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Reversible solid-liquid conversion enabled by self-capture effect for stable non-flow zinc-bromine batteries 被引量:1
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作者 Xixi Zhang Xiaoke Wang +7 位作者 Guangmeng Qu Tairan Wang Xiliang Zhao Jun Fan Cuiping Han Xijin Xu Chunyi Zhi Hongfei Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第6期1035-1044,共10页
Non-flow aqueous zinc-bromine batteries without auxiliary components(e.g.,pumps,pipes,storage tanks)and ion-selective membranes represent a cost-effective and promising technology for large-scale energy storage.Unfort... Non-flow aqueous zinc-bromine batteries without auxiliary components(e.g.,pumps,pipes,storage tanks)and ion-selective membranes represent a cost-effective and promising technology for large-scale energy storage.Unfortunately,they generally suffer from serious diffusion and shuttle of polybromide(Br^(-),Br^(3-))due to the weak physical adsorption between soluble polybromide and host carbon materials,which results in low energy efficiency and poor cycling stability.Here,we develop a novel self-capture organic bromine material(1,10-bis[3-(trimethylammonio)propyl]-4,4'-bipyridinium bromine,NVBr4)to successfully realize reversible solid complexation of bromide components for stable non-flow zinc-bromine battery applications.The quaternary ammonium groups(NV^(4+)ions)can effectively capture the soluble polybromide species based on strong chemical interaction and realize reversible solid complexation confined within the porous electrodes,which transforms the conventional“liquid-liquid”conversion of soluble bromide components into“liquid-solid”model and effectively suppresses the shuttle effect.Thereby,the developed non-flow zinc-bromide battery provides an outstanding voltage platform at 1.7 V with a notable specific capacity of 325 mAh g^(-1)NVBr4(1 A g^(-1)),excellent rate capability(200 mAh g^(-1)NVBr4 at 20 A g^(-1)),outstanding energy density of 469.6 Wh kg^(-1)and super-stable cycle life(20,000 cycles with 100%Coulombic efficiency),which outperforms most of reported zinc-halogen batteries.Further mechanism analysis and DFT calculations demonstrate that the chemical interaction of quaternary ammonium groups and bromide species is the main reason for suppressing the shuttle effect.The developed strategy can be extended to other halogen batteries to obtain stable charge storage. 展开更多
关键词 Solid-liquid conversion Self-capture non-flow zinc-bromine batteries Quaternary ammonium
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N-acetylcysteine attenuates oxidative stress and liver pathology in rats with non-alcoholic steatohepatitis 被引量:2
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作者 Duangporn Thong-Ngam Suchittra Samuhasaneeto +1 位作者 Onanong Kulaputana Naruemon Klaikeaw 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第38期5127-5132,共6页
AIM: To evaluate attenuating properties of N-acetylcysteine (NAC) on oxidative stress and liver pathology in rats with non-alcoholic steatohepatitis (NASH). METHODS: Male Sprague-Dawley rats were randomly divided into... AIM: To evaluate attenuating properties of N-acetylcysteine (NAC) on oxidative stress and liver pathology in rats with non-alcoholic steatohepatitis (NASH). METHODS: Male Sprague-Dawley rats were randomly divided into three groups. Group 1 (control, n = 8) was free accessed to regular dry rat chow (RC) for 6 wk. Group 2 (NASH, n = 8) was fed with 100% fat diet for 6 wk. Group 3 (NASH + NAC20, n = 9) was fed with 100% fat diet plus 20 mg/kg per day of NAC orally for 6 wk. All rats were sacrificed to collect blood and liver samples at the end of the study. RESULTS: The levels of total glutathione (GSH) and hepatic malondialdehyde (MDA) were increased significantly in the NASH group as compared with the control group (GSH; 2066.7 ± 93.2 vs 1337.5 ± 31.5 μmol/L and MDA; 209.9± 43.9 vs 3.8 ±1.7 μmol/g protein, respectively, P < 0.05). Liver histopathology from group 2 showed moderate to severe macrovesicular steatosis, hepatocyte ballooning, and necroinflammation. NAC treatment improved the level of GSH (1394.8 ± 81.2 μmol/L, P < 0.05), it did not affect MDA (150.1 ± 27.0 μmol/g protein), but led to a decrease in fat deposition and necroinflammation. CONCLUSION: NAC treatment could attenuate oxidative stress and improve liver histology in rats with NASH. 展开更多
关键词 N-ACETYLCYSTEINE Oxidative stress non- alcoholic steatohepatitis
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Novel ternary metals-based telluride electrocatalyst with synergistic effects of high valence non-3d metal and oxophilic Te for pH-universal hydrogen evolution reaction 被引量:2
