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Effect of Slow and Controlled Release Fertilizers on the Yield and Nutrient Use Efficiency of Hot Pepper in Qiu-bei 被引量:8
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作者 杜彩艳 段宗颜 +2 位作者 鲁耀 胡万里 陈拾华 《Agricultural Science & Technology》 CAS 2011年第5期761-764,共4页
[Objective] The aim of this study was to investigate the impacts of slow and controlled release fertilizers(SCRF)on the yield of qiubei hot pepper,its nutrient use efficiency and environment.[Method] Using Qiubei ho... [Objective] The aim of this study was to investigate the impacts of slow and controlled release fertilizers(SCRF)on the yield of qiubei hot pepper,its nutrient use efficiency and environment.[Method] Using Qiubei hot pepper(Capsicum frutescens L.)as the experimental material,we studied the fertilization effect and environment-protecting effect of SCRF.[Result] The result showed that SCRF could improve the agronomic characteristics of hot pepper.Compared to singly applied common fertilizers,SCRF increased economic yield by 20.90% and economic benefit by 13 234.35 Yuan/hm2,and the ratio of output to input was improved by 47.93%.In comparison with common straight fertilizers at same NPK proportion and rate,SCRF increased economic yield by 5.26% and economic benefit by 5 554.80 Yuan/hm2,and the ratio of output to input was improved by 9.91%.Under the reduced use of SCRF by 20%,SCRF increased economic yield by 12.38% and economic benefit by 9595.20 Yuan/hm2 compared with singly applied common fertilizers,and the ratio of output to input was improved by 65.95%.SCRF improved nitrogen,phosphorus and potassium use efficiencies by 12.42-17.53,3.35-5.24 and 5.37-14.02 percents respectively.[Conclusion] As the result of much reduced N and P application rates,SCRF would significantly economize fertilizer resources and minimize the pollution caused by the loss of fertilizer nutrients,which is of practical importance for environment protection. 展开更多
关键词 slow and controlled release fertilizer Qiubei hot pepper YIELD Nutrient use efficiency
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Effects of slow or controlled release fertilizer types and fertilization modes on yield and quality of rice 被引量:25
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作者 WEI Hai-yan CHEN Zhi-feng +9 位作者 XING Zhi-peng ZHOU Lei LIU Qiu-yuan ZHANG Zhen-zhen JIANG Yan HU Ya-jie ZHU Jin-yan CUI Pei-yuan DAI Qi-gen ZHANG Hong-cheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第10期2222-2234,共13页
There is limited information about the influence of slow or controlled release fertilizer(S/CRF) on rice yield and quality. In this study, japonica rice cultivar Nanjing 9108 was used to study the effects of three d... There is limited information about the influence of slow or controlled release fertilizer(S/CRF) on rice yield and quality. In this study, japonica rice cultivar Nanjing 9108 was used to study the effects of three different S/CRFs(polymer-coated urea(PCU), sulfur-coated urea(SCU), and urea formaldehyde(UF)) and two fertilization modes(both S/CRF and common urea(CU) as basal fertilizer, S/CRF as basal and CU as tillering fertilizer) on rice yield and quality. CU only was applied separately as control(CK). Results showed that, rice grain yield, chalky kernel rate, chalky area, overall chalkiness, and