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近距离煤层孤岛区域上行开采技术研究与应用 被引量:5
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作者 赵广新 董凤宝 《煤矿开采》 2005年第5期22-24,共3页
由于地质条件的复杂性和不可预知性造成采空区上方遗弃了有可采价值的煤炭储量。通过理论分析与矿压观测等相结合的方法,研究上行开采的机理,掌握了采动压力的变化规律,确定了上下煤层采动影响的时空关系,及时采取相应措施,预计上行开... 由于地质条件的复杂性和不可预知性造成采空区上方遗弃了有可采价值的煤炭储量。通过理论分析与矿压观测等相结合的方法,研究上行开采的机理,掌握了采动压力的变化规律,确定了上下煤层采动影响的时空关系,及时采取相应措施,预计上行开采在安全控制方面的效果,为今后类似条件下进行上行开采提供宝贵资料。 展开更多
关键词 孤岛区域 上行开采 研究及应周
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新型高效水产饲料诱食剂——蚯蚓粉 被引量:4
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作者 赵朝阳 周鑫 《饲料博览(技术版)》 2008年第12期33-34,共2页
蚯蚓粉作为饲料添加剂具有丰富的营养价值,添加到水产饲料中可大大提高水产动物的摄食效率,提高免疫力,降低生产成本。文章就蚯蚓粉的加工制备,营养价值及其在水产饲料中的应用进行了阐述。
关键词 蚯蚓粉 营养价值 应周
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光纤通信技术在电力系统中的应用 被引量:1
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作者 刘汉汀 焦振 詹贞勇 《中国科技财富》 2011年第20期43-43,共1页
光纤通信技术在现代科技信息技术发展中发挥着重要的作用,本文就光纤通信技术在电力系统中的应用进行探讨。
关键词 光纤通信技术 电力系统 应周
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Bi-normalized response spectra and scalar periods for developing uniform seismic design spectra 被引量:3
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作者 徐龙军 谢礼立 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期266-271,共6页
Aiming at the uniform features of acceleration response spectra, two scalar periods-the response spectral predominant period Tp and the smoothed spectral predominant period To are employed to normalize the abscissa of... Aiming at the uniform features of acceleration response spectra, two scalar periods-the response spectral predominant period Tp and the smoothed spectral predominant period To are employed to normalize the abscissa of the normalized response spectra (NRS) of ground motions, respectively. Engineering characteristics of 5% -damped NRS, and the bi-normalized response spectra (BNRS) are investigated accounting for the effects of soil condition and fault distance. Nearly 600 horizontal ground motion components during the Chi-Chi earthquake are included in the analysis. It shows that the NRS strongly depends on soil condition and fault distance. However, soil condition and distance have only a slight influence on two kinds of BNRS. Dispersion analysis indicates that such normalization can reduce scatter in the derivation of response spectral shapes. Finally, a parametric analysis of the scalar periods (Tp, To) is performed and then compared with those of previous studies. These special and particular aspects of earthquake response spectra and scalar periods need to be considered in developing earthquake-resistant design criteria. 展开更多
关键词 ground motion normalized response spectrum bi-normalized response spectra scalar period
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New LCA Approach with Fuzzy Evaluation 被引量:5
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作者 张之敬 王信义 曹默 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期56-62,共7页
A quantitative and comprehensive method of product life cycle assessment(LCA) with fuzzy theory is developed, which will help designers to select the optimum design scheme for product life cycle design(LCD). Based on ... A quantitative and comprehensive method of product life cycle assessment(LCA) with fuzzy theory is developed, which will help designers to select the optimum design scheme for product life cycle design(LCD). Based on the theory of multiple attribute decision making, an algorithm of comprehensive and comparative evaluation for product environmental adaptability is presented. A program is built and used in an example of design improvement. The result shows that the proposed method and algorithm are practical and effective to the development of green products. 展开更多
关键词 life cycle assessment(LCA) fuzzy evaluation environment adaptability life cycle design(LCD) green products
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实质重于形式原则在会计实务中的应用 被引量:1
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作者 邓伟霞 姜小梅 《商业经济》 2007年第5期49-50,共2页
遵循“实质重于形式”原则是解决会计信息真正做到真实和相关的一条途径。“实质重于形式”原则在会计要素的确认、会计政策的选择、会计信息的披露等方面的应用,既能促使会计信息达到“决策有用性”的目标,又能在一定程度上减少企业利... 遵循“实质重于形式”原则是解决会计信息真正做到真实和相关的一条途径。“实质重于形式”原则在会计要素的确认、会计政策的选择、会计信息的披露等方面的应用,既能促使会计信息达到“决策有用性”的目标,又能在一定程度上减少企业利用会计核算方式操纵利润的机会。 展开更多
关键词 实质重于形式 原则 会计实务 应周
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Effects of Nanometer Hydroxyapatite on Proliferation of Periodontal Ligament Fibroblasts 被引量:2
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作者 孙卫斌 吴亚菲 +1 位作者 丁一 刘天佳 《Journal of Nanjing Medical University》 2004年第6期288-292,共5页
