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Short-term efficacy of natural orifice specimen extraction surgery for low rectal cancer 被引量:16
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作者 Jun-Hong Hu Xing-Wang Li +4 位作者 Chen-Yu Wang Jun-Jie Zhang Zheng Ge Bing-Hui Li Xu-Hong Lin 《World Journal of Clinical Cases》 SCIE 2019年第2期122-129,共8页
BACKGROUND This case-control study compared the short-term clinical efficacy of natural orifice specimen extraction surgery(NOSES) using a prolapsing technique and the conventional laparoscopic-assisted approach for l... BACKGROUND This case-control study compared the short-term clinical efficacy of natural orifice specimen extraction surgery(NOSES) using a prolapsing technique and the conventional laparoscopic-assisted approach for low rectal cancer.AIM To further explore the application value of the transanal placement of the anvil and to evaluate the short-term efficacy of NOSES for resecting specimens of low rectal cancer, as well as to provide a theoretical basis for its extensive clinical application.METHODS From June 2015 to June 2018, 108 consecutive laparoscopic-assisted low rectal cancer resections were performed at our center. Among them, 26 specimens were resected transanally using a prolapsing technique(NOSES), and 82 specimens were resected through a conventional abdominal wall small incision(LAP). A propensity score matching method was used to select 26 pairs of matched patients, and their perioperative data were analyzed.RESULTS The baseline data were comparable between the two matched groups. All 52 patients underwent the surgery successfully. The operative time, blood loss,number of harvested lymph nodes, postoperative complication rate,circumferential margin involvement, postoperative follow-up data, and postoperative anal function were not statistically significant. The NOSES group had shorter time to gastrointestinal function recovery(2.6 ± 1.0 d vs 3.4 ± 0.9 d, P= 0.006), shorter postoperative hospital stay(7.1 ± 1.7 d vs 8.3 ± 1.1 d, P = 0.003),lower pain score(day 1: 2.7 ± 1.8 vs 4.6 ± 1.9, day 3: 2.0 ± 1.1 vs 4.1 ± 1.2, day 5: 1.7± 0.9 vs 3.3 ± 1.0, P < 0.001), a lower rate of additional analgesic use(11.5% vs61.5%, P = 0.001), and a higher satisfaction rate in terms of the aesthetic appearance of the abdominal wall after surgery(100% vs 23.1%, P < 0.001).CONCLUSION NOSES for low rectal cancer can achieve satisfactory short-term efficacy and has advantages in reducing postoperative pain, shortening the length of postoperative hospital stay, and improving patients' satisfaction in terms of a more 展开更多
关键词 Natural ORIFICE SPECIMEN EXTRACTION SURGERY Low RECTAL cancer Laparoscopy Prolapsing technique no auxiliary INCISION
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地下储气库盐穴及盐层固井技术 被引量:16
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作者 尹学源 《石油钻采工艺》 CAS CSCD 北大核心 2007年第1期92-94,共3页
