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NARROW AND ROLLED LEAF 9,a Novel Gene Encoding 20S Proteasome β1 Subunit that Regulates Leaf Morphology and Grain Size in Rice
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作者 KANG Fengyu ZHOU Liang +4 位作者 CHEN Wenqiang# HUANG Pingliang Amos Musyoki MAWIA LUO Ju HU Peisong 《Rice science》 2025年第2期143-146,I0004-I0015,共16页
Rice leaf morphology is of great significance in the breeding of an ideal plant type and high photosynthetic efficiency.A forward genetics approach was employed to locate a novel gene,NRL9(NARROW AND ROLLED LEAF 9).NR... Rice leaf morphology is of great significance in the breeding of an ideal plant type and high photosynthetic efficiency.A forward genetics approach was employed to locate a novel gene,NRL9(NARROW AND ROLLED LEAF 9).NRL9 encodes a 20S proteasome β1 subunit and is involved in regulating leaf morphology and grain size.Compared with the wild type(WT),the nrl9 mutant exhibited a significant decrease in leaf width,and a significant increase in leaf rolling index(LRI),while also displaying increased grain length and decreased grain width. 展开更多
关键词 BREEDING GRAIN row
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Effect of Row Spacing Configuration Modes on Growth and Development of Xinluzao 63 and Amount of Residual Film in Agricultural Fields
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作者 Na LIU Wushiken +3 位作者 Honghao ZHANG Xia YAN Huzi CONG Lin LI 《Plant Diseases and Pests》 2025年第1期20-23,33,共5页
[Objectives]To provide a reference for the promotion of appropriate row spacing configuration modes for cotton planting in the Bortala Mongol Autonomous Prefecture of Xinjiang.[Methods]Xinluzao 63 was employed as the ... [Objectives]To provide a reference for the promotion of appropriate row spacing configuration modes for cotton planting in the Bortala Mongol Autonomous Prefecture of Xinjiang.[Methods]Xinluzao 63 was employed as the research subject to examine the effects of three different configuration modes:three rows with one film,four rows with one film,and six rows with one film,on the growth and development of cotton,as well as on yield and the amount of residual film in the field.[Results]In comparison to the configuration modes of four rows with one film and six rows with one film,the development process in the row spacing configuration mode of three rows with one film was accelerated by 1-4 d.This configuration mode exhibited variability in several agronomic traits,particularly in plant height,the number of fruiting branches per plant,and the number of leaves per plant,with the observed trend indicating T3>T2>T1.Conversely,the height of the first fruiting branch node displayed an inverse trend.In terms of yield composition,no significant differences were observed in boll weight and yield among various configuration modes.However,T3 exhibited the highest boll weight at 5.68 g and a yield of 462.67 kg/667 m 2.Additionally,significant differences were noted in harvesting density and the number of bolls per plant.T3 demonstrated the lowest harvesting density at 1.11×104 plants/666.7 m 2,the highest number of bolls per plant at 8.63,and the highest boll opening rate at 97.48%.Furthermore,T3 also resulted in the least amount of agricultural film residue during the current season.[Conclusions]Among the three planting configuration modes examined,the low-density planting configuration mode consisting of three rows and one film demonstrated a significant advantage at the individual plant level.This approach yielded results comparable to those of the high density planting configuration mode while also reducing costs.Furthermore,low density planting positively influenced the cotton boll opening rate,leading to a decreased amount of residual film and promoting ecological health within the agricultural land. 展开更多
关键词 COTTON row spacing configuration mode Growth and development YIELD Amount of residual film
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Mononuclear first-row transition-metal complexes as molecular catalysts for water oxidation 被引量:3
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作者 Ni Wang Haoquan Zheng +1 位作者 Wei Zhang Rui Cao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第2期228-244,共17页