the content of gliadin, glutenin, and protein, all showed the trends of UF〉PCU〉SCU within the same fertilization mode, and showed the trends of S/CRF as basal and CU as tillering fertilizer〉both S/CRF and CU as basal fertilizer within the same type of S/CRF. In contrast, the contents of amylose, amylopectin, and starch, as well as taste value, and peak and hot viscosity showed trends of SCU〉PCU〉UF, and the trends of both S/CRF and CU as basal fertilizer〉S/CRF as basal and CU as tillering fertilizer. Among S/CRF treatments and fertilization modes, taste values of cooked rice were positively correlated with amylose, amylopectin, and starch contents, as well as gel consistency, peak viscosity, hot viscosity, and cool viscosity, while negatively correlated with globulin, gliadin, glutenin, and protein contents. The types of S/CRF and fertilization modes are important for improving rice yield and quality. Compared to CK, higher yield and similar quality of rice was achieved with UF as basal and CU as tillering fertilizer, and similar yield with improved appearance and eating and cooking quality of rice was achieved with either both UF and CU as basal fertilizer, or PCU as basal and CU as tillering fertilizer. 展开更多
关键词 type of slow or controlled release fertilizer fertilization mode YIELD QUALITY
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Synthesis and Performance of Polyurethane Coated Urea as Slow/controlled Release Fertilizer 被引量:10
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作者 LI Qingshan WU Shu +3 位作者 RU Tiejun WANG Limin XING Guangzhong WANG Jinming 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第1期126-129,共4页
Polyurethane coated urea slow/controlled release fertilizer was prepared based on urea granules, isocyanate, polyols and paraffin. Isocyanate reacted with polyols to synthesize the polyurethane skin layer on urea gran... Polyurethane coated urea slow/controlled release fertilizer was prepared based on urea granules, isocyanate, polyols and paraffin. Isocyanate reacted with polyols to synthesize the polyurethane skin layer on urea granules surface. Paraffin serves as a lubricant during syntheses of polyurethane skin layers. The structure and nutrient release characteristics of the polyurethane skin layers were investigated by FTIR, SEM and TG. Urea nitrogen slow-release behavior of the polyurethane coated urea was tested. The experimental results indicated that compact and dense polyurethane skin layers with a thickness of 10-15 lam were formed on urea surface, the urea nitrogen slow-release time can reach 40-50 days. Paraffin proves to play a key role in inhibiting water to penetrate into urea, but excessive addition would decrease the polyurethane crosslinking density. 展开更多
关键词 polyurethane elastomer coated urea slow / controlled release fertilizer PARAFFIN
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Release Characteristics of Different N Forms in an Uncoated Slow/Controlled Release Compound Fertilizer 被引量:14
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作者 DONG Yan WANG Zheng-yin 《Agricultural Sciences in China》 CAS CSCD 2007年第3期330-337,共8页