Objective:To investigate possible effects of nanophase powder of hydroxyapatite on proliferation of periodontal ligament cells. Methods: With sol-gel method, the nanophase hydroxyapatite powders were fabricated. These... Objective:To investigate possible effects of nanophase powder of hydroxyapatite on proliferation of periodontal ligament cells. Methods: With sol-gel method, the nanophase hydroxyapatite powders were fabricated. These powders were proved nanopaticles by transmission electron microscope. The effects on proliferation of periodontal ligament cell(PDLC) were observed in vitro with MTT [3-(4,5dimethylthiazo;-2-yl)-2,5-diphenytetralium bromide] method. Results: On the 2nd,3rd,4th day after treated with nanoparticles of hydroxyapatite, the proliferate activity of the PDLC increases significantly, compared with those with dense hydroxyaoatite and control but no significant difference could be found between the dense hydroxyapatite and the control. Conclusion: Nanophase hydroxyapatite can promote the regeneration of periodontal tissue. 展开更多
关键词 HYDROXYAPATITE nanoparticle material periodontal disease
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Impacts and Countermeasures of Climate Change on Animal Husbandry in Qinghai Plateau and Its Surrounding Area 被引量:8
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作者 李红梅 李林 +1 位作者 邓振镛 黎明 《Agricultural Science & Technology》 CAS 2010年第7期138-144,共7页
The paper aims to study the impacts and countermeasures of climate change on animal husbandry in Qinghai plateau and its surrounding area,and evaluate the effect of countermeasures.Results showed that:First,the annua... The paper aims to study the impacts and countermeasures of climate change on animal husbandry in Qinghai plateau and its surrounding area,and evaluate the effect of countermeasures.Results showed that:First,the annual mean temperature,annual mean maximum temperature and annual mean minimum temperature showed an increasing trend in Qinghai plateau during the time from 1961 to 2008; the annual precipitation had not obvious change,but the obvious feature of seasonal change; wind speed and sunshine hours showed a decreasing trend during the time from 1961 to 2008.Secondly,under the current climate condition,grassland productivity showed a decreasing trend,and the grassland theoretical capacity affected by grassland productivity decreased too; warm winter was in favor of livestock overwintering safely,which resulted in a high level of the survival rate of young stock; temperature increasing and precipitation decreasing were beneficial to the fatness of livestock,but the meat yield of livestock was affected by some negative factors such as grassland degradation; livestock diseases had a close relationship with weather condition,and adverse weather condition may arose many diseases of livestock.Thirdly,in view of the current problems of livestock production,we took a series of countermeasures including grass industry construction,livestock improvement,developing new modes of animal husbandry,control and prevention of stockbreeding diseases and insect pests and recovery of meteorological disasters,which played a important role in promoting grassland productivity,solving the problem of the imbalances between livestock and forage,protecting the ecological environment and improving livestock performance. 展开更多
关键词 Climate change Qinghai plateau and its surrounding area Animal Husbandry Impact COUNTERMEASURES
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p21^(WAF1/CIP1) Gene DNA Sequence Change and Their Relationship with the Phenotype of Human Osteosarcoma
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作者 张春林 廖威明 +2 位作者 李佛保 曾炳芳 曾益新 《The Chinese-German Journal of Clinical Oncology》 CAS 2004年第1期37-41,66,共6页
Objective: To investigate the p21WAF1 /CIP1gene DNA sequence change and their relationship with the phenotype of human osteosarcoma. Methods: p21WAF1 /CIP1gene DNA of 36 osteosarcoma spec- ... Objective: To investigate the p21WAF1 /CIP1gene DNA sequence change and their relationship with the phenotype of human osteosarcoma. Methods: p21WAF1 /CIP1gene DNA of 36 osteosarcoma spec- imens was examined by using polymerase chain reaction-single strand conformation polymorphism (PCR- SSCP) method. The PCR products were sequenced directly. Results: In p21WAF1 /CIP1 gene exon3 of 36 cases of human osteosarcoma, the change of C→T in the p21WAF1 /CIP1gene CDNA sequence of position 609th occurred in 17 cases with the incidence being 44.4%. In 10 normal blood samples, DNA sequence analysis showed the change of C→T in the p21WAF1 /CIP1gene CDNA sequence of position 609th occurred in 8 cases with the incidence being 80%. Conclusion: The novel location of p21WAF1 /CIP1gene polymorphism of osteosarcoma, but not mutation was de?ned, and this location might provide the meaningful reference for the further research of p21WAF1/CIP1 gene.p2lWAF1/CIP1基因DNA序列分析及其与骨肉瘤表型的关系 展开更多