Water oxidation is significant in both natural and artificial photosynthesis.In nature,water oxidation occurs at the oxygen‐evolving center of photosystem II,and leads to the generation of oxygen,protons,and electron... Water oxidation is significant in both natural and artificial photosynthesis.In nature,water oxidation occurs at the oxygen‐evolving center of photosystem II,and leads to the generation of oxygen,protons,and electrons.The last two are used for fixation of carbon dioxide to give carbohydrates.In artificial processes,the coupling of water oxidation to evolve O2and water reduction to evolve H2is known as water splitting,which is an attractive method for solar energy conversion and storage.Because water oxidation is a thermodynamically uphill reaction and is kinetically slow,this reaction causes a bottleneck in large‐scale water splitting.As a consequence,the development of new and efficient water oxidation catalysts(WOCs)has attracted extensive attention.Recent efforts have identified a variety of mononuclear earth‐abundant transition‐metal complexes as active and stable molecular WOCs.This review article summarizes recent progress in research on mononuclear catalysts that are based on first‐row transition‐metal elements,namely manganese,iron,cobalt,nickel,and copper.Particular attention is paid to catalytic mechanisms and the key O?O bond formation steps.This information is critical for designing new catalysts that are highly efficient and stable. 展开更多
关键词 Water oxidation O-O bond formation Oxygen evolution firstrow transition metal ELECTROCATALYSIS
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Recent advances of allenes in the first-row transition metals catalyzed C-H activation reactions 被引量:1
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作者 Xiang-Lei Han Peng-Peng Lin Qingjiang Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第8期1495-1502,共8页
Transition-metal-catalyzed C–H activation reaction has proven to be a powerful and efficient tool for the formation of diverse C-C and C–X bond and construction of functional complex molecules.From the viewpoint of ... Transition-metal-catalyzed C–H activation reaction has proven to be a powerful and efficient tool for the formation of diverse C-C and C–X bond and construction of functional complex molecules.From the viewpoint of sustainable chemistry,the first-row transition metals,such as Mn,Fe,Co,Ni and Cu,have been recognized as cheap,environmentally friendly and reactively effective catalysts for a number of C-H functionalization reactions.However,compared with the commonly used alkenes and alkynes in the first-row transition-metal-catalyzed C–H activations,considerable achievements have just been made by the use of structurally unique and reactively rich allenes as coupling partners in recent years.This review summarizes the recent progress of the first-row transition-metal-catalyzed C–H activations with allenes. 展开更多
关键词 ALLENE C-H FUNCTIONALIZATION first-row transition metal ANNULATION Regioselectivity
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Effects of mesoclimate and microclimate variations mediated by high altitude and row orientation on sucrose metabolism and anthocyanin synthesis in grape berries 被引量:2
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作者 Haining Yin Zhaoxiang Wang +3 位作者 Lin Wang Jianhong Cao Jiakui Wang Zhumei Xi 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期713-731,共19页
Climate change and extreme weather pose significant challenges to the traditional viticulture regions.Emerging high-altitude grape-producing regions with diverse orientations have shown great potential in coping with ... Climate change and extreme weather pose significant challenges to the traditional viticulture regions.Emerging high-altitude grape-producing regions with diverse orientations have shown great potential in coping with this challenge.Stable,high-quality wine grape production may be achieved by synchronizing the meso-and microclimate.To clarify the role of high altitude and row orientation in meso-and microclimate and the response of berries to it,we evaluated seven years(2012-2018)of climate data,two years of basic grape(Cabernet Sauvignon,Vitis vinifera L.)quality,and one-year microclimate from veraison to harvest.By comparing two locations(Sidon 2047 m,Sinon 2208 m)in Yunnan Province,China,we found that the average temperature has been stable at approximately 15℃ for seven years,with no extreme weather or,noticeable global warming.The light intensity(LI)in the north-south(NS)was more balanced than the east-west(EW)direction,and the east-west to the south(EW-S)canopy side was almost higher than the other sides.High LI was associated with high photosynthetically active radiation(PAR),ultraviolet(UV),and infrared(IR)light and vice versa.The north-south to the east(NS-E)and east-west to the north(EWN)sides were characterized by lower LI and higher UV and IR light,and higher total anthocyanin content.Most anthocyanin synthesis-related genes,for example,VvF3'H and VvF3'5'H,were highly expressed in NS-E from veraison to maturity.Perhaps UV and IR light induced their expression.This study provides new insights on the role of differently orientated rows in controlling grape quality due to varied light quality.The findings are globally significant,particularly in the context of climate change,and offer fresh insights into berry physiological responses and decision-making for the management of existing vineyards. 展开更多