分析了西气东输地下储气库盐穴及盐层固井存在盐穴无井底、盐层固井、井底温度较高、井眼尺寸大、水泥石长期胶结性能要求高等固井技术难点,采用打水泥塞建立人工井底、半饱和盐水水泥浆体系、提高大井眼顶替效率等技术措施,解决了采卤... 分析了西气东输地下储气库盐穴及盐层固井存在盐穴无井底、盐层固井、井底温度较高、井眼尺寸大、水泥石长期胶结性能要求高等固井技术难点,采用打水泥塞建立人工井底、半饱和盐水水泥浆体系、提高大井眼顶替效率等技术措施,解决了采卤井老井改造固井技术难题,实现了无井底盐穴固井,通过改进欠饱和盐水水泥浆性能,提高了新腔钻井的盐膏层固井质量。在江苏金坛盐矿完成的6口储气库盐穴固井和8口新腔钻井固井作业表明,该固井技术适合储气库盐穴盐层固井的需要,可以提高固井质量。 展开更多
关键词 储气井 盐穴 无井底 盐层 顶替效率 固井技术
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A new differential absorption lidar for NO_2 measurements using Raman-shifted technique 被引量:12
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作者 胡顺星 胡欢陵 +5 位作者 张寅超 周军 岳古明 谭琨 纪玉峰 徐贲 《Chinese Optics Letters》 SCIE EI CAS CSCD 2003年第8期435-437,共3页
Based on Raman-shifted wavelengths of D2 and CHr pumped by third harmonic of Nd:YAG laser, a differential absorption lidar was presented in this paper and had been constructed for probing environmental NO2 concentrati... Based on Raman-shifted wavelengths of D2 and CHr pumped by third harmonic of Nd:YAG laser, a differential absorption lidar was presented in this paper and had been constructed for probing environmental NO2 concentration. NO2 experimental measurements were carried out at Anhui Institute of Optics and Fine Mechanics in Hefei. Some NO2 measurement results were given and discussed. 展开更多
关键词 for Nd as of YAG A new differential absorption lidar for no2 measurements using Raman-shifted technique nm no
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稻茬免耕直播油菜覆盖稻草栽培技术研究 被引量:12
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作者 王月星 周伟军 +1 位作者 吴美娟 黄洪明 《中国农学通报》 CSCD 2006年第7期209-211,共3页
为降低油菜生产成本,对稻茬免耕直播油菜覆盖稻草栽培技术进行试验研究。播种期设10月20日、10月30日、11月9日3期播种,种植密度设18万株/hm2、27万株/hm2、36万株/hm23水平,稻草覆盖数量设0、2250kg/hm2、4500kg/hm23水平。试验结果表... 为降低油菜生产成本,对稻茬免耕直播油菜覆盖稻草栽培技术进行试验研究。播种期设10月20日、10月30日、11月9日3期播种,种植密度设18万株/hm2、27万株/hm2、36万株/hm23水平,稻草覆盖数量设0、2250kg/hm2、4500kg/hm23水平。试验结果表明:播种期对免耕直播油菜产量影响大,适期早播是高产的关键;播种后覆盖稻草,能抑制杂草、提高地温和培肥地力;种植密度18万~36万株/hm2范围内,产量差异不显著。浙江省免耕直播油菜高产农艺措施为10月20日撒直播、种植密度27万株/hm2、稻草覆盖量2250kg/hm2。 展开更多
关键词 直播油菜 免耕 栽培技术 产量
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基于激光光谱差分法检测NO_2 被引量:8
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作者 林伟豪 高致慧 +2 位作者 杨勇 黄必昌 贺威 《激光技术》 CAS CSCD 北大核心 2014年第6期835-838,共4页
为了分析大气污染的主要污染气体之一的二氧化氮(NO2)的光谱与气体体积分数之间的关系,采用了中心波长位于NO2高吸收峰位置的激光作为检测光源,建立了光谱气体检测系统。根据朗伯-比尔定律,采用分时差分方法,结合权威数据库对比,并考虑... 为了分析大气污染的主要污染气体之一的二氧化氮(NO2)的光谱与气体体积分数之间的关系,采用了中心波长位于NO2高吸收峰位置的激光作为检测光源,建立了光谱气体检测系统。根据朗伯-比尔定律,采用分时差分方法,结合权威数据库对比,并考虑光谱线宽度等因素影响,进行光谱分析,用最小二乘法进行数据拟合,取得了NO2吸收光谱与其体积分数的关系曲线数据,并进行了体积分数反演和误差分析。结果表明,实验结果与理论分析相吻合,验证了光谱检测对NO2检测的研究与应用价值。 展开更多
关键词 光谱学 激光技术 光谱差分法 气体体积分数 二氧化氮 no2
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鄂北地区稻茬小麦免耕机械条播增产增效分析 被引量:7
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作者 郭光理 郑威 +5 位作者 许燕子 张勇 曹邦志 汤颢军 朱展望 高春保 《湖北农业科学》 北大核心 2014年第23期5669-5672,共4页
2010年以来连续3年在鄂北地区开展了稻茬小麦免耕栽培试验。对免耕机械条播和常规栽培稻茬小麦的次生根和分蘖发生、穗粒数及实际产量进行了比较,并对免耕机械条播稻茬小麦的生产效益进行了分析.研究稻茬小麦免耕栽培技术的应用效果... 2010年以来连续3年在鄂北地区开展了稻茬小麦免耕栽培试验。对免耕机械条播和常规栽培稻茬小麦的次生根和分蘖发生、穗粒数及实际产量进行了比较,并对免耕机械条播稻茬小麦的生产效益进行了分析.研究稻茬小麦免耕栽培技术的应用效果,分析稻茬小麦免耕栽培技术增产增效的原因。结果表明,在小麦6.6叶龄时,免耕机械条播稻茬小麦次生根条数为10.8条,分蘖2.2个,比对照分别增加2.2条和0.5个。免耕机械条播稻茬小麦子粒产量比对照增加8.9%。14.0%.平均增加11.5%。2011-2013年.免耕条播稻茬小麦较对照平均节省人工10.5个/hm^2,合计节省投入2187.0元/hm^2.免耕条播稻茬小麦产量增收1050.9元/hm^2.合计比对照增加效益3237.9元/hm^2。 展开更多