关键词 p21WAF1 /CIP1 gene OSTEOSARCOMA PCR-SSCP DNA sequencing
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Salsa dance and Zumba fitness: Acute responses during community-based classes 被引量:1
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作者 Pablo A.Domene Hannah J.Moira +1 位作者 Elizabeth Pummell Chris Easton 《Journal of Sport and Health Science》 SCIE 2016年第2期190-196,共7页
Background: Research interest in both partnered Latin dance and non-partnered Latin-themed aerobic dance has increased in recent years, likely a result of the gaining popularity of these types of instructor-led group... Background: Research interest in both partnered Latin dance and non-partnered Latin-themed aerobic dance has increased in recent years, likely a result of the gaining popularity of these types of instructor-led group classes among the mainstream dance and fitness audiences; however, the efficacy of these activities for the purposes of health promotion currently remains unclear. The purpose of this study was to simultaneously assess the physiological responses and psychological experiences during salsa dance and Zumba fitness in a community sample of physically inactive women. Methods: Twenty-four participants, aged 22-56 years, visited the laboratory to perform a graded exercise test for determination of maximal oxygen uptake and maximal heart rate. The participants then attended 2 partnered salsa dance and 2 non-partnered Zumba fitness classes each in a counterbalanced order over a 2-week period. The 1-h classes were taught by certified instructors in established venues in the Royal Borough of Kingston and the surrounding communities of London, UK. Physiological data were collected using a wrist-worn ActiGraph wGT3X+ acceler- ometer with accompanying heart rate monitor and were processed using previously validated dance-specific techniques. Psychological experiences were measured via the Subjective Exercise Experiences Scale. Results: There was a significantly higher (p 〈 0.001) total time spent in moderate-to-vigorous physical activity (51.2± 3.1 vs. 32.6 ±5.9 min), total energy expenditure (411±66 vs. 210 ± 46 kcal), and total step count (6773 ± 556 vs. 4108 ±781 steps) during Zumba fitness when compared to salsa dance. Significant pre- to post-class improvements in positive well-being (p 〈 0.01, partial 7/2 = 0.4l) and psychological distress (p 〈 0.001, partial 02 = 0.72) were simultaneously observed for both salsa dance and Zumba fitness. Conclusion: The acute responses to classes of partnered Latin dance and non-partnered Latin-themed aerobic dance suggest that in physically inactive women participation is indeed efficacious in terms of community-based physical activity and psychosocial health promotion. 展开更多
关键词 ACCELEROMETRY AEROBICS Cultural dance EXERCISE Physical acti ~ity
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High-cycle fatigue behavior of friction stir butt welded 6061 aluminium alloy 被引量:8
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作者 Hrishikesh DAS Debayan CHAKRABORTY Tapan KUMAR PAL 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期648-656,共9页
Friction stir welding (FSW) of 6061 aluminium alloy butt joint was carried out at each rotation speed of 600, 800, 1000, 1200 r/min for two different travel speeds, 80 and 100 mm/min, at a constant probe depth of 1.... Friction stir welding (FSW) of 6061 aluminium alloy butt joint was carried out at each rotation speed of 600, 800, 1000, 1200 r/min for two different travel speeds, 80 and 100 mm/min, at a constant probe depth of 1.85 mm. The calculated energy input based on the FSW parameters studied shows that the ultimate tensile strength (UTS) of the butt joint is obtained within a certain range of energy input of 297 kJ to 354 kJ out of total range of energy input studied from 196 kJ to 405 kJ. The fatigue behaviors of high-strength and low-strength joints performed at different stress ratios, i.e., 0.5, 0.3, 0.1, -0.3, -0.5, indicate that the fatigue behaviors of both the welds are sensitive to the microstructural features, such as stir zone (SZ), thermo mechanically affected zone (TMAZ) and heat affected zone (HAZ). The observed fatigue strengths were discussed in terms of the microstructure, crack path behavior and fracture surface. 展开更多
关键词 Al alloy friction stir welding (FSW) high cycle fatigue stress ratio (R-ratio) crack path
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回归原典:学术批评的必要与必须——由《水经注》引发的一场学术争论
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作者 李艳凤 王嘉川 《南京晓庄学院学报》 2006年第5期32-35,共4页
