofluorescent staining in adult mice. Our results suggest that AST reduced ROS overexpression, mitochondrial dysfunction, and apoptosis via NRF2-mediated pathway in cisplatin-exposed HEI-OC1 cell lines and mouse cochlear explants, finally promoting cell survival. Our study demonstrates that AST is a candidate therapeutic agent for CIHL.

关键词： Astaxanthine Cisplatin Hearing loss Mitochondrial Ototoxicity Reactive oxygen species Apoptosis

A study of gentamicin injury mechanisms using cultured mouse cochlear spiral ganglion cells

在线全文

学校读者我要写书评

暂无评论

Journal of Otology 2011年第1期6卷 31-35页

作者： gu xi LIN Chang ZHANG Rong Department of Otolaryngology-Head and Neck Surgery First Affiliated Hospital of Fujian Medical University Fuzhou Fujian 350005 China

Objective To study gentamicin injury mechanisms using postnatal mouse cochlear spiral gangcells （SGC）. Methods SGCs were isolated using a combinatorial approach of enzymatic digestion and mechanical separation from P2 - 6 Kunming mouse cochleae. After 4 days, cultured SGCs were fixed with 4% paraformaldehyde at room temperature for immunocytochemical examination using the methods of S-P and the monoclonal antibody against mouse neurofilament protein （Neurofilament-68/200Kda, NF-L＋ H）. SGCs were randomly divided into a blank control group and three gentamicin treatment groups （medium gentamicin concentration at 50 mg/L, 100 mg/L and 150 mg/L respectively）, SGCs were collected and examined under a transmission electron microscope after being cultured for 48 h. Results SGC primary culture was successful. SGC cytoplasm and neurites were dyed brownish yellow by the monoelonal mouse neurofilament protein antibody. SGCs showed classical bipolar neuron appearance. Under the transmission electron microscope,.gentamicin treated SGCs showed morphological features different compared to those in the blank control group, which might indicate apoptosis. Conclusion Our results indicate that gentamicin has direct toxic effects on cochlear SGCs in mice and the injury mechanism is closely related with apoptosis. Damage to mitochor, dria may play an important role in the process.

关键词： gentamicins spiral ganglion cells, cultured microscopy electron transmission apoptosis

Modular Assembly of Six-Membered Carbocyclic Spirooxindoles via Peterson Olefination/Michael Addition/C(sp^(3))Arylation Cascade

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第21期42卷 2614-2620页

作者： Feng-Cheng Jia Zi-Yi Yuan Na Luo Shuang-xi gu xiao-Qiang Hu School of Chemistry and Environmental Engineering School of Chemical Engineering and Pharmacyand Key Laboratory of Green Chemical ProcessMinistry of EducationWuhan Institute of TechnologyWuhanHubei430205 China Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education School of Chemistry and Materials ScienceSouth-Central University for NationalitiesWuhanHubei430074 China

Concise assembly of spirooxindoles is of great significance but a challenging task in modern organic *** herein is an unusual base-promoted[4+2]spiroannulation of rarely used isatin-derivedβ-silylcarbinols with o-halogen aromatic ketones,which enables rapid and modular synthesis of six-membered carbocyclic spirooxindoles in high yields with excellent functional group tolerance(>50 examples).Mechanistic experiments revealed that this reaction involved a Peterson olefination,Michael addition and intramolecular C(sp^(3))arylation *** variegated synthetic derivatization of target products and successful construction of bioactive molecules further illustrate the synthetic potential in spirooxindole-related drug discovery.

关键词： Cascade reaction Spirooxindole Peterson olefination C(sp^(3))arylation of oxindole Transition-metal-free

Optimization of the Production Organization Pattern in Tangshan Iron and Steel Co., Ltd.

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2014年第S1期21卷 17-22页

作者： Zong-xi gu An-jun XU Jin-bao CHANG Shuang-wu LI You-bing xiANG State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Metallurgy and Ecology Engineering University of Science and Technology Beijing Tangshan Iron and Steel Company of Hebei Iron and Steel Group

High-efficiency production organization should be simple and "laminar". A one to one "laminar flow" operation mechanism is supposed to be accepted as a prerequisite to build high-efficiency clean steel "production platform". Concerning the fact that establishing a one to one "laminar flow" production pattern is impossible at Tangshan Iron and Steel Co., Ltd., "quasi-laminar flow" production pattern was evaluated. Result shows that rolling bar products of various specifications have great impact on the liquid steel supply model between BOF and CC. Considering the process matching issue of steelmaking-continuous casting-rolling process in bar production line, a "quasi-laminar flow" production pattern between BOF and CC was proposed according to different rolling specification in bar mills. Through analysis and research on current production pattern, combined with principles and strategy for BOF workshop control, and taking the plant layout into account, "quasi-laminar flow" production pattern was finally established. Moreover, Gantt chart of "quasi-laminar flow" production pattern was drawn. It is shown that the relative "order degree" of the "quasi-laminar flow" production pattern rises, which is conductive to production scheduling and ladle operation turnaround in comparison with "turbulence" production pattern. While a careful evaluation should be conducted due to the fluctuant temperature drop caused by the inevitable inserted heats and decreased operation rate of inserted BOF before adapting the production pattern.

关键词： steelmaking-casting process matching between converters and continuous casters 'quasi-laminar flow' production pattern Gantt chart

GdCl₃ abates hepatic ischemia-reperfusion injury by inhibiting apoptosis in rats

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2009年第5期8卷 518-523页

作者： Jian-Yi Li xi gu Wen-Hai Zhang Shi Jia Yong Zhou Department of General Surgery Shengjing Hospital China Medical University Shenyang 110004 China.

BACKGROUND:Gadolinium chloride(GdCl3)is a specific inhibitor of Kupffer cells(KCs),which are important promoters of various liver *** is therefore of interest to explore the role of KCs in liver ischemia-reperfusion injury and their relations with apoptosis caused by ischemia-reperfusion injury. METHODS:One hundred male Wistar rats(190-210 g, 6-7 weeks old)were divided into two groups at random, GdCl3 group and control *** were collected at 0.5,1,6,12,and 24 hours from each group after *** alanine aminotransferase(ALT)and aspartate aminotransferase(AST)were measured by an automatic biochemical ***-αin serum was measured by enzyme-linked immunosorbent assay(ELISA). Malondialdehyde(MDA)in the liver mitochondria was measured by a colorimetric *** changes in the liver and immunohistochemical staining for caspase-3 were observed under an optical *** ratio of apoptotic cells was measured by TdT-mediated dUTP nick-end labeling(TUNEL),and ultrastructural features of apoptosis were observed with a transmission electron microscope(TEM). RESULTS:The levels of ALT in the GdCl3 group were lower than those in the control group after reperfusion for 0.5, 1,6 and 12 hours(P<0.05);and the levels of AST in the GdCl3 group were lower than those in the control group after reperfusion for 6 and 12 hours(P<0.05).The levels of TNF-αin the GdCl 3 group were lower than those in the control group after reperfusion for each time(P<0.05). The concentrations of MDA after reperfusion in the GdCl3 group were lower than those in the control group after reperfusion for 6,12 and 24 hours(P<0.05).After reperfusion for 0.5,1,6 and 12 hours,the integral optical density(IOD)of caspase-3-positive cells was lower in theGdCl3 group than in the control group(P<0.05).After reperfusion for 1,6,and 12 hours,the IOD of cells stained by TUNEL in the GdCl3 group was lower than that in the control group(P<0.05). CONCLUSIONS:GdCl3

关键词： gadolinium chloride Kupffer cell ischemia-reperfusion injury caspase-3 apoptosis