This study examined the release characteristics of different N forms in an uncoated slow/controlled-release compound fertilizer (UCRF) and the N uptake and N-use efficiency by rice plants. Water dissolution, soil le... This study examined the release characteristics of different N forms in an uncoated slow/controlled-release compound fertilizer (UCRF) and the N uptake and N-use efficiency by rice plants. Water dissolution, soil leaching, and pot experiments were employed. The dynamics of N release from the UCRF could be quantitatively described by three equations: the first-order kinetics equation [N1=N0 (1-e^-kt)], Elovich equation (N1=a + blnt), and parabola equation (N1=a + bt^0.5), with the best fitting by the first-order kinetics equation for different N (r= 0.9569^**-0.9999^**). The release potentials (No values estimated by the first-order kinetics equation) of different N in the UCRF decreased in the order of total N 〉 DON 〉 urea-N 〉 NH4^+-N 〉 NO3^-N in water, and total N 〉 NH4^+-N 〉 DON 〉 urea-N 〉 NO3^--N in soil, respectively, being in accordance with cumulative amounts of N release. The constants of N release rate (k values and b values) for different N forms were in decreasing order of total N 〉 DON 〉 NH4^+-N 〉 NO3^--N in water, whereas the k values were urea- N 〉DON 〉 NH4^+-N 〉 total N 〉 NO3^--N, and the b values were total N 〉 NH4^+-N 〉 DON 〉 NO3^--N 〉 urea-N in soil. Compared with a common compound fertilizer, the N-use efficiency, N-agronomy efficiency, and N-physiological efficiency of the UCRF were increased by 11.4%, 8.32 kg kg^-1, and 5.17 kg kg^-1, respectively. The ratios of different N to total N in the UCRF showed significant correlation with N uptake by rice plants. The findings showed that the first-order kinetics equation [Nt=N0 (l-e^kt)] could be used to describe the release characteristics of different N forms in the fertilizer. The UCRF containing different N forms was more effective in facilitating N uptake by rice compared with the common compound fertilizer containing single urea-N form. 展开更多
关键词 slow/controlled release compound fertilizer nitrogen forms release kinetics nitrogen use efficiency
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Application of Lignin and Its Derivatives as Slow/Controlled Release Materials in Agricultural Fields 被引量:4
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作者 YingJuan Fu MengHua Qin +1 位作者 ZhaoJiang Wang ZongQuan Li 《Paper And Biomaterials》 2018年第1期53-62,共10页
Lignin is the main by-product of pulp and papermaking and is not effectively utilized. Conversion of industrial lignins into value-added materials is beneficial for the effective utilization of resources as well as fo... Lignin is the main by-product of pulp and papermaking and is not effectively utilized. Conversion of industrial lignins into value-added materials is beneficial for the effective utilization of resources as well as for environmental protection. Because of their adsorptivity, slow-release property,biocompatibility, and biodegradability, lignin and its derivatives find potential applications as eco-friendly slow/controlled release materials in agricultural fields. This report reviews the recent research advances in lignin-based slow/controlled release fertilizers and pesticides. 展开更多
关键词 LIGNIN slow/controlled RELEASE FERTILIZER PESTICIDE
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Migration and Transformation of Coated Controlled Release Nitrogen in Soil under Co-situs Application Mode 被引量:11