关键词 Vitis vinifera L. Orientated rows Berry composition SUGAR PHENOLIC Light quality Solar radiation
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A Two-Stage Scenario-Based Robust Optimization Model and a Column-Row Generation Method for Integrated Aircraft Maintenance-Routing and Crew Rostering
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作者 Khalilallah Memarzadeh Hamed Kazemipoor +1 位作者 Mohammad Fallah Babak Farhang Moghaddam 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第11期1275-1304,共30页
Motivated by a critical issue of airline planning process,this paper addresses a new two-stage scenario-based robust optimization in operational airline planning to cope with uncertainty and possible flight disruption... Motivated by a critical issue of airline planning process,this paper addresses a new two-stage scenario-based robust optimization in operational airline planning to cope with uncertainty and possible flight disruptions.Following the route network scheme and generated flight timetables,aircraft maintenance routing and crew scheduling are critical factors in airline planning and operations cost management.This study considers the simultaneous assignment of aircraft fleet and crew to the scheduled flight while satisfying a set of operational constraints,rules,and regulations.Considering multiple locations for airline maintenance and crew bases,we solve the problem of integrated Aircraft Maintenance Routing and Crew Rostering(AMRCR)to achieve the minimum airline cost.One real challenge to the efficiency of the planning results is the possible disruptions in the initial scheduled flights.Due to the fact that disruption scenarios are expressed discretely with a specified probability,and we provide adjustable decisions under disruption to deal with this disruption risk,we provide a Two-Stage Scenario-Based Robust Optimization(TSRO)model.In this model,here-and-now or first-stage variables are the initial resource assignment.Furthermore,to adapt itself to different disruption scenarios,the model considers some adjustable variables,such as the decision to cancel the flight in case of disruption,as wait-and-see or second-stage variables.Considering the complexity of integrated models,and the scenario-based decomposable structure of the TRSO model to solve it with better computational performance,we apply the column and row generation(CRG)method that iteratively considers the disruption scenarios.The numerical results confirm the applicability of the proposed TSRO model in providing the AMRCR problem with an integrated and robust solution with an acceptable level of computational tractability.To evaluate the proposed TSRO model,which solves the AMRCR problem in an integrated and robust manner,five Key Performance Indicators(KPIs)like Number of delayed/canceled flights,Average delay time,and Average profit are taken into account.As key results driven by conducting a case study,we show the proposed TSRO model has substantially improved the solutions at all indicators compared with those of the sequential/non-integrated and nominal/non-robust models.The simulated instances used to assess the performance of the proposed model and CRG method reveal that both CPLEX and the CRG method exhibit comparable and nearly optimal performance for small-scale problems.However,for large-scale instances the proposed TSRO model falls short in terms of computational efficiency.Conversely,the proposed CRG method is capable of significantly reducing computational time and the optimality gap to an acceptable level. 展开更多
关键词 Aircraft maintenance routing crew scheduling ROSTERING uncertainty scenario-based robust optimization column and row generation
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A Theoretical Study of Tris-(o-benzoquinonediimine)-First-Row Divalent Transition Metal Complexes
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作者 Mohammad Abdul Matin Samiran Bhattacharjee Anwar Hossain 《Advances in Chemical Engineering and Science》 CAS 2023年第2期172-188,共17页
