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Estimation for nearly unit root processes with GARCH errors

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Applied Mathematics(A Journal of Chinese Universities) 2010年第3期25卷 297-306页

作者： yuan yu-ze zhang Rong-mao Department of Mathematics, Zhejiang University, Hangzhou 310027, China Department of Mathematics Zhejiang University Hangzhou China

In this paper the limiting distribution of the least square estimate for the autoregressive coefficient of a nearly unit root model with GARCH errors is derived. Since the limiting distribution depends on the unknown variance of the errors, an empirical likelihood ratio statistic is proposed from which confidence intervals can be constructed for the nearly unit root model without knowing the variance. To gain an intuitive sense for the empirical likelihood ratio, a small simulation for the asymptotic distribution is given.

关键词： Nearly unit root GARCH error least square estimation Ornstein-Uhlenbeck process empirical likelihood.

Effect of Microstructure on Corrosion Fatigue Behavior of 1500 MPa Level Carbide-Free Bainite/Martensite Dual-Phase High Strength Steel

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Journal of Iron and Steel Research International 2011年第4期18卷 63-67页

作者： XU Lei WEI Dong-yuan yu Yang zhang Han BAI Bing-zhe Laboratory of Advanced Materials Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

Influence of microstructure of the experimental steels on the corrosion fatigue behavior in 3.5% of NaCl aqueous solution was *** results show that compared with the full martensite（FM）steel,the carbide-free bainite/martensite（CFB/M）steel has higher corrosion fatigue strength and corrosion fatigue crack threshold（ΔKthcf）,and lower corrosion crack propagation rate [（da/dN）cf].

关键词： high strength steel carbide-free bainite/martensite dual-phase steel corrosion fatigue

Evaluation of computed tomography obstruction index in guiding therapeutic decisions and monitoring percutanous catheter fragmentation in massive pulmonary embolism

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The Journal of Biomedical Research 2011年第6期25卷 431-437页

作者： Tongfu yu Mei yuan Qingbo zhang Haibing Shi Dehang Wang Department of Radiology the First Affiliated Hospital of Nanjing Medical University Nanjing Jiangsu 210029 China.

In the present study, we evaluated computed tomography pulmonary angiography （CTPA） in guiding therapeutic decisions and monitoring patients undergoing percutaneous catheter fragmentation in acute massive pulmonary embolism. From Jan 2003 to Dec 2009, 35 patients were diagnosed with acute massive pulmonary embolism by CTPA （TO） and treated with percutaneous catheter fragmentation. The severity was assessed by CT obstruction index （Qanadli index） and compared with Miller index. CTPA, oxygen saturation （SaO2） and pulmonary artery pressure were performed as follow-up index. The mean percentage of Qanadli index was （55 ± 13）% （range, 40%- 75%）, and Miller index was （62 ± 15）% （range, 45%-85%）. Correlations between them were statistically significant （r = 0.867, P 〈 0.0001）. The Qanadli index showed significant reduction [TO：（55±13）%; TI：（12±10）%; P 〈 0.001] in 33 patients. Significant correlation was observed between the Qanadli index, SaO2 （r = 0.934）, and pulmonary artery pressure （r = 0.813）. The Qanadli index provides an accurate method for distinguishing massive pulmonary embolism from sub-massive pulmonary embolism. It can be used to determine therapeutic options and monitor clinical outcomes.

关键词： pulmonary embolism CT angiography scoring system catheter fragmentation

Co/Co_(7)Fe_(3)heterostructures with controllable alloying degree on carbon spheres as bifunctional electrocatalyst forrechargeable zinc-air batteries

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 476-487页

作者： Junkang Chen Yongyue Zhuang Yanxin Qiao yu zhang Aihua yuan Hu Zhou School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Exploring efficient and nonprecious metal electrocatalysts of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is crucial for developing rechargeable zinc-air batteries(ZABs).Herein,an alloying-degree control strategy was employed to fabricate nitrogen-doped carbon sphere(NCS)decorated with dual-phase Co/Co_(7)Fe_(3)heterojunctions(CoFe@NCS).The phase composition of materials has been adjusted by controlling the alloying *** optimal CoFe_(0.08)@NCS electrocatalyst displays a half-wave potential of 0.80 V for ORR and an overpotential of 283 mV at 10 mA·cm^(-2)for OER in an alkaline *** intriguing bifunctional electrocatalytic activity and durability is attributed to the hierarchically porous structure and interfacial electron coupling of highly-active Co_(7)Fe_(3)alloy and metallic Co *** the CoFe_(0.08)@NCS material is used as air-cathode catalyst of rechargeable liquid-state zinc-air battery(ZAB),the device shows a high peak power-density(157 mW·cm^(-2))and maintains a stable voltage gap over 150 h,outperforming those of the benchmark(Pt/C+RuO_(2))-based *** particular,the as-fabricated solid-state flexible ZAB delivers a reliable compatibility under different bending *** work provides a promising strategy to develop metal/alloy-based electrocatalysts for the application in renewable energy conversion technologies.