郦道元《水经注》不但资料宏富,而且写作态度极为严谨端正,宁可存疑备考,不作硬性牵合;其中有关“萬城”之记事,即是其异说并存、传疑备考的典型事例。这为后人提供了进一步深入考证的余地。明代学者如杨慎、陈耀文、王世贞、胡应麟、周... 郦道元《水经注》不但资料宏富,而且写作态度极为严谨端正,宁可存疑备考,不作硬性牵合;其中有关“萬城”之记事,即是其异说并存、传疑备考的典型事例。这为后人提供了进一步深入考证的余地。明代学者如杨慎、陈耀文、王世贞、胡应麟、周婴,乃至当今的林庆彰先生,都曾先后对此问题展开探讨,其中有正有误,而其一切的误解误说,皆由未能检核《水经注》原书所致。这表明,要开展正确的学术研究与学术批评,要对客观事物有正确的认识,不管头绪如何纷繁复杂,都只有从原典原著入手这一条路。回归原典,重读原典,准确把握和理解原典,是学术研究与学术批评的必要与必须。 展开更多
关键词 萬城 杨慎 胡应麟 周婴
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Influence of Perioperative Blood Transfusion on Prognosis in Patients with Colon Cancer 被引量:3
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作者 LIANG Han WANG Xiaona WANG Baogui PAN Yuan LIU Ning WANG Dianchang HAO Xishan 《The Chinese-German Journal of Clinical Oncology》 CAS 2006年第4期261-267,共7页
Objective: To explore the influence of perioperative blood transfusion on the postoperative survival of patients with colon cancer. Methods: Univariate and multivariate retrospective analyses were performed on the s... Objective: To explore the influence of perioperative blood transfusion on the postoperative survival of patients with colon cancer. Methods: Univariate and multivariate retrospective analyses were performed on the survival in a total of 723 colon cancer patients which were treated surgically during a period of 10 years. Results: Kaplan-Meier estimates showed that more than 800 mL perioperative blood transfusion was the survival predictor. Blood transfusion influenced significantly the prognosis of patients 40 years old and younger, those undergoing helicoloectomy left side, those with papillary adenocarcinoma, those with big tumors (diameter ≥ 8 cm), those with stage Ⅰ tumors, those with lymphatic node metastases and those without liver metastases. In multivariate analysis only the tumor location, radicality of operation, lymphatic invasion, liver metastasis, depth of tumor invasion and TNM stage retained their significance. Conclusion: Perioperative blood transfusion is some extent. The indication of blood transfusion the prognostic factor for patients with colon cancer to must be restricted strictly, specially in patients younger than 40 years old, with right side lesion, papillary adenocarcinoma, big tumors (diameter ≥8 cm), stage Ⅰ tumors and lymphatic node metastases or without liver metastases. But perioperative blood transfusion may not be deleterious for patients with staging Ⅳ disease and with distant metastases. 展开更多
关键词 CANCER COLON SURGERY blood transfusion PROGNOSIS
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Application of system dynamics for assessment of sustainable performance of construction projects 被引量:10
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作者 SHENL.Y. 吴宇哲 +1 位作者 CHANE.H.W. HAOJ.L. 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第4期339-349,共11页
Sustainable performance is expected to become a major factor when examining the feasibility of a construction project in terms of its life cycle performance. The study on which this paper is based developed a simulati... Sustainable performance is expected to become a major factor when examining the feasibility of a construction project in terms of its life cycle performance. The study on which this paper is based developed a simulation model, using system dy- namics methodology, to assess the sustainable performance of projects. Three major factors are used to examine project sus- tainable performance (PSP): the sustainability of economic development (E), the sustainability of social development (S), and the sustainability of environmental development (En). Sustainable development ability (SDA) was used as a prototype to evaluate the degree of sustainable performance. The simulation software ‘ithink’ was used to help with the application of the model to a real life case. This paper explains and demonstrates the procedures used to develop the model and finally offers an approach for assessing the feasibility of a construction project in terms of its sustainable performance. 展开更多
关键词 Construction project Project life cycle Project sustainable performance (PSP) Sustainable development ability(SDA) System dynamics Simulation
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DAMAGE TOLERANCE AND FATIGUE LIFE ESTIMATION FOR PIPE/ROD BAR STRUCTURE
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作者 Dura Hari Bahadur 吴铁鹰 吴志功 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第2期169-175,共7页