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作者 肖强 王甲辰 +4 位作者 左强 张琳 刘宝存 赵同科 邹国元 《Agricultural Science & Technology》 CAS 2009年第6期144-149,共6页
By using field trials, the migration and transformation of coated controlled release nitrogen (YZS80) in soil under the co-situs application mode were studied. The results indicated that YZS80 nitrogen dissolved out... By using field trials, the migration and transformation of coated controlled release nitrogen (YZS80) in soil under the co-situs application mode were studied. The results indicated that YZS80 nitrogen dissolved out in average speed of about 0.4%/d and 32% totally in 80 d compared with common compound fertUizer. For YZS80, in the vertical downward direction of application points, urea nitrogen content increased significantly (P 〈0.05) in the 45 -80 d and the 30 -60 cm soil layers; nitrate nitrogen content was little change range and in moderate (10 -100 mg/kg) in 0 -80 d and 10 -60 cm soil layers, but increased significantly ( P 〈0.05) 45 -80 d compared to 0 -45 d; ammonium nitrogen content was significant lower (P〈0.05) before 45 d in 10 -30 cm soil layers, but significant higher(P〈0.05) after 45 d in 10 -60 cm soil layers; NO3^- -N/NH4^+ -N meets gradually the needs of the crop with the extension of time. Under the co-situs application mode, the possibility of burning root and salt injury and loss dsk of nitrate leaching is a significant reduction. 展开更多
关键词 Co-situs application slow/controlled release fertilizer MIGRATION TRANSFORMATION
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一总线在北京谱仪实验模型BESⅢ Slow Control中的应用 被引量:2
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作者 谢小希 谢嵩 +8 位作者 高翠山 聂振东 张银鸿 陈锡辉 刘国明 高路 谢一冈 Fabrizio Murtas Paolo Valente 《核电子学与探测技术》 CAS CSCD 北大核心 2005年第5期475-480,共6页
介绍了北京正负电子对撞机国家重点工程中,BESⅢS low Con tro l在全新北京谱仪中的重要性,并对通过在三个探测器:M uon RPC、量能器EM C、漂移室M DC实验模型中的具体实例应用,介绍了慢控制主要采用的一总线技术。
关键词 北京谱仪BESⅢ 慢控制 一总线 慢控制巡检仪
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BESIII Slow Control计算机系统结构与数据获取方案 被引量:1
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作者 谢小希 陈锡辉 +7 位作者 高翠山 谢嵩 刘国明 聂振东 张银鸿 闵建 闫学颖 谢一冈 《核电子学与探测技术》 CAS CSCD 北大核心 2006年第3期291-295,共5页
介绍了北京正负电子对撞机升级改进国家重点项目二期工程中,北京谱仪BESIII慢控制系统的微机系统结构及数据获取方案及系统软件设计。
关键词 北京谱仪BESⅢ 慢控制 一总线 USB LABVIEW
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Quantitative Evaluation on the Comprehensive Benefit of Controlled-Release Fertilizer in Typically Middle-Low Yield Rice Field
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作者 Qiankai TAN Xiaolong WU +4 位作者 Peilin ZHENG Cong FENG Tonghui LU Jianlei ZHENG Wenqi LI 《Agricultural Biotechnology》 CAS 2018年第3期126-132,共7页
Quantitative evaluation and analysis was made to the soil nutrients,rice yield,rice and fertilizer utilization rate,and economic and ecological benefits of the slow controlled release fertilizer in typical rice fields... Quantitative evaluation and analysis was made to the soil nutrients,rice yield,rice and fertilizer utilization rate,and economic and ecological benefits of the slow controlled release fertilizer in typical rice fields with middle-low yield by comparing the one-time application and split applications of slow-or controlledrelease fertilizer( CRF) with farmers fertilizer practice as the control,with the aim to explore the effect of CRF. Results showed that compared with the control,the application of CRF could meet balance nutrients required for rice