关键词 稻茬小麦 机械条播 免耕 栽培技术
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冠状动脉微血管阻塞的临床及心脏磁共振研究进展 被引量:7
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作者 马敏 贺勇 《临床心血管病杂志》 CAS CSCD 北大核心 2017年第10期937-940,共4页
急性心肌梗死患者直接经皮冠状动脉介入(PCI)治疗的成功依赖于冠状动脉(冠脉)微循环功能和结构的完整性。冠脉微血管阻塞是急性心肌梗死患者再灌注治疗后常见的病理现象,其特征是在梗死区内由于心肌微血管的损伤和功能不全导致的"... 急性心肌梗死患者直接经皮冠状动脉介入(PCI)治疗的成功依赖于冠状动脉(冠脉)微循环功能和结构的完整性。冠脉微血管阻塞是急性心肌梗死患者再灌注治疗后常见的病理现象,其特征是在梗死区内由于心肌微血管的损伤和功能不全导致的"无复流"现象。微血管阻塞可以通过不同的影像技术评价,心脏磁共振影像不仅能够准确识别微血管阻塞现象,还能够进一步评估梗死程度及整个左心室功能。本文就微血管阻塞在心脏磁共振影像上的特征表现及通过对急性心肌梗死患者应用该影像技术辅助诊断和治疗的重要性作一综述。 展开更多
关键词 微血管阻塞 无复流 心肌内出血 心脏磁共振 影像技术
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Review and Analysis of Key Techniques in Marine Sediment Sampling 被引量:5
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作者 Shudong He Youduo Peng +2 位作者 Yongping Jin Buyan Wan Guangping Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第5期150-166,共17页
Deep-sea sediment is extremely important in marine scientific research,such as that concerning marine geology and microbial communities.The research findings are closely related to the in-situ information of the sedim... Deep-sea sediment is extremely important in marine scientific research,such as that concerning marine geology and microbial communities.The research findings are closely related to the in-situ information of the sediment.One prerequisite for investigations of deep-sea sediment is providing sampling techniques capable of preventing distortion during recovery.As the fruit of such sampling techniques,samplers designed for obtaining sediment have become indispensable equipment,owing to their low cost,light weight,compactness,easy operation,and high adaptability to sea conditions.This paper introduces the research and application of typical deep-sea sediment samplers.Then,a representative sampler recently developed in China is analyzed.On this basis,a review and analysis is conducted regarding the key techniques of various deep-sea sediment samplers,including sealing,pressure and temperature retaining,low-disturbance sampling,and no-pressure drop transfer.Then,the shortcomings in the key techniques for deep-sea sediment sampling are identified.Finally,prospects for the future development of key techniques for deep-sea sediment sampling are proposed,from the perspectives of structural diversification,functional integration,intelligent operation,and high-fidelity samples.This paper summarizes the existing samplers in the context of the key techniques mentioned above,and can provide reference for the optimized design of samplers and development of key sampling techniques. 展开更多
关键词 SAMPLER Sealing technique Pressure&temperature-retaining technique Low-disturbance sampling technique no-pressure drop transfer technique
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Unsedation colonoscopy can be not that painful: Evaluation of the effect of “Lamaze method of colonoscopy” 被引量:5