The damage tolerance for pipe/rod bar in the auxiliary power units (APUs) support system is studied. The main objective is to study whether planes can safely land when the fatigue crack appears on the bar. Firstly, ... The damage tolerance for pipe/rod bar in the auxiliary power units (APUs) support system is studied. The main objective is to study whether planes can safely land when the fatigue crack appears on the bar. Firstly, the stress intensity factors (K~) of two bar structures are computed, and the iso-stress intensity factor (iso-Kl) model is presented. The model uses the finite element model (FEM) instead of the parameters of material to com- pute the crack propagation. Then, the general relations between Kt vs crack size are obtained for different mate- rials, inner to outer diameter ratios (D^n/Dout) and external crack propagation angles (0). Finally, the FEM anal- ysis results are input to the ANSYS parametric design language(ANSYS-APDL) software. And the fatigue life of damaged bar is estimated under the condition of loading spectrum. 展开更多
关键词 fatigue crack propagation circumferential crack stress intensity factor pipe/rod bar
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Immune response of Pseudosciaena crocea to the injection of Vibrio alginolyticus 被引量:1
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作者 鄢庆枇 张俊杰 +3 位作者 邹文政 陈强 庄峙厦 王小如 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第1期85-91,共7页
For the investigation of anti-infection immune response of Pseudosciaena crocea, 160 healthy fish samples were categorized into infected and control groups. Each individual fish in the infected group was injected intr... For the investigation of anti-infection immune response of Pseudosciaena crocea, 160 healthy fish samples were categorized into infected and control groups. Each individual fish in the infected group was injected intraperitoneally (i.p.) with 0.2 ml bacterial suspension of Vibrio alginolyticus in density of 2×107 CFU/ml, while each individual in the control group was injected i.p. with 0.2 ml sterile saline solution (0.85%). It was observed that the artificial injection of V. alginolyticus significantly increased the number of erythrocytes, leucocytes, lymphocytes in peripheral blood as well as peripheral serum antibacterial activity and antibody titer of large yellow croaker, and significantly reduced the number of peripheral blood granulocytes as compared with those in the control group. No significant difference in acid phosphytase and superoxide dismutase activity of serum was detected between the two groups. It is suggested that non-specific immune factors including leucocytes and anti-bacteria substance in peripheral blood played important role at the initial stage of infection, and specific immune factors such as antibody then played important role in response to anti-infection at the latter stage. 展开更多
关键词 Pseudosciaena crocea Vibrio alginolyticus artificial infection immune response
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Significance of preoperative C-reactive protein as a parameter of the perioperative course and long-term prognosis in squamous cell carcinoma and adenocarcinoma of the oesophagus 被引量:12
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作者 Ines Gockel Kathrin Dirksen +1 位作者 Claudia M Messow Theodor Junginger 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第23期3746-3750,共5页
AIM: C-reactive protein (CRP) is an acute-phase reactant and a known indicator of the malignant potential of the tumour. The aim of this study was to investigate the significance of preoperative CRP as a parameter ... AIM: C-reactive protein (CRP) is an acute-phase reactant and a known indicator of the malignant potential of the tumour. The aim of this study was to investigate the significance of preoperative CRP as a parameter of the perioperative course and long-term prognosis in patients with squamous cell carcinoma and aclenocarcinoma of the oesophagus. METHODS: Serum CRP was determined preoperatively in 291 of 371 patients undergoing oesophagectomy for cancer from December 1989 to March 2004. Median patient age was 59 (28-79) year, 82.5% of patients were males. Squamous cell carcinoma was diagnosed in 151 (51.9%) and aclenocarcinoma in 122 patients. Transhiatal oesophagectomy was clone in 151 (51.9%) patients and 134 (46.0%) patients underwent the abclominothoracic procedure. RESULTS: In 127 (43.6%) patients the preoperative serum CRP concentration was within the normal range (〈 5 mg/clL), elevated CRP levels were measured in 164 (56.4%) patients. Tumour extension (P 〈 0.0005) and the number of lymph nodes affected by metastatic spread (P = 0.015) were significantly increased in the group with elevated CRP levels. Among the perioperative parameters both the number of blood transfusions (P = 0.006) and the general complication rate (P = 0.002) were higher in patients with elevated preoperative CRP levels. The long-term survival rate of 13.6 (0-109.8) mo was poorer in the group with elevated CRP levels compared to 18.9 (0-155.4) mo in the group with normal CRP levels (log-rank test: P = 0.107). Multivariateanalysis with backward variables selection identified preoperative CRP as an independent prognostic factor of the long-term prognosis in patients with oesophageal carcinoma, with a hazard ratio of 1.182 (95% confidence interval: 1.030-1.356). CONCLUSION: The preoperative serum CRP-level is an easily determined independent prognostic marker in patients with squamous cell carcinoma and adenocarcinoma of the oesophagus. 展开更多