growth,and the effective panicles and seed-setting rate were higher in the treatment groups of FVOL,SVOL,LADVOLwhich applied CRF. As for soil nutrients,soil pH maintained balance in FVOL,FCAI,SVOL,LADVOL. In addition,differences in soil nutrient reduction amount reached the extremely significant level between FVOLand SXNK.SVOLwhich applied CRF provided reasonable regulation of N,P and K release rate,which showed advantages over blending fertilization and farmers fertilizer practice. Comprehensive analysis found that the application of CRF could make rice tillering growth and decline leveled off,which effectively improved the quality of rice population,and it also had higher input-output ratio than that of the control and good economic benefits. In general,CRF suits to be used widely on rice crop in the regions with medium-low yield. 展开更多
关键词 RICE slow or controlled release fertilizer (CRF) Population quality Yield components
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Control Effect of Slow-release, Long-acting and Multi-functional New Pesticides on Sugarcane Borders and Woolly Aphids 被引量:1
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作者 Wenfeng LI Rongyue ZHANG +6 位作者 Xiaoyan WANG Hongli SHAN Jiong YIN Yonglei MAO Chao FANG Zhiming LUO Yingkun HUANG 《Agricultural Biotechnology》 CAS 2018年第6期97-100,共4页
In order to select the long-acting,low toxic,low-risk and multi-functional new pesticides for the control of sugarcane borders and woolly aphids and precise and efficient application technology,the control effect of 1... In order to select the long-acting,low toxic,low-risk and multi-functional new pesticides for the control of sugarcane borders and woolly aphids and precise and efficient application technology,the control effect of 10% monosultap · thiamethoxam granular formulation and 1% Bt · clothianidin granular formulation on sugarcane borders and woolly aphids were studied.The results showed that 10% monosultap·thiamethoxam GR and 1% Bt·clothianidin GR had good control effects on sugarcane borders and woolly aphids.They were ideal slow-release,long-acting,low toxic and multi-functional new pesticides used to control sugarcane borders and woolly aphids.They could be used alternately with other pesticides to delay the emergence and development of pest resistance to pesticides.The best dosage of the two pesticides in the field was 45 kg/hm^2.They could be mixed with fertilizer( 1200-1800 kg/hm^2),scattered in sugarcane ditches or at the base of sugarcane plants,and covered with soil or film from January to July.The control effect on dead heart seedlings damaged by borers could be up to above 79.2%,and the control effect on sugarcane woolly aphids could reach more than 98.8%.In comparison with the control group,the actual yield and sugar content of sugarcane increased by above 41 555 kg/hm^2 and 6.5% respectively.The application of slow-release,long-acting,strong systemic and multi-functional new agents with fertilizer around roots is convenient,precise and efficient,labor-saving,time-saving and environmentally friendly,and is worthy of being widely applied in sugarcane areas. 展开更多
关键词 slow-release and LONG-ACTING AGENTS PRECISE application of PESTICIDES SUGARCANE borders and woolly APHIDS control effect
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Slow driving control of tracked vehicles with automated mechanical transmission based on fuzzy logic