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作者 Seunghwan Jo Wenxiang Liu +5 位作者 Yanan Yue Ki Hoon Shin Keon Beom Lee Hyeonggeun Choi Bo Hou Jung Inn Sohn 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期736-743,I0015,共9页
Electrocatalyst designs based on oxophilic foreign atoms are considered a promising approach for developing efficient pH-universal hydrogen evolution reaction(HER)electrocatalysts by overcoming the sluggish alkaline H... Electrocatalyst designs based on oxophilic foreign atoms are considered a promising approach for developing efficient pH-universal hydrogen evolution reaction(HER)electrocatalysts by overcoming the sluggish alkaline HER kinetics.Here,we design ternary transition metals-based nickel telluride(Mo WNi Te)catalysts consisting of high valence non-3d Mo and W metals and oxophilic Te as a first demonstration of non-precious heterogeneous electrocatalysts following the bifunctional mechanism.The Mo WNi Te showed excellent HER catalytic performance with overpotentials of 72,125,and 182 mV to reach the current densities of 10,100,and 1000 mA cm^(-2),respectively,and the corresponding Tafel slope of 47,52,and 58 mV dec-1in alkaline media,which is much superior to commercial Pt/C.Additionally,the HER performance of Mo WNi Te is well maintained up to 3000 h at the current density of 100 mA cm^(-2).It is further demonstrated that the Mo WNi Te exhibits remarkable HER activities with an overpotential of 45 mV(31 mV)and Tafel slope of 60 mV dec-1(34 mV dec-1)at 10 mA cm^(-2)in neutral(acid)media.The superior HER performance of Mo WNi Te is attributed to the electronic structure modulation,inducing highly active low valence states by the incorporation of high valence non-3d transition metals.It is also attributed to the oxophilic effect of Te,accelerating water dissociation kinetics through a bifunctional catalytic mechanism in alkaline media.Density functional theory calculations further reveal that such synergistic effects lead to reduced free energy for an efficient water dissociation process,resulting in remarkable HER catalytic performances within universal pH environments. 展开更多
关键词 Telluride catalyst Oxophilic effect High valence non-3d metal Bifunctional mechanism pH-universal hydrogen evolution reaction
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Characteristics and risk of violation behavior of non-motorists at signalized intersections 被引量:6
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作者 赵星 任刚 +2 位作者 杜轩 王鹏 王卫杰 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期423-429,共7页
Aiming at prevalent violations of non-motorists at urban intersections in China, this paper intends to clarify the characteristics and risks of non-motorist violations at signalized intersections through questionnaire... Aiming at prevalent violations of non-motorists at urban intersections in China, this paper intends to clarify the characteristics and risks of non-motorist violations at signalized intersections through questionnaires and video recordings, which may serve as a basis for non-motorized vehicle management. It can help improve the traffic order and enhance the degree of safety at signalized intersections. To obtain the perception information, a questionaire survey on the Internet was conducted and 972 valid questionnaires were returned. It is found that academic degree contributes little to non-motorist violations, while electrical bicyclists have a relatively higher frequency of violations compared with bicyclists. The video data of 18 228 non-motorist behaviors indicate that the violation rate of all non-motorists is 26.5%; the number of conflicts reaches 1 938, among which violation conflicts account for 66.8%. The study shows that the violation rates and the violation behavior at three types of surveyed intersections are markedly different. It is also concluded that the conflict rates and the violation rates are positively correlated. Furthermore, signal violation, traveling in the wrong direction, and overspeeding to cross the intersection are the most dangerous among traffic violation behaviors. 展开更多
关键词 traffic violation behavior traffic safety non- motorist signal intersection
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Modified streptozotocin-induced diabetic model in rodents
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作者 Anton Lennikov Farris ElZaridi Menglu Yang 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第5期777-780,共4页