关键词： bifunctional electrocatalysts oxygen reduction reaction oxygen evolution reaction zinc-air battery metal/alloy carbon sphere

Effects of Different Types of Chinese Fir Stands on Nu－trient Status of Soils

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Pedosphere 1995年第1期5卷 45-55页

作者： yu yuan-CHUN and zhang HUAN-CHAO(Nanjing Forestry University, Nanjing 210037 ( China))

The effects of different types of Chinese fir stand, including those with various composition (pure andmixed), in various cropping systems (first and continuous cropping system) and at different ages, on thenutrient status of soils in the hilly regions of southern Anhui Province were studied by means of ecologicalsequential comparison on the basis of similar climate and soil type. The work was carried out in the XiaoxiForest Farm of Jingxian County and the Caijiaqiao Forest Farm of Jingde County, where the soil is parayellowsoil derived from phyllite and sandstone. The results revealed that with the increase of age, Chinese fir purestand could accumulate organic matter and nitrogen in the soil but it resulted in decreasing of soil PH and baseions (especially Ca￣(2+)) compared to its mixed stand with broad-leaf trees such as Chinese sassafra.s. In orderto improve the soil fertility, it would be better to mix Chinese fir with broad-leaf trees when *** the management of Chinese fir pure stand, base compounds and phosphates should be added to the soilfor maintaining soil fertility and raising forest productivity.

关键词： broad-leaf tree Chinese fir mixed stand soil nutrient status

Endovenous laser ablation of great saphenous vein with ultrasound-guided perivenous tumescence： early and midterm results

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Chinese Medical Journal 2013年第3期126卷 421-425页

作者： CHEN Jia-quan XIE Hui DENG Hao-yu yuan Kai zhang Ji-wei zhang Hao zhang Lan Department of Vascular Surgery Renji Hospital School of Medicine Shanghai Jiao Tong University Shanghai 200127 China

Background Endovenous laser ablation （EVLA） is an improved method to treat varicose great saphenous veins （GSV） with a high satisfactory rate. This study aimed to evaluate the efficiency and safety of treatment by EVLA procedures with ultrasound-guided perivenous tumescence. Methods Thirty-one patients （31 limbs） with symptomatic varicose vein primary to chronic venous insufficiency （CVI） treated with EVLA were prospectively studied. The entire procedure was performed under ultrasound-guided tumescent local anesthesia. The patients were evaluated with a 18 month follow-up postoperation using clinical examination and venous duplex ultrasonography. Pain scores and quality of life （QOL） were recorded using visual analog scale （VAS） and the chronic venous insufficiency questionnaire （CIVIQ） at 1 week, 1 month, and 12 months after operation. Results All patients tolerated EVLA procedure well. The overall success occlusion rates of GSV were 92%, 94%, and 94% at 1, 12, and 18 months follow-up, respectively. The score of CIVIQ one week preoperation was 69.14±11.44 while that of CIVIQ one month postoperation was 85.32±4.89. The life quality has significantly improved after the operation of EVLA （t=12.71, P 〈0.05）. The VAS one month after treatment was lower than 1 week before therapy （t=8.048, P 〈0.05）. Major complications such as deep vein thrombosis and skin burns were not found. Most of the complications were minor and improved quickly. Conclusions This refinement type of EVLA procedure is a safe and effective treatment with a high satisfaction rate; it displayed noteworthy features including shortening hospitalization, early ambulant activity, and preferable occlusion rates.

关键词： endovenous laser ablation great saphenous vein occlusion tumescent anaesthesia

Role of aerolysin-type pore-formingproteinsin antimicrobial immunity of zebrafish

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Role of aerolysin-type pore-formingproteinsin antimicrobial ...