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作者 金辉 王军亮 苗成生 《Journal of Beijing Institute of Technology》 EI CAS 2015年第3期341-347,共7页
In order to move tracked vehicles at an extremely slowspeed with automated mechanical transmission( AMT),slowdriving function was added in the original system. The principle and requirement of slowdriving function w... In order to move tracked vehicles at an extremely slowspeed with automated mechanical transmission( AMT),slowdriving function was added in the original system. The principle and requirement of slowdriving function were analyzed. Based on analysis of slow driving characteristic,identification of slowdriving condition and fuzzy control algorithm,a control strategy of the clutch was designed. In order to realize slowdriving,the clutch was controlled in a slipping mode as manual driving. The vehicle speed was increased to a required speed and kept in a small range by engaging or disengaging the clutch to the approximate half engagement point. Based on the control strategy,a control software was designed and tested on a tracked vehicle with AMT. The test results showthat the control of the clutch with the slowdriving function was smoother than that with original systemand the vehicle speed was slower and steadier. 展开更多
关键词 slow driving automated mechanical transmission(AMT) fuzzy logic control strategy
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6-25 Progress of Slow Control Group in 2015
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作者 Wang Yanyu 《IMP & HIRFL Annual Report》 2015年第1期298-300,共3页
In 2015, through the efforts of all the members in Slow Control Group in IMP, we had got several good results in the HIRFL and the HIMM control, monitor and alarm system, such as the establishment of SFC extraction el... In 2015, through the efforts of all the members in Slow Control Group in IMP, we had got several good results in the HIRFL and the HIMM control, monitor and alarm system, such as the establishment of SFC extraction electrostatic deflector motion control system, the upgrade of the new kicker controller, the improvement of HIMM ion source and cyclotron control system, etc. Brief introductions of our major achievements are listed below. 展开更多
关键词 slow control GROUP
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TCP Window Based Congestion Control -Slow-Start Approach
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作者 Kolawole I. Oyeyinka Ayodeji O. Oluwatope +3 位作者 Adio. T. Akinwale Olusegun Folorunso Ganiyu A. Aderounmu Olatunde O. Abiona 《Communications and Network》 2011年第2期85-98,共14页
Transmission control protocol (TCP) has undergone several transformations. Several proposals have been put forward to change the mechanisms of TCP congestion control to improve its performance. A line of research tend... Transmission control protocol (TCP) has undergone several transformations. Several proposals have been put forward to change the mechanisms of TCP congestion control to improve its performance. A line of research tends to reduce speed in the face of congestion thereby penalizing itself. In this group are the window based congestion control algorithms that use the size of congestion window to determine transmission speed. The two main algorithm of window based