Streptozotocin(STZ)-induced type I diabetes mellitus(DM)models have been pivotal in diabetes research due to their ability to mimic the insulin-dependent hyperglyce-mia akin to human type I diabetes.However,these mode... Streptozotocin(STZ)-induced type I diabetes mellitus(DM)models have been pivotal in diabetes research due to their ability to mimic the insulin-dependent hyperglyce-mia akin to human type I diabetes.However,these models often suffer from poor induction rates and low survival post-STZ induction,especially in long-term experi-ments,necessitating insulin supplementation,which introduces additional variables to experiments.To address this,we present a novel modification to the STZ-induced DM model in C57BL/6J mice to improve survival rates without insulin supplemen-tation.Our method involves non-fasting,low-dose STZ injections dissolved in pH-neutral phosphate buffer saline instead of acidic sodium citrate buffer,administered over 5 days.We observed hyperglycemia induction in 94.28%of mice within a week post-injection,with stable high blood glucose levels,stable body weight,and minimal mortality up to 21 weeks.Notably,omitting 10%sucrose in water and fasting did not affect hyperglycemia induction.Our findings suggest that the modified protocol not only decreases the experimental effort of the researchers,but reduces animal stress and mortality,thus enhancing experimental outcomes and animal welfare.By opti-mizing the STZ-induced DM model in C57BL/6J mice,our study provides a valuable resource for researchers aiming to study diabetes and its complications while mini-mizing experimental variability and animal usage. 展开更多
关键词 HYPERGLYCEMIA non- FASTING STREPTOZOTOCIN Type 1 diabetes mellitus
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Alkylpolyglycoside inducing poly (butylene terephthalate) non-woven graft copolymerization of chitosan
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作者 陈叶廷 施婷婷 +4 位作者 祁姗姗 杨牧 孟娜 龚祝南 黄斌 《Journal of Southeast University(English Edition)》 EI CAS 2012年第4期474-479,共6页
In order to improve the wettability and biocompatibility of the poly (butylene terephthalate) non-woven (PBTNW), the method of surface modification is used to graft copolymerization of chitosan (CS) onto the PBT... In order to improve the wettability and biocompatibility of the poly (butylene terephthalate) non-woven (PBTNW), the method of surface modification is used to graft copolymerization of chitosan (CS) onto the PBTNW under alkylpolyglycoside (APG) inducing. The product is thoroughly characterized with the Fourier transform infrared spectroscopy (FrIR), the electron spectroscopy for chemical analysis (ESCA), the thermogravimetric (TG) and the scanning electron microscopy (SEM). It is found that chitosan is successfully grafted onto PBTNW. In addition, the water contact angles, hemolysis tests and cytotoxicity evaluation tests show an improvement in wettability and biocompatihility as a result of graft copolymerization of chitosan. So the CS-grafted PBTNW exhibits greater superiority than the original PBTNW. The CS-grafted PBTNW can be a candidate for blood filter materials and other medical applications. 展开更多
关键词 CHITOSAN GRAFT poly (butylene terephthalate) non- woven alkylpolyglycoside BIOCOMPATIBILITY WETTABILITY
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Use of non-selective beta blockers in cirrhosis:The evidence we need before closing(or not) the window 被引量:4
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作者 Vincenzo La Mura Giulia Tosetti +1 位作者 Massimo Primignani Francesco Salerno 《World Journal of Gastroenterology》 SCIE CAS 2015年第8期2265-2268,共4页
Non selective beta blockers(NSBBs)are used in primary and secondary prophylaxis of portal hypertensionrelated bleeding in patients with cirrhosis.The efficacy of NSBBs treatment is predicted by hemodynamic response in... Non selective beta blockers(NSBBs)are used in primary and secondary prophylaxis of portal hypertensionrelated bleeding in patients with cirrhosis.The efficacy of NSBBs treatment is predicted by hemodynamic response in term of reduction of the hepatic venouspressure gradient(HVPG)below 12 mm Hg or at least20%of the basal value.Nevertheless a relevant number of patients who do not achieve this HVPG reduction during NSBBs therapy do not bleed during follow up;this evidence suggests an additional non-hemodynamic advantage of NSBBs treatment to modify the natural history of cirrhosis.Recent studies have questioned the efficacy and safety of NSBBs in patients with advanced stage of liver disease characterized by refractory ascites and/or spontaneous bacterial peritonitis.These studies have suggested the existence of a defined and limited period to modify the natural history of cirrhosis by NSBBs:the"window hypothesis".According with this hypothesis,patients with cirrhosis benefit from the use of NSBBs from the appearance of varices up to the development of an advanced stage of cirrhosis.Indeed,in patients with refractory ascites and/or spontaneous bacterial peritonitis the hemodynamic effects of NSBBs may expose to a high risk of further complications such as renal insufficiency and/or death.Methodological concerns and contrasting results counterbalance the evidence produced up to now on this issue and are the main topic of this editorial. 展开更多