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作者 Shao-Ping Yu Xiao-Dong Lin +5 位作者 Guang-Yao Wu Song-Hu Li Zong-Quan Wen Xiao-Hong Cen Xian-Guang Huang Mei-Ting Huang 《World Journal of Gastrointestinal Endoscopy》 CAS 2015年第15期1191-1196,共6页
AIM: To evaluate the pain relieving effect of intervention with "Lamaze method of colonoscopy" in the process of colonoscopy.METHODS: Five hundred and eighty-five patients underwent colonoscopy were randomly... AIM: To evaluate the pain relieving effect of intervention with "Lamaze method of colonoscopy" in the process of colonoscopy.METHODS: Five hundred and eighty-five patients underwent colonoscopy were randomly divided into three groups, Lamaze group, anesthetic group and control group. Two hundred and twenty-four patients of Lamaze group, the "Lamaze method of colonoscopy" were practiced in the process of colonoscopy. The Lamaze method of colonoscopy is modified from the Lamaze method of childbirth, which helped patients to relieve pain through effective breathing control. One hundred and seventy-eight patients in anesthetic group accepted sedation colonoscopy. For 183 patients in control group, colonoscopy was performed without any intervention. The satisfactory of colon cleaning, intestinal lesions, intubation time, success ratio, pain grading and complications were recorded. All data were statistically analyzed.RESULTS: There were no significant differences at base line of the three groups(P > 0.05). Anesthetic group shows advantage in intubation time than the other two groups(P < 0.05). Lamaze group shows no advantagein intubation time than that in control group(P > 0.05). The anesthetic group showed an apparent advantage in relieving pain(P < 0.01). Therefore, the "Lamaze method of colonoscopy" performed in colonoscopy could relieve pain effectively comparing with control group(P < 0.05). The patients in anesthetic group had the highest incidence of complications(P < 0.05).CONCLUSION: The performance of the "Lamaze method of colonoscopy" in the process of colonoscopy could relieve patients' pain, minimize the incidence of complications, and is worthy promotion in clinical practice. 展开更多
关键词 COLOnoSCOPY no SEDATION PAIN Lamaze technique
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No-touch isolation technique in emergency pancreaticoduodenectomy for neoplastic hemorrhage: Two case reports and review of literature
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作者 Akihiro Cho Satoshi Katagiri +8 位作者 Masao Ota Shunsuke Onizawa Ryota Higuchi Toshiya Sugishita Yukiko Niwa Takeshi Ishita Toshihiko Mouri Akita Kato Moe Iwata 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1910-1917,共8页
BACKGROUND Emergency pancreaticoduodenectomy(EPD)is a rare event for complex periam-pullary etiology.Increased intraoperative blood loss is correlated with poor post-operative outcomes.CASE SUMMARY Two patients underw... BACKGROUND Emergency pancreaticoduodenectomy(EPD)is a rare event for complex periam-pullary etiology.Increased intraoperative blood loss is correlated with poor post-operative outcomes.CASE SUMMARY Two patients underwent EPD using a no-touch isolation technique,in which