congestion control are the congestion avoidance and the slow start. The aim of this study is to survey the various modifications of window based congestion control. Much work has been done on congestion avoidance hence specific attention is placed on the slow start in order to motivate a new direction of research in network utility maximization. Mathematical modeling of the internet is discussed and proposals to improve TCP startup were reviewed. There are three lines of research on the improvement of slow start. A group uses the estimation of certain parameters to determine initial speed. The second group uses bandwidth estimation while the last group uses explicit request for network assistance to determine initial startup speed. The problems of each proposal are analyzed and a multiple startup for TCP is proposed. Multiple startups for TCP specify that startup speed is selectable from an n-arry set of algorithms. We then introduced the e-speed start which uses the prevailing network condition to determine a suitable starting speed. 展开更多
关键词 Data Communication Network Protocols TCP CONGESTION control slow-Start (Keywords)
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缓控释肥硅基膜材的制备与表征
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作者 冯兆滨 吕真真 +5 位作者 冀建华 侯红乾 蓝贤瑾 刘益仁 刘淑珍 刘秀梅 《江西农业学报》 CAS 2024年第6期55-60,共6页
以钙镁磷肥、硅丙树脂为主要原料,加入甲基硅酸钠作粘结剂,制备了缓控释肥硅基膜材,并采用撒粉离心包衣、底喷式流化床工艺制备了密封型硅钙镁磷肥、粘结型硅钙镁磷肥、改性硅丙树脂3种包膜尿素,通过静水试验研究了此3种包膜尿素的释放... 以钙镁磷肥、硅丙树脂为主要原料,加入甲基硅酸钠作粘结剂,制备了缓控释肥硅基膜材,并采用撒粉离心包衣、底喷式流化床工艺制备了密封型硅钙镁磷肥、粘结型硅钙镁磷肥、改性硅丙树脂3种包膜尿素,通过静水试验研究了此3种包膜尿素的释放特征。结果表明,3种包膜尿素的释放周期分别为60、79、96 d,在水中均能保持完整球形,耐水性较好。通过扫描电镜、红外光谱、X-射线衍射法对膜材形貌特征和结构进行表征,发现钙镁磷肥和硅丙树脂为成膜材料;甲基硅酸钠作为密封剂和防水剂参与了成膜反应,有效增加了膜材的塑性和韧性,此复合材料可用作缓控释肥的胶结剂和包膜剂。 展开更多
关键词 缓控释肥料 硅基膜材 制备 表征
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袋控缓释铁肥提高梨树铁素利用率
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作者 孙文英 张守仕 +2 位作者 薛丽丰 乔宝营 刘荣宁 《湖北农业科学》 2024年第10期24-28,共5页
为探究袋控缓释铁肥改善梨树缺铁黄化的效果,采用硫酸亚铁与柠檬酸混合包装,并在肥料袋中添加生根诱导调节剂6-BA,设袋控缓释铁肥(HF)、撒施铁肥(SF)和不施铁肥(CK)3个处理,分析了其对梨树细根生长状况、叶片SPAD值以及叶片活性铁含量... 为探究袋控缓释铁肥改善梨树缺铁黄化的效果,采用硫酸亚铁与柠檬酸混合包装,并在肥料袋中添加生根诱导调节剂6-BA,设袋控缓释铁肥(HF)、撒施铁肥(SF)和不施铁肥(CK)3个处理,分析了其对梨树细根生长状况、叶片SPAD值以及叶片活性铁含量的影响。结果表明,HF梨树根系的细根最长、根体积和根表面积最大,其中在根长和根体积指标上显著高于SF和CK(P<0.05);HF和SF两处理在生长季内细根数量显著高于CK(P<0.05);HF肥效缓慢且稳定,持续维持一定的根系生物量,延长了梨树根系的褐变时间,其中HF褐变时间最长,为54 d,其次是SF,为43 d,CK为25 d,各处理间差异显著(P<0.05);HF显著提高了根系活力(P<0.05)。HF叶片SPAD值在7月和8月显著高于SF与CK(P<0.05)。8月各处理间梨树叶片活性铁含量差异显著(P<0.05),以HF的活性铁含量最高,为27.36 mg/kg。袋控缓释铁肥有效提高了梨树铁素利用率。 展开更多
关键词 梨树 袋控缓释铁肥 铁素利用率 根系生长 叶片SPAD值
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温度敏感型缓/控释肥料的温度响应特征、养分释放性能与温敏机理研究进展
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作者 李娟 杨相东 《植物营养与肥料学报》 CAS CSCD 北大核心 2024年第9期1812-1822,共11页
温度是影响缓/控释肥料养分释放特性的重要因素,开发温度敏感型缓/控释肥料可以使肥料养分释放与作物养分需求更加匹配,从而提高肥料利用效率,促进农业可持续发展。本文综述了聚酰胺类、聚醚类、聚酯类、多糖类以及温敏聚氨酯等常见的... 温度是影响缓/控释肥料养分释放特性的重要因素,开发温度敏感型缓/控释肥料可以使肥料养分释放与作物养分需求更加匹配,从而提高肥料利用效率,促进农业可持续发展。本文综述了聚酰胺类、聚醚类、聚酯类、多糖类以及温敏聚氨酯等常见的温敏聚合物材料的来源、类型和机理,详细阐述了聚N-异丙基丙烯酰胺(PNIPAM)、聚N-乙烯基己内酰胺(PNVCL)、环氧乙烷/环氧丙烷嵌段共聚物(EO/PO)、甲基纤维素和温敏聚氨酯等常见温敏聚合物材料用作温敏缓/控释肥料包膜材料的国内外研究进展,并评估了其在温敏缓/控释肥料中应用的可行性与优缺点。根据温敏特性,将温敏缓/控释肥料分为低临界溶解温度(LCST)响应型和结晶转变温度(Tm)/玻璃化转变温度(Tg)响应型两大类,并详细总结了这两种类型的制备方法、特征、养分释放性能以及分子作用机制。最后,指出温敏型缓/控释肥料的研发尚处于初级阶段,未来应深入开展天然高分子温敏材料的基础研究和创新,筛选绿色可生物降解温敏聚氨酯材料,研发作物和区域专用型温敏缓/控释肥料。 展开更多
关键词 温敏聚氨酯 缓/控释肥料 温度敏感型肥料 温度响应特征 养分释放机理