关键词 BLEEDING PROPHYLAXIS End stage liver disease non-s
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Optimal Design of Multiple Stress Constant Accelerated Life Test Plan on Non-rectangle Test Region 被引量:8
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作者 CHEN Wenhua GAO Liang +2 位作者 LIU Juan QIAN Ping PAN Jun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第6期1231-1237,共7页
For optimal design of constant stress accelerated life test(CSALT) with two-stress, if the stresses could not reach the highest levels simultaneously, the test region becomes non-rectangular. For optimal CSALT desig... For optimal design of constant stress accelerated life test(CSALT) with two-stress, if the stresses could not reach the highest levels simultaneously, the test region becomes non-rectangular. For optimal CSALT design on non-rectangle test region, the present method is only focused on non-rectangle test region with simple boundary, and the optimization algorithm is based on experience which can not ensure to obtain the optimal plan. In this paper, considering the linear-extreme value model and the optimization goal to minimize the variance of lifetime estimate under normal stress, the optimal design method of two-stress type-I censored CSALT plan on general non-rectangular test region is proposed. First, two properties of optimal test plans are proved and the relationship of all the optimal test plans is determined analytically. Then, on the basis of the two properties, the optimal problem is simplified and the optimal design method of two-stress CSALT plan on general non-rectangular test region is proposed. Finally, a numerical example is used to illustrate the feasibility and effectiveness of the method, The result shows that the proposed method could obtain the optimal test plan on non-rectangular test regions with arbitrary boundaries. This research provides the theory and method for two-stress optimal CSALT planning on non-rectangular test regions. 展开更多
关键词 accelerated life test non- rectangular test region test plan optimal design
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Moxifloxacin-containing triple therapy after non-bismuth quadruple therapy failure for Helicobacter pylori infection 被引量:2
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作者 Ji Hyun Lim Dong Ho Lee +4 位作者 Seong Tae Lee Nayoung Kim Young Soo Park Cheol Min Shin In Sung Song 《World Journal of Gastroenterology》 SCIE CAS 2015年第46期13124-13131,共8页
AIM: To assess the efficacy of moxifloxacin-containing triple therapy after non-bismuth quadruple therapy failure for Helicobacter pylori(H. pylori) eradication.METHODS: Between January 2010 and December 2012,we scree... AIM: To assess the efficacy of moxifloxacin-containing triple therapy after non-bismuth quadruple therapy failure for Helicobacter pylori(H. pylori) eradication.METHODS: Between January 2010 and December 2012,we screened individuals who were prescribed non-bismuth quadruple therapy for H. pylori eradication. Among them,a total of 98 patients who failed non-bismuth quadruple therapy received 1-wk or 2-wk moxifloxacin-containing triple therapy(400 mg moxifloxacin once daily,and 20 mg of rabeprazole and 1 g of amoxicillin twice daily). H. pylori status was evaluated using the 13C-urea breath test 4 wk later,after treatment completion. The eradication rates were determined by intention-to-treat and per-protocol analyses.RESULTS: In total,60 and 38 patients received 1-wk and 2-wk moxifloxacin-containing triple therapy,respectively. The intention-to-treat and per-protocol eradication rates were 56.7%(95%CI: 45.0-70.0) and 59.6%(95%CI: 46.6-71.7) in the 1-wk group and 76.3%(95%CI: 63.2-89.5) and 80.6%(95%CI: 66.7-91.9) in the 2-wk group(P = 0.048 and 0.036,respectively). All groups had good compliance(95% vs 94.9%). Neither group showed serious adverse events,and the proportions of patients experiencing mild side effects were not significantly different(21.1% vs 13.9%). Clinical factors such as age,sex,alcohol and smoking habits,comorbidities,and presence of gastric or duodenal ulcer did not influence the eradication therapy efficacy. The efficacy of second-line eradication therapy did not differ significantly according to the firstline regimen.CONCLUSION: Two-week moxifloxacin-containing triple therapy showed better efficacy than a 1-wk regimen after non-bismuth quadruple therapy failure.Key words: Helicobacter pylori; Moxifloxacin-based triple; Non-bismuth quadruple; Second-line; 展开更多