关键词 Preoperative C-reactive protein Perioperativecourse Long-term prognosis Squamous cell carcinoma Aclenocarcinoma OESOPHAGUS
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Role of Periodic Input Composition and Sweeping Gas for Improvement of Hydrogen Production in a Palladium Membrane Reactor by Partial Oxidation of Methane
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作者 Lemnouer Chibane Brahim Djellouli 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第3期577-588,共12页
The partial oxidation of methane under periodic operation over Ni/y/-Al2O3 catalyst was investigated in a Pd-membrane reactor. The effects of key parameters such as the inlet composition and the sweeping, gas on metha... The partial oxidation of methane under periodic operation over Ni/y/-Al2O3 catalyst was investigated in a Pd-membrane reactor. The effects of key parameters such as the inlet composition and the sweeping, gas on methane conversion and the hydrogen recovery are numerically estalallshed with two penodtc input ttmctlons. In order to analyze the effect of the inputs modulation, the reaction was performed under low steam to methane ratio at a mod-erate temperature and pressure. It was obtained that to achieve process intensification is to operate the process in a periodic way. The main results show that the periodic input functions can improve the performance of the process compared to the optimal steady state operation. Moreover, there is an optimum amplitude of manipulated inputs leads to a maximum of hydrogen recovery. It is noteworthy that the comparison between the predicted performancevia the sinusoidal and the'square ways show that the better'average performance was obtainedwith the square way. 展开更多
关键词 hydrogen production MODULATION periodic operation Pd-membrane reactor
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Optimal production lot sizing model in a supply chain with periodically fixed demand considering learning effect 被引量:1
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作者 熊中楷 SHEN Tiesong 《Journal of Chongqing University》 CAS 2002年第2期86-88,共3页
This paper presents an optimal production model for manufacturer in a supply chain with a fixed demand at a fixed interval with respect to the learning effect on production capacity. An algorithm is employed to find t... This paper presents an optimal production model for manufacturer in a supply chain with a fixed demand at a fixed interval with respect to the learning effect on production capacity. An algorithm is employed to find the optimal delay time for production and production time sequentially. It is found that the optimal delay time for production and the production time are not static, but dynamic and variant with time. It is important for a manufacturer to schedule the production so as to prevent facilities and workers from idling. 展开更多
关键词 learning curve capacity expansion supply chain optimal production policy.
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A generalized sinusoidal model and its applications
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作者 库少平 《Journal of Chongqing University》 CAS 2009年第1期70-74,共5页
A physical model of sinusoidal function was established. It is generalized that the force is directly proportional to a power function of the distance in a classical spring-oscillator system. The differential equation... A physical model of sinusoidal function was established. It is generalized that the force is directly proportional to a power function of the distance in a classical spring-oscillator system. The differential equation of the generalized model was given. Simulations were conducted with different power values. The results show that the solution of the generalized equation is a periodic function. The expressions of the amplitude and the period(frequency) of the generalized equation were derived by the physical method. All the simulation results coincide with the calculation results of the derived expressions. A special function also was deduced and proven to be convergent in the theoretical analysis. The limit value of the special function also was derived. The generalized model can be used in solving a type of differential equation and to generate periodic waveforms. 展开更多
关键词 sinusoidal function sinusoidal model differential equation waveform generator
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