The ligand o-phenylenediamine (opda) and its oxidized form, o-benzoquinonediimine (bqdi), act as a fascinating candidate coordinating toward transition metal ions leading to the photochemical hydrogen production in ab... The ligand o-phenylenediamine (opda) and its oxidized form, o-benzoquinonediimine (bqdi), act as a fascinating candidate coordinating toward transition metal ions leading to the photochemical hydrogen production in absence of photosensitizers. Herein, we report the systematic study of the interaction between the oxidized form bqdi ligand, tris-(o-benzoquinonediimine) with divalent first-row transition metal series using DFT calculations. The lowest energy structures, bond length, binding energies, frontier molecular orbital analysis, natural bond orbitals, and global reactivity descriptor were calculated using B3LYP/6-311G(d,P) level of theory. The time dependent-DFT at the CAM-B3LYP/6-311+G(d,p) level of theory was applied to determine the electronic structures and the optical spectra. The theoretical binding trend of the divalent first-row transition metal series is decreasing as follows: Cu >Ti > V > Co > Ni > Fe > Cr > Zn >Mn. Among them, the binding potency of iron (II) by the bqdi ligand was not predominantly sturdy as compared to other first-row divalent transition metal ions. The origin of strong coordination with Fe(II) is attributed to its extra capability to induce covalent coordination of bqdi ligands. The complex exhibited two strong peaks at 370 nm and 452 nm, due to the HOMO-3 to LUMO+1 and HOMO-1 to LUMO transitions, respectively. Natural bond orbital analysis showed that the major interaction happens between the N lone pair electrons of the ligand with an anti-bonding orbital of metal ions, in which Ti showed the highest interaction energy than other metal ions. The present systemic DFT study of bqdi ligands with the first-row transition metals strongly encourages the future establishment of photochemical hydrogen production in absence of photosensitizers. 展开更多
关键词 DFT O-PHENYLENEDIAMINE o-benzoquinodiimine first-row Divalent Transition Metals Time Dependent–DFT Coordination Complexes
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Inter-Row Spacing of PV Power Plant
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作者 Laiqat Ali Khan 《Energy and Power Engineering》 2024年第3期121-129,共9页
When designing a solar power plant, it is much more important to avoid the shadow on the PV Panels. As the shadow falls on the PV Panels;it significantly reduces the generation of required power as planned and designe... When designing a solar power plant, it is much more important to avoid the shadow on the PV Panels. As the shadow falls on the PV Panels;it significantly reduces the generation of required power as planned and designed. This research paper and case study will help a lot to avoid shadow, especially when selecting inter-row spacing between the strings of solar power plants. 展开更多
关键词 Inter row Spacing Shadow Effect on PV Plant Hot Spot Heating
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Rediscovering Determinant Expansion on Row or Column Theorem Through Plausible Reasoning
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作者 Haiyan Liu 《Journal of Contemporary Educational Research》 2024年第12期121-126,共6页
Plausible reasoning is an important approach to reasoning conclusions.In order to cultivate students’habits and abilities to use plausible reasoning,we should give the students a chance to imitate and practice plausi... Plausible reasoning is an important approach to reasoning conclusions.In order to cultivate students’habits and abilities to use plausible reasoning,we should give the students a chance to imitate and practice plausible reasoning in our teaching.For our linear algebra course,most of the definitions and theorems in popular linear algebra textbooks are given directly.Thus,we give a concrete process that rediscovers determinant expansion on row or column theorem through plausible reasoning during our teaching to give the students the chance to learn the reasoning. 展开更多
关键词 Determinant expansion on row or column theorem Plausible reasoning
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堆石体修正Rowe剪胀方程与南水模型 被引量:47
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作者 张丙印 贾延安 张宗亮 《岩土工程学报》 EI CAS CSCD 北大核心 2007年第10期1443-1448,共6页
在分析堆石体三轴试验成果的基础上,探讨了堆石体的体积变形特性,提出了形式简洁的堆石体修正Rowe剪胀方程。将所建立的修正Rowe剪胀方程引入到沈珠江院士提出的"南水模型",克服了该模型由于采用体变–轴向应变抛物线假设所... 在分析堆石体三轴试验成果的基础上,探讨了堆石体的体积变形特性,提出了形式简洁的堆石体修正Rowe剪胀方程。将所建立的修正Rowe剪胀方程引入到沈珠江院士提出的"南水模型",克服了该模型由于采用体变–轴向应变抛物线假设所带来的一些缺陷。应用堆石体常规三轴试验和典型复杂应力路径三轴试验成果对修正后模型的合理性进行了验证。 展开更多
关键词 堆石料 rowe剪胀方程 双屈服面弹塑性模型
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Effects of Ratio of Row Spacing to Intrarow Spacing on Yield and Top Three Leaves of Super High-yielding Early and Late Rice 被引量:2
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作者 林洪鑫 彭春瑞 +5 位作者 雷享亮 袁展汽 肖运萍 刘仁根 胡启锋 张结刚 《Agricultural Science & Technology》 CAS 2014年第1期52-56,101,共6页