关键词 HELICOBACTER PYLORI Moxifloxacin-based triple non-
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Non-3GPP对EPS的安全接入研究 被引量:1
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作者 杜雪涛 袁捷 +1 位作者 吴晓岩 张振涛 《电信工程技术与标准化》 2009年第7期11-15,共5页
Non-3GPP网络安全接入EPS是未来异构网络融合的重要基础。本文介绍了Non-3GPP网络接入时EPS系统的安全架构、可信的Non-3GPP网络接入EPS系统的认证机制、密钥协商流程等。
关键词 安全接入 non-3GPP EPS认证密钥协商
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Tunnelling effect of the non-stationary Kerr black hole 被引量:1
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作者 杨树政 陈德友 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期817-821,共5页
Extending Parikh and Wilczek's work to the non-stationary black hole, we study the Hawking radiation of the non-stationary Kerr black hole by the Hamilto-Jacobi method. The result shows that the radiation spectrum is... Extending Parikh and Wilczek's work to the non-stationary black hole, we study the Hawking radiation of the non-stationary Kerr black hole by the Hamilto-Jacobi method. The result shows that the radiation spectrum is not purely thermal and the tunnelling probability is related to the change of Bekenstein Hawking entropy, which gives a correction to the Hawking thermal radiation of the black hole. 展开更多
关键词 Hamilton-Jacobi equation radiation spectrum self-gravitation interaction non- stationary Kerr black hole
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Non-Markovian dynamics of a qubit in a reservoir: different solutions of non-Markovian master equation 被引量:1
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作者 丁邦福 王小云 +2 位作者 唐艳芳 米贤武 赵鹤平 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第6期25-29,共5页
We present a non-Markovian master equation for a qubit interacting with a general reservoir, which is derived according to the Nakajima-Zwanzig and the time convolutionless projection operator technique. The non-Marko... We present a non-Markovian master equation for a qubit interacting with a general reservoir, which is derived according to the Nakajima-Zwanzig and the time convolutionless projection operator technique. The non-Markovian solutions and Markovian solution of dynamical decay of a qubit are compared. The results indicate the validity of non-Markovian approach in different coupling regimes and also show that the Markovian master equation may not precisely describe the dynamics of an open quantum system in some situation. The non-Markovian solutions may be effective for many qubits independently interacting with the heated reservoirs. 展开更多
关键词 Nakajima-Zwanzig and time convolutionless projection operator technique non- Markovian solutions Markovian solutions correlation function QUBIT
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PURGING OF ACUTE NON-LYMPHOCYTIC LEUKEMIA PROGENITORS BY PROCAINE AND HYPERTHERMIA
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作者 荣跃 夏学鸣 林宝爵 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1993年第1期73-76,共4页
Procaine and hyperthermia have been shown to possess a relatively selective cytotoxicity to leukemlc cells. In this study, the combined effects of procaine and hyperthermia on the growth of hematopoietic progenitors (... Procaine and hyperthermia have been shown to possess a relatively selective cytotoxicity to leukemlc cells. In this study, the combined effects of procaine and hyperthermia on the growth of hematopoietic progenitors (GM-CFU) and ieukemic progenitors (L-CFU) were examined to determine if this combination resulted in a great selective killing of leukemlc cells than that achieved by procaine or heat alone. When the cells were treated simutaneously with procaine (2 mM) and hyperthermia (42℃) for one hour, the killing of L-CFU was enhanced considerably whereas GM-CFU were not markedly affected. These data Indicate that the combined treatment with procain and hyperthermia might offer an efficient mean to selectively purge residual leukemlc cells in vitro. Procaine with hyperthermia may have a role in clinical autoiogous bone marrow transplantation for acute leukemia. 展开更多
关键词 PROCAINE Hyperthermies Acute non- lymphocytic leukemia Purge.