all arteries supplying the pancreatic head region were ligated and divided before manipulation of the pancreatic head and duodenum.The operative times were 220 and 239 min,and the blood loss was 70 and 270 g,respectively.The patients were discharged on the 14^(th) and 10^(th) postoperative day,respectively.Thirty-two patients underwent EPD for the treatment of neoplastic bleeding.The mean operative time was 361.6 min,and the mean blood loss was 747.3 g.The comp-lication rate was 37.5%.The in-hospital mortality rate was 9.38%.CONCLUSION The no-touch isolation technique is feasible,safe,and effective for reducing intraoperative blood loss in EPD. 展开更多
关键词 no-touch isolation technique PANCREATICODUODENECTOMY Emergency pancre-aticoduodenectomy Neoplastic bleeding Superior mesenteric artery first approach Case report
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论巴金的小说理论与批评 被引量:3
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作者 许德 《安徽师范大学学报(社会科学版)》 2003年第5期576-582,共7页
巴金的小说理论最具实践性,是他大量小说创作经验的总结和升华。他视创作为表达自己内心情感的需要,是自己生活的一部分;主张创作面向读者,"把心交给读者",和读者进行诚挚的情感交流;同时认为"艺术的最高境界是无技巧&qu... 巴金的小说理论最具实践性,是他大量小说创作经验的总结和升华。他视创作为表达自己内心情感的需要,是自己生活的一部分;主张创作面向读者,"把心交给读者",和读者进行诚挚的情感交流;同时认为"艺术的最高境界是无技巧",肯定情感是创作的主要内容,形式和技巧只是它的附庸。小说应当有其教化的功能和审美的功能。巴金的小说理论和批评总是围绕着表现情感这条主线,它是朴实无华、独树一帜的。 展开更多
关键词 情感 创作如同生活 把心交给读者 无技巧
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Analysis of High Yield and Efficiency Technique in Hybrid Rice Zhongzheyou No.1 被引量:6
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作者 刘伟明 《Agricultural Science & Technology》 CAS 2009年第2期73-76,96,共5页
To understand the high yield and efficiency technique in hybrid rice Zhongzheyou No. 1, we conducted the correlation analysis, regression analysis and path analysis of hybrid rice Zhongzheyou No. 1 based on the data o... To understand the high yield and efficiency technique in hybrid rice Zhongzheyou No. 1, we conducted the correlation analysis, regression analysis and path analysis of hybrid rice Zhongzheyou No. 1 based on the data of its ear, grain and weight at different yield levels. From this study, we put forward the high yield and efficiency technique in Zhongzheyou No. 1 .. on the basis of certain effective ear number, filled grains per ear should be mainly targeted with a consideration to 1 000-grain weight. 展开更多
关键词 Zhongzheyou no. 1 Single-cropping dce High Yield and Efficiency technique pathway
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免架体叠合板支撑结构受弯性能数值模拟
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作者 李朝臣 《现代制造技术与装备》 2024年第7期75-78,共4页
为了解决H型钢梁+叠合板组合楼盖在施工过程中的楼板支撑问题,提出了一种免架体支撑的、端部可调的叠合楼板支撑结构。该支撑结构由端部可调支座和对拼冷弯薄壁C型钢两部分组成。建立13个免架体叠合楼板支撑结构的有限元模型,研究其在... 为了解决H型钢梁+叠合板组合楼盖在施工过程中的楼板支撑问题,提出了一种免架体支撑的、端部可调的叠合楼板支撑结构。该支撑结构由端部可调支座和对拼冷弯薄壁C型钢两部分组成。建立13个免架体叠合楼板支撑结构的有限元模型,研究其在施工荷载作用下的受弯承载性能。分别研究C型钢板件厚度、腹板高度和翼缘宽度对支撑结构抗弯承载能力的影响,给出支撑结构的使用意见,结果表明使用意见可以较好地满足施工要求。 展开更多
关键词 免架体 支撑结构 C型钢 叠合板 施工技术 有限元
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麻沙山药1号特征特性及其栽培技术 被引量:6
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作者 陈菁瑛 苏海兰 +2 位作者 黄颖桢 赵云青 刘保财 《福建农业科技》 2015年第8期41-42,共2页