耐候透明性MBS/PVC增韧体系力学和加工性能

第12届生物毒素研究及医药应用学术大会

作者： yu-yuan zhang Yang Xiang yun zhang Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences & yunnan Province Kunming Institute of ZoologyCAS

The pore-forming toxin family members aerolysins are produced by many infectious bacteria types apart from Aeromonas,and they are important virulence factors for many types of *** interesting is that aerolysin-like proteins(ALPs) widely exist in various species from fungi,plants and animals,including wheat,grapes,fishes and birds,which are non-toxic species quite familiar to *** problem puzzling us is that why theses species hold proteins similar to bacteria virulence *** a previous study,we found that an ALP from frog Bombina maxima,namelyβγ-CAT(Bm-ALP1 plus Bm-TFF3) can be up-regulated and consequently initiate and potentiate host immune responses when facing bacteria ***,as a non-model species,it is very hard to make genetic manipulation of knock-in or knock-out of ALPs in frog ***,zebrafish was selected for further studies to illustrate in detail the physiological function of host-derived *** zebrafish was infected by bacteria Pseudomonas aeruginosa,the expression level of 10 genes of zebrafish ALPs were changed,with 5 of them up-regulated(wu:fb11f10,wu:fa92h10,zgc:172244,loc797839,loc794319) and 5 of them down-regulated(zgc:174689,zgc:172290,zgc:172260,loc564481,loc564660).The modulation of ALPs in zebrafish ZF-4 cells stimulated with LPS was analyzed as *** level of 5 genes was up-regulated(wu:fb11f10,loc797839,loc794319,zgc:172143,zgc:172244) and 2 was down-regulated(zgc:172290,wu:fa92h10).LPS stimulated the augmentation of ALPs in zebrafish derived ZF4 cells in a dose-dependent *** genes(zgc:172244,zgc:172290) were selected to construct the knock-out vector based onCRISPR-Cas9 system using plasmid *** PCR analysis of ZF4 cells transfected with the constructed knock-out vector revealed that mutagenesis rates reached 300%.Cas9 mRNA and gRNA are also being preparing to inject zebrafish embryos to acquire adult knock-out zebrafishes for further physiological *** results showed th

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塑料工业 2009年第3期37卷 63-66页

作者：李青于元章山东理工大学山东淄博255091

在甲基丙烯酸甲酯-丁二烯-苯乙烯三元接枝共聚物(MBS)合成中加入耐候性单体取代部分丁二烯得到耐候透明MBS树脂,研究了耐候透明性MBS/PVC增韧体系的力学性能、流变行为、透明性和材料的热性能。结果表明,自制的耐候透明性MBS树脂是综合... 详细信息

在甲基丙烯酸甲酯-丁二烯-苯乙烯三元接枝共聚物(MBS)合成中加入耐候性单体取代部分丁二烯得到耐候透明MBS树脂,研究了耐候透明性MBS/PVC增韧体系的力学性能、流变行为、透明性和材料的热性能。结果表明,自制的耐候透明性MBS树脂是综合性能优良的抗冲击改性剂,可用于制备耐候性PVC制品。

关键词：甲基丙烯酸甲酯-丁二烯-苯乙烯三元接枝共聚物聚氯乙烯力学性能透明性

The affect and importance of the Lichens in the Arid zone conservation and protection of water resource

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新疆大学学报（自然科学版） 2004年第Z1期21卷 16-19页

作者： WANG yu-liang zhang yuan-ming Adil Abdulla Anwar Tumur Abdulla Abbas Biology Department of Anhui Technical Teachers College Anhui Fengyang 233100 Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 College of the Life Science and Technology Xinjiang UniversityUrumqi830046 Biology Department of Anhui Technical Teachers CollegeAnhui Fengyang 233100 College of the Life Science and Technology Xinjiang UniversityUrumqi830046

Desertification has already become the global social problem. On the Arid zone it has closer relation with the frail ecotope. The system of the arid zone mountain belongs to crisscross between the farming ,forestry and husbandry . The frailty of the ecosystem manifests on the internal frailty, depends on the plant ,intensity of the contradictory between the landscape transitional and natural reservation area,physical weathering strong,the development of the soil surface is slowly but the erode of the rain ,soil erosion very grave. Lichens not only rein force the intensity and depth of the weathering of rocks and formation ,accelerate of the mineral weathering making and accumulating the organic compound, at the same time lichens have strongly water protection abilities and inestimable role in the prevent soil erosion. In this paper we were according to on-the-spot investigation and analysis of the laboratory from 1985 to now on the middle and west of the Mt . Tianshan and Mt. Altay kanas where mainly probe into the significance of the protection water and conservation water resources of the Arid zone. This research works will be provide scientific basis and reference of the government for put into effect ,improving environment of the mountain region ,major construction oasis ecotope and make great efforts for protection desert ecotope.

关键词： Lichens Water resource Mountain ecosystem