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Non-Cooperative Differential Game Based Load Balancing Algorithm in Radio-Over-Fibre System
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作者 HE Zhen WANG Jianping 《China Communications》 SCIE CSCD 2014年第A02期79-85,共7页
Load balancing plays a critical role in a cellular network. As one kind of cellular network, Radio-over-Fibre (RoF) system can provide ubiquitous high data-rate transmissions, which has attracted many attentions, bu... Load balancing plays a critical role in a cellular network. As one kind of cellular network, Radio-over-Fibre (RoF) system can provide ubiquitous high data-rate transmissions, which has attracted many attentions, but it also suffer load unbalancing problem. In order to improve the system performance, in this paper, we propose a novel loading balance scheme in RoF system based on differential game theory. The scheme formulates the load allocated to each RAP (Radio Access Point) as a Nasb Equilibrium, using non-cooperative differential game to obtain the optical load allocation of each RAP. The simulations performed show that the non-cooperative differential game algorithm is applicable and the optimal load solution can be achieved. 展开更多
关键词 loading balancing ROF RAP non- cooperative differential game
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A NONLINEAR DEGENERATE PARABOLIC EQUATION WITH NON-LOCAL SOURCE
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作者 Deng Weibing Xie ChunhongDept.ofMath.,NanjingUniv.,Nanjing210093,China. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第2期171-176,共6页
The global existence and finite time blow up of the positive solution for a nonlinear degenerate parabolic equation with non- local source are studied
关键词 global existence blow up degenerate parabolic equation non- local source
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Robust Iterative Learning Controller for the Non-zero Initial Error Problem on Robot Manipulator
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作者 TAO Li-li 1,YANG Fu-wen 2 (1. Department of Automation, University of Xiamen, Xiamen 361005, Chi na 2. Department of Electrical Engineering, University of Fuzhou, Fuzhou 350002, C hina) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期-,共2页
Industrial robot system is a kind of dynamic system w ith strong nonlinear coupling and high position precision. A lot of control ways , such as nonlinear feedbackdecomposition motion and adaptive control and so o n, ... Industrial robot system is a kind of dynamic system w ith strong nonlinear coupling and high position precision. A lot of control ways , such as nonlinear feedbackdecomposition motion and adaptive control and so o n, have been used to control this kind of system, but there are some deficiencie s in those methods: some need accurate and some need complicated operation and e tc. In recent years, in need of controlling the industrial robots, aiming at com pletely tracking the ideal input for the controlled subject with repetitive character, a new research area, ILC (iterative learning control), has been devel oped in the control technology and theory. The iterative learning control method can make the controlled subject operate as desired in a definite time span, merely making use of the prior control experie nce of the system and searching for the desired control signal according to the practical and desired output signal. The process of searching is equal to that o f learning, during which we only need to measure the output signal to amend the control signal, not like the adaptive control strategy, which on line assesses t he complex parameters of the system. Besides, since the iterative learning contr ol relies little on the prior message of the subject, it has been well used in a lot of areas, especially the dynamic systems with strong non-linear coupling a nd high repetitive position precision and the control system with batch producti on. Since robot manipulator has the above-mentioned character, ILC can be very well used in robot manipulator. In the ILC, since the operation always begins with a certain initial state, init ial condition has been required in almost all convergence verification. Therefor e, in designing the controller, the initial state has to be restricted with some condition to guarantee the convergence of the algorithm. The settle of initial condition problem has long been pursued in the ILC. There are commonly two kinds of initial condition problems: one is zero initial error problem, another is non-zero initial error problem. In practice, the repe titive operation will invariably produce excursion of the iterative initial stat e from the desired initial state. As a result, the research on the second in itial problem has more