介绍山药新品种麻沙山药1号的特征特性,从播种育苗、移栽定植、田间管理、病虫害防治、采收贮藏等方面总结其关键栽培技术。
关键词 山药 新品种 麻沙山药1号 特征特性 栽培技术 Masha YAM no. 1
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The “No-touch” technique improves the survival of patients with advanced hepatocellular carcinomas treated by liver transplantation: A single-center prospective randomized controlled trial 被引量:1
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作者 Xin Lin Min Xiao +5 位作者 Yang-Jun Gu Heng-Kai Zhu Meng-Xia Li Li Zhuang Shu-Sen Zheng Qi-Yong Li 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2023年第3期253-262,共10页
Background:Liver transplantation(LT)is the best treatment for patients with hepatocellular carcinoma(HCC).However,the surgical technique needs to be improved.The present study aimed to evaluate the“no-touch”techniqu... Background:Liver transplantation(LT)is the best treatment for patients with hepatocellular carcinoma(HCC).However,the surgical technique needs to be improved.The present study aimed to evaluate the“no-touch”technique in LT.Methods:From January 2018 to December 2019,we performed a prospective randomized controlled trial on HCC patients who underwent LT.The patients were randomized into two groups:a no-touch technique LT group(NT group,n=38)and a conventional LT technique group(CT group,n=46).Operative outcomes and survival in the two groups were analyzed.Results:The perioperative parameters were comparable between the two groups(P>0.05).There was no significant difference between the two groups in disease-free survival(DFS)(P=0.732)or overall survival(OS)(P=0.891).Of 36 patients who were beyond the Hangzhou criteria for LT,the DFS of the patients in the NT group was significantly longer than that in the CT group(median 402 vs.126 days,P=0.025).In 31 patients who had portal vein tumor thrombosis(PVTT),DFS and OS in the NT group were significantly better than those in the CT group(median DFS 420 vs.167 days,P=0.022;2-year OS rate 93.8%vs.66.7%,P=0.043).In 14 patients who had diffuse-type HCCs,DFS and OS were significantly better in the NT group than those in the CT group(median DFS 141 vs.56 days,P=0.008;2-year OS rate 75.0%vs.33.3%,P=0.034).Multivariate analysis showed that for patients with PVTT and diffusetype HCCs,the no-touch technique was an independent favorable factor for OS(PVTT:HR=0.018,95%CI:0.001-0.408,P=0.012;diffuse-type HCCs:HR=0.034,95%CI:0.002-0.634,P=0.024).Conclusions:The no-touch technique improved the survival of patients with advanced HCC compared with the conventional technique.The no-touch technique may provide a new and effective LT technique for advanced HCCs. 展开更多
关键词 no-touch technique Liver transplantation Hepatocellular carcinoma Surgical procedure SURVIVAL
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Correlation,Regression and Path Analysis between Yield Traits and Yield of Yongyou No.9 被引量:4
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作者 张胜 林太赟 《Agricultural Science & Technology》 CAS 2011年第4期517-519,共3页