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缓/控释硫酸铵减量施用对玉米生长及土壤氮素平衡的影响
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作者 闫双堆 江慧姝 +5 位作者 董馨宇 张延慧 郭探文 韩莹 刘宇 闫秋艳 《核农学报》 CAS CSCD 北大核心 2024年第9期1772-1781,共10页
为筛选工业副产物—硫酸铵的最优处置措施,采用双因素裂区设计,主因素为施氮水平:常规施肥(C)、减量施肥(D);副因素为氮肥类型:尿素(U)、硫酸铵(AS)、缓/控释硫酸铵Ⅰ型(ASN、硫酸铵+硝化抑制剂)、缓/控释硫酸铵Ⅱ型(ASO、油脂包膜硫酸... 为筛选工业副产物—硫酸铵的最优处置措施,采用双因素裂区设计,主因素为施氮水平:常规施肥(C)、减量施肥(D);副因素为氮肥类型:尿素(U)、硫酸铵(AS)、缓/控释硫酸铵Ⅰ型(ASN、硫酸铵+硝化抑制剂)、缓/控释硫酸铵Ⅱ型(ASO、油脂包膜硫酸铵)、缓/控释硫酸铵Ⅲ型(ASH、油脂-腐植酸包膜硫酸铵),共10个处理,研究辅以不同增效措施后,硫酸铵施用对玉米(Zea mays L.)生长、氮吸收及土壤氮素平衡的影响。结果表明,减量施肥下,ASO处理的单穗重、穗长和植株干物质量均最高,分别较其他处理提高1.80%~30.29%、2.00%~13.91%和5.65%~24.21%。常规施肥下U处理玉米农艺性状指标高于其他氮肥类型处理。两种施氮水平下,缓/控释硫酸铵型施肥处理的有效穗数分别较其他处理提高5.36%~25.93%和9.82%~32.76%,以ASO处理最优,且其在减量施肥下的玉米叶片氮积累量显著高于其他处理;玉米产量则均以AS处理最低;ASH处理0~20 cm土层土壤各形态氮含量均显著高于其他氮肥类型,20~40 cm土层土壤碱解氮含量是其他处理的1.45~2.55倍;ASO处理20~40 cm土层土壤碱解氮、铵态氮含量均处于中等水平,说明ASO处理具有较好的缓/控释效果。所有氮肥类型在常规施肥下的表观氮损失均高于其减量施肥,且减量施肥下ASO处理的表观氮损失显著低于其他处理(U处理除外)。综上,与其他处理相比,减量施用油脂包膜硫酸铵可改善玉米农艺性状,显著提高玉米产量,降低土壤表观氮损失。本研究为推动工业副产硫酸铵的高效资源化利用提供了理论依据。 展开更多
关键词 硫酸铵 缓/控释 减施 产量 氮素平衡
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负载胰岛素的透明质酸温敏水凝胶的制备及体外释放评价
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作者 宣少燕 朱月 +3 位作者 唐志华 陈滕 陈智勇 汪祖华 《山东化工》 CAS 2024年第19期9-12,16,共5页
目的:制备负载胰岛素的透明质酸温敏水凝胶并对其进行初步评价。方法:通过酰肼交联反应得到己二酰肼/透明质酸,再利用自由基聚合法合成透明质酸温敏水凝胶;采用核磁共振氢谱对其进行结构确认,扫描电子显微镜观察其微观形态结构;采用紫... 目的:制备负载胰岛素的透明质酸温敏水凝胶并对其进行初步评价。方法:通过酰肼交联反应得到己二酰肼/透明质酸,再利用自由基聚合法合成透明质酸温敏水凝胶;采用核磁共振氢谱对其进行结构确认,扫描电子显微镜观察其微观形态结构;采用紫外分光光度法测定最低临界温度;以牛胰岛素作为模型药物,透明质酸温敏水凝胶作为递送载体,对其药物体外释放行为进行考察。结果:成功合成并制备了胰岛素装载的透明质酸温敏水凝胶。该水凝胶呈现三维网络类蜂窝结构,最低临界温度在30℃左右。体外释放结果显示,载药水凝胶在72 h内药物累积释放不到50%,而对照组在24 h内药物累积释放率几乎达到100%。结论:本研究所制备的透明质酸温敏水凝胶对胰岛素有一定的缓释作用,可作为大分子药物的递送载体。 展开更多
关键词 温敏水凝胶 药物缓控 透明质酸 胰岛素 体外释放
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基于阈值控制策略的Filippov Chay神经元动力学及其耦合同步
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作者 安新磊 任雁澜 《力学学报》 EI CAS CSCD 北大核心 2024年第4期1068-1087,共20页
细胞内外带电离子的连续泵送和传递产生的电磁感应效应对神经元的电活动及模态转换会产生一定的影响,促使其展现出更加丰富的放电特性.文章基于电磁感应影响下的Chay神经元模型,引入了一种以膜电压为阈值的不连续控制策略,建立了相应的F... 细胞内外带电离子的连续泵送和传递产生的电磁感应效应对神经元的电活动及模态转换会产生一定的影响,促使其展现出更加丰富的放电特性.文章基于电磁感应影响下的Chay神经元模型,引入了一种以膜电压为阈值的不连续控制策略,建立了相应的Filippov Chay神经元模型,探究了在阈值控制策略影响下的神经元放电节律转迁及相应的边界运动.首先,对系统的边界动力学及滑膜动力学进行了理论分析.其次,利用单双参数分岔图探究了系统多样的放电模式.再次,结合Matcont仿真及稳定性理论详细分析了系统的平衡点及其稳定性,并且利用快慢动力学分析法进一步研究了在阈值影响下所产生的滑膜动力学及各种边界运动的切换.最后,通过电突触耦合,对不同阈值条件下耦合神经元的同步问题进行了讨论.数值仿真结果表明,在阈值的调控下Filippov Chay系统会产生滑膜放电活动及相应的穿越运动和擦边运动,同时其放电周期数也会随着阈值呈现出不同的变化规律,且对于不同阈值下的电耦合情况而言,在系统实现完全同步后都会稳定在周期数较低的放电态.以上所得结果有助于更好地理解神经元滑膜的相关控制,对进一步探究生物神经系统中复杂放电活动和信息处理的动力学行为提供了一定的帮助. 展开更多
关键词 Filippov神经元 阈值控制 滑膜动力学 切换运动 快慢动力学分析 耦合同步
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不同缓/控释肥对玉米产量·经济效益及肥料利用率的影响 被引量:2
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作者 温国昌 李保军 +3 位作者 史明山 杨璞 范子洋 张娜娜 《安徽农业科学》 CAS 2024年第2期136-138,共3页
[目的]探究冀南平原玉米种植的缓/控释肥的应用效果。[方法]以邯玉398为材料,选取3种常见的玉米缓/控释复合肥进行田间试验,分析了不同类型缓/控释肥对玉米产量、经济效益及肥料利用率的影响。[结果]施用硫包衣缓/控释复合肥的玉米产量... [目的]探究冀南平原玉米种植的缓/控释肥的应用效果。[方法]以邯玉398为材料,选取3种常见的玉米缓/控释复合肥进行田间试验,分析了不同类型缓/控释肥对玉米产量、经济效益及肥料利用率的影响。[结果]施用硫包衣缓/控释复合肥的玉米产量、利润及农学利用效率较常规复合肥分别降低1.95%、3.27%、8.27%~31.21%;施用树脂包衣缓/控释复合肥的玉米产量提高0.65%,但利润、总养分量、磷、钾偏生产力和总养分量农学利用效率分别降低了1.45%、22.59%、49.67%、49.67%、20.09%;施用脲甲醛缓/控释复合肥的玉米产量、利润及总养分量偏生产力和农学利用效率较常规复合肥分别提高5.98%、5.50%、5.99%、25.22%,且产量、利润显著提高。[结论]综合分析,脲甲醛缓/控释复合肥可作为冀南平原玉米种植中的优先推荐。 展开更多
关键词 玉米 缓/控释肥 产量 经济效益 肥料利用率
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