practical meaning. In this paper, for the non-zero initial error problem, one novel robust ILC alg orithms, respectively combining PD type iterative learning control algorithm wit h the robust feedback control algorithm, has been presented. This novel robust ILC algorithm contain two parts: feedforward ILC algorithm and robust feedback algorithm, which can be used to restrain disturbance from param eter variation, mechanical nonlinearities and unmodeled dynamics and to achieve good performance as well. The feedforward ILC algorithm can be used to improve the tracking error and perf ormance of the system through iteratively learning from the previous operation, thus performing the tracking task very fast. The robust feedback algorithm could mainly be applied to make the real output of the system not deviate too much fr om the desired tracking trajectory, and guarantee the system’s robustness w hen there are exterior noises and variations of the system parameter. In this paper, in order to analyze the convergence of the algorithm, Lyapunov st ability theory has been used through properly selecting the Lyapunov function. T he result of the verification shows the feasibility of the novel robust iterativ e learning control in theory. Finally, aiming at the two-freedom rate robot, simulation has been made with th e MATLAB software. Furthermore, two groups of parameters are selected to validat e the robustness of the algorithm. 展开更多
关键词 robust control iterative learning control non- zero initial error robot manipulator
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ON A DIFFERENTIAL EQUATION FOR KINETICS OF NON- ISOTHERMAL CRYSTALLIZATION
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作者 张志英 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1993年第2期125-132,共8页
A new differential equation was derived from the modified first-order kinetic model to describe the polymer crystallization processes. The crystallization experiments were carried out by means of DSC. Poly (ethylene t... A new differential equation was derived from the modified first-order kinetic model to describe the polymer crystallization processes. The crystallization experiments were carried out by means of DSC. Poly (ethylene terephthalate) resins were selected as the samples containing different catalysts. The relationships between the parameters obtained from the known Avrami equation and from one in the present paper were discussed. A method for applying the equation to determine the kinetic parameters from a constant heating and a constant cooling curve was proposed. 展开更多
关键词 non- isothermal crystallization Crystallization kinetics POLYMER Differential scanning calorimetry (DSC).
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^(18)F-FETNIM PET/CT hypoxia imaging in non-small cell lung cancer:preliminary clinical observation
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作者 Ling Li Man Hu +4 位作者 Wei Zhao Jinbo Yue Guoren Yang Shuqiang Zhao Jinming Yu 《The Chinese-German Journal of Clinical Oncology》 CAS 2010年第6期330-333,共4页
Objective:The aims of this study were to evaluate potential side effects of 18F-fluoroerythronitroimidazole (18F-FETNIM) as a new-type hypoxia-imaging agent and to investigate the feasibility of 18F-FETNIM PET imaging... Objective:The aims of this study were to evaluate potential side effects of 18F-fluoroerythronitroimidazole (18F-FETNIM) as a new-type hypoxia-imaging agent and to investigate the feasibility of 18F-FETNIM PET imaging in advanced non-small cell lung cancer (NSCLC) patients and the correlations of hypoxia extent with tumor volume or pathological type. Methods: Twenty-six NSCLC patients were prospectively included in the study. PET/CT scans were performed 2 h after intravenous injection of 18F-FETNIM in all 26 patients. A pixel-by-pixel calculation of tumor to blood (T/B) activity ratio for all image planes was calculated. The number of pixels in the tumor volume with a T/B ratio≥ 1.5,indicating significant hypoxia,was determined and converted to mL units to measure the hypoxia volume (HV). Results: The images were clearly identified after 2 h post-injection of 18F-FETNIM. The tumors in 4 cases were not distinguished from background,while the remaining 22 displayed local 18F-FETNIM uptake in thoracic lesions moderately to markedly higher than background. There was no correlation between 18F-FETNIM uptake with pathological type. There were significant correlations of HV and also the T/B ratio with tumor volume. Conclusion:18F-FETNIM is a promising hypoxia-imaging agent which clinical use is safe and satisfactory. The preliminary study provides valuable methods and experience to its further research. 展开更多
关键词 ^18F-fluoroerythronitroimidazole (^18F-FETNIM) HYPOXIA imaging positron emission tomography (PET) non- small cell lung cancer (NSCLC)