[Objective] The research aimed to understand the high and efficiency technique in intersubspecific hybrid rice Yongyou No.9.[Method] We conducted the correlation analysis,regression analysis and path analysis of inter... [Objective] The research aimed to understand the high and efficiency technique in intersubspecific hybrid rice Yongyou No.9.[Method] We conducted the correlation analysis,regression analysis and path analysis of intersubspecific hybrid rice Yongyou No.9 based on the data of its ear,grain and weight at different yield levels.[Result]The performance of ear,grain and weight in Yongyou No.9 showed significant difference among different yield levels.The enhancement of effective ears would restrain the number of per ear total grains.It was found that the direct contributions of main economic traits to yield were determined to be per ear total grainseffective earseed setting rate1 000-grain weight.[Conclusion]The high-yield and effective cultivation techniques were suggested as follows:on the basis of certain effective ear number,grain number per ear should be mainly focused with a consideration to 1 000-grain weight. 展开更多
关键词 Yongyou no.9 Single cropping late rice High yield and efficiency Cultivation technique
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稻—油轮作区油菜免耕撒直播高产栽培技术 被引量:4
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作者 姜宇龙 《现代农业科技》 2012年第9期70-70,80,共2页
总结了稻—油轮作区油菜免耕撒直播高产栽培技术,包括选种播种、合理施肥、田间管理、病虫草害防治等内容,以期为稻—油轮作区油菜免耕撒直播高产栽培提供技术参考。
关键词 油菜 免耕 撒直播 栽培技术 稻—油轮作区
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汀芋1号槟榔芋选育及高产栽培技术 被引量:4
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作者 戴南火 吴天长 《福建农业科技》 2015年第10期41-43,共3页
汀芋1号槟榔芋是从长汀县当家种白芽槟榔芋变异株中经多年选育而来的一种红芽槟榔芋,具有芋形美观、食味粉香、产量高、品质优、抗性强、适应性广等特点。总结该品种的主要特征特性和高产栽培技术。
关键词 槟榔芋 汀芋1号 选育 栽培技术
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NO_x光解测量装置的设计与测试 被引量:4
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作者 曹玮 曾立民 +1 位作者 吴宇声 于雪娜 《环境科学学报》 CAS CSCD 北大核心 2014年第11期2911-2917,共7页
根据二氧化氮的光解反应原理,自主设计、装配了一套氮氧化物光解反应装置,并将其与Thermo 42系列氮氧化物分析仪的化学发光检测室联用,进行了不同条件下(分别为标气流量、臭氧流量、光源温度、功率、样品湿度)NO2光解转化效率的测试.结... 根据二氧化氮的光解反应原理,自主设计、装配了一套氮氧化物光解反应装置,并将其与Thermo 42系列氮氧化物分析仪的化学发光检测室联用,进行了不同条件下(分别为标气流量、臭氧流量、光源温度、功率、样品湿度)NO2光解转化效率的测试.结果表明:进样流量为100~200 mL·min-1、光源温度为20℃、光源功率约为60 W(光密度约26 W·mL-1)的条件下,可得到较高的光解转化效率(约80%);臭氧流量及样品相对湿度对转化效率影响不大.在上述最佳转化效率的条件下,将其与PLC860-CLD88p(ECO PHYSICIS)进行了为期8 d的比对实验.结果显示:二者的NO2实际测量结果趋势基本一致:[NO2]ECO=0.908×[NO2]PKU+1.913(R2=0.955),初步证实了该套自主设计光解装置应用于实际观测的可靠程度. 展开更多
关键词 二氧化氮 氮氧化物 光解 测量技术
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基于激光NO_2气体检测研究 被引量:2
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作者 杨勇 高致慧 +3 位作者 曹志 杨锦辉 林怀钦 陈子聪 《激光技术》 CAS CSCD 北大核心 2012年第2期198-199,207,共3页
为了设计一种NO2气体检测系统,以实现对大气中NO2等污染气体进行有效监测、提高空气质量,采用激光光谱分析技术,根据NO2气体在可见光范围内的吸收光谱与强吸收峰位置,选取中心波长为443.2nm蓝光激光光源,搭建了的NO2气体检测实验平台。... 为了设计一种NO2气体检测系统,以实现对大气中NO2等污染气体进行有效监测、提高空气质量,采用激光光谱分析技术,根据NO2气体在可见光范围内的吸收光谱与强吸收峰位置,选取中心波长为443.2nm蓝光激光光源,搭建了的NO2气体检测实验平台。实验测定不同体积分数NO2气体的透射谱线,通过对不同体积分数NO2气体透射光谱分析,运用最小二乘法线性拟合计算得出系统吸光度与气体体积分数的线性关系。结果表明,实验系统能够实现对NO2气体的检测,检测灵敏度为10-4量级,具有较好应用价值。 展开更多
关键词 激光技术 吸收光谱 激光 no2
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