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Geochemical Stratigraphy and Microvertebrate Assemblage Sequences across the Silurian/Devonian Transition in South China 被引量:11
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作者 ZHAO Wenjin WANG Nianzhong +3 位作者 ZHU Min Ulrich MANN Ulrich HERTEN Andreas LǖKE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第2期340-353,共14页
Carbon isotope (δ13Corg) analyses of non-marine clastic rocks and neritic carbonates and black shales spanning the Silurian/Devonian transition are compared from two richly fossiliferous sequences in Qujing of East... Carbon isotope (δ13Corg) analyses of non-marine clastic rocks and neritic carbonates and black shales spanning the Silurian/Devonian transition are compared from two richly fossiliferous sequences in Qujing of East Yunnan and Zoige of Sichuan, South China. The two sections, Xishancun and Putonggou sections in South China, reveal positive δ13Corg shifts happening in the Upper Pridoli and Lower Devonian and reaching peak values as heavy as -25.2‰ (Xishancun) and -19.9‰(Putonggou) in the lowermost Lochkovian following the first occurrence of the thelodont Parathelodus and the conodont Icriodus woschmidti woschmidti (only in Putonggou Section and together with Protathyris-Lanceomyonia brachiopod fauna). These results replicate a globally known positive shift in δ13Corg from the uppermost Silurian to the lowermost Devonian. The δ13Corg variations across the Silurian/Devonian Boundary (SDB) at the two sections in South China exhibit a shift in carbon isotopic composition similar to the detailed SDB curves from the borehole Klonk-1 drilled at top of the Klonk Global Standard Stratotype-Section and Point (GSSP) in the Prague Basin, Czech Republic. In addition, four microvertebrate assemblages, including the Liaojiaoshan, Xishancun, Yanglugou and Xiaputonggou assemblages, are recognized from the Silurian/Devonian transition exposed in the Xishancun and Putonggou sections, respectively. The results from both carbon isotope stratigraphy and microvertebrate assemblage sequences suggest that the SDB in South China is located at the base of the Xishancun Formation (between sample QX-20 and sample QX-21) in the Xishancun Section and the lower part of the Xiaputonggou Formation (between sample ZP-09 and sample ZP-10) in the Putonggou Section. The isotopic trend for organic carbon together with the changes of microvertebrate remains across the SDB can offer an approach to a potential correlation of the SDB from different sedimentary facies, which help to correlate the marine with non-marine deposits. 展开更多
关键词 Carbon isotope stratigraphy microvertebrate assemblages Silurian-Devonian Boundary marine and non- marine stratigraphic correlation South China
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Continental- Margin Structure of Northeast China and Its Adjacent Areas 被引量:11
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作者 Tang Kedong, Shenyang Institute of Geology and Mineral Resources, Shenyang,Liaoning ProvinceWang Ying,Bureau of Geology and Mineral Resources of Heilongjiang Province,Harbin, HeilingjiangHe Guoqi and Shao Ji’an Peking U niversity, Beijing Liu Xinzhu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1995年第3期241-258,共18页
The continental margin of Northeast China and its adjacent areas is composed of two tectonic belts. The inner belt is a collage made up of fragments resulting from breakup of an old land with the north part related to... The continental margin of Northeast China and its adjacent areas is composed of two tectonic belts. The inner belt is a collage made up of fragments resulting from breakup of an old land with the north part related to the evolution of the Palaeo-Asian Ocean and the south part to the evolution of the Palaeo - Pacific Ocean. The outer belt is a Mesozoic terrane, which is a melange made up of fragments of the Late Palaeozoic to Early Mesozoic oceanic crust and the Late M esozoic trench accumulations.There existed another ocean-the Palaeo - Pacific Ocean during the period from the closing of the Palaeo-Asian Ocean to the opening of the modern Pacific Ocean or from the Devonian to Jurassic, and the ocean-floor spreading of the Palaeo - Pacific Ocean led to the formation of the above-mentioned tectonic belts. The development of the strike-slip fault system after the Late Jurassic and the formation of an epicontinental volcano -plutonic rock belt in the Late Cretaceous to Early Tertiary are attributed to the interaction between the modern Pacific plate and the Eurasian plate. 展开更多
关键词 continental-margin structure Bohai Sea block Mesozoic terrane non- subducted ocean crust Palaeo - Pacific Ocean
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