Using a split plot design, super high-yielding early rice &quot;Zhongjiazao 17&quot;and &quot;Ganxin 203&quot; and super high-yielding late rice &quot;Ganxin 688&quot; and &quot;Wufengy-ouT025&quot; were taken... Using a split plot design, super high-yielding early rice &quot;Zhongjiazao 17&quot;and &quot;Ganxin 203&quot; and super high-yielding late rice &quot;Ganxin 688&quot; and &quot;Wufengy-ouT025&quot; were taken as materials with planting density the same at 312 000 hil s/hm2, to explore the effects of RS/IS (Ratio of row spacing to intrarow row spacing) on yield, top three leaves morphological features and its relationship of them in 2011 and 2012. The results showed that, whether early or late rice, biomass, accumula-tion and apparent utilizing rate of nitrogen were lower in RS/IS5.0 (40.0 cm &#215;8.0 cm) treatment, but yield of rice was higher in RS/IS2.0 (25.0 cm &#215;12.8 cm) treatment;grain numbers per spike of rice was more in RS/IS2.8 (30.0 cm&#215;10.7 cm) treatment, and thousand-grain weight of rice was higher in RS/IS1.3 (20.0 cm&#215;16.0 cm) treat-ment. For 4 varieties of early or late rice aforementioned, basal angle, opening an-gle and leaf area of 2nd leaf from top were larger in RS/IS5.0 treatment, and basal angle and opening angle were smal er in RS/IS2.0 treatment and leaf area smal er in RS/IS1.3 treatment. 展开更多
关键词 Super high-yielding early and late rice Ratio of row spacing to intrarowspacing Top three leaves Leaf morphology
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Bell不等式实验检验的重大进展——Weihs实验和Rowe实验述评 被引量:1
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作者 黄政新 《南京理工大学学报(社会科学版)》 2010年第4期45-50,共6页
Weihs实验(1998)和Rowe实验(2001)可能是自Aspect实验(1982)以来已完成的几十个Bell型实验中最重要的两个。这两个实验已分别地封闭了定域性漏洞和效率漏洞,但定域隐变量理论并没有完全被排除。相信有朝一日人们会完成一个无漏洞的实验... Weihs实验(1998)和Rowe实验(2001)可能是自Aspect实验(1982)以来已完成的几十个Bell型实验中最重要的两个。这两个实验已分别地封闭了定域性漏洞和效率漏洞,但定域隐变量理论并没有完全被排除。相信有朝一日人们会完成一个无漏洞的实验。即使如此,定域隐变量理被排除的问题仍然会是悬而未决的。断言试图通过完成一个无争议的判决性实验来解决定域隐变量理论与量子力学的冲突是不可能的。 展开更多
关键词 Weihs实验 rowe实验 BELL不等式 定域性漏洞 效率漏洞
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Therapy of auricular subcutaneous penetration needling combined with row acupuncture at the meridian sinew in 103 cases of prolapse of lumbar intervertebral disc
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作者 侯献兵 刘英莉 +3 位作者 王利春 卢威威 宋书昌 贾春生 《World Journal of Acupuncture-Moxibustion》 CSCD 2015年第2期63-66,共4页
Objective To observe the clinical efficacy of auricular subcutaneous penetration needling combining with row acupuncture at meridian sinew on prolapse of lumbar intervertebral disc. Methods One hundred and three patie... Objective To observe the clinical efficacy of auricular subcutaneous penetration needling combining with row acupuncture at meridian sinew on prolapse of lumbar intervertebral disc. Methods One hundred and three patients with prolapse of lumbar intervertebral disc were treated with a combined treatment of auricular subcutaneous penetration needling and row acupuncture at meridian sinew. Results Of 103 patients, 46 cases were cured, 33 were markedly effective, 21 effective and 3 ineffective. The total effective rate was 97.1% (100/103). Conclusion The combined treatment of auricular subcutaneous penetration needling and row acupuncture at meridian sinew has a significant efficacy for the treatment of prolapse of lumbar intervertebral disc. 展开更多
关键词 prolapse of lumbar intervertebral disc auricular subcutaneouspenetration needling row acupuncture at meridian sinew
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Row Fixation - A Parallel Algorithm for Matrix Computing
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作者 沈文枫 郁松年 徐炜民 《Advances in Manufacturing》 SCIE CAS 2000年第S1期119-122,共4页
Row fixation is a parallel algorithm based on MPI that can be implemented on high performance computer system. It keeps the characteristics of matrices since row-computations are fixed on different nodes. Therefore t... Row fixation is a parallel algorithm based on MPI that can be implemented on high performance computer system. It keeps the characteristics of matrices since row-computations are fixed on different nodes. Therefore the locality of computation is realized effectively and the acceleration ratio is obtained very well for large scale parallel computations such as solving linear equations using Gaussian reduction method, LU decomposition of matrices and m-th power of matrices. 展开更多
关键词 row fixation MPI SMP augmented matrix speedup ratio
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Effects of Planting Density and Row Spacing on Grass Yield of Forage Sweet Sorghum(Sorghum bicolor [L.]Moench)
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作者 周汉章 刘环 +4 位作者 贾海燕 魏志敏 袁淑红 侯升林 李顺国 《Agricultural Science & Technology》 CAS 2017年第12期2345-2353,2371,共10页
[Objective] The aim was to explore high-yielding cultivation techniques for forage sweet sorghum. [Method[ The effects of planting density and row spacing on plant productivity and grass yield of forage sweet sorghum ... [Objective] The aim was to explore high-yielding cultivation techniques for forage sweet sorghum. [Method[ The effects of planting density and row spacing on plant productivity and grass yield of forage sweet sorghum (Sorghum bicolor (L.) Moench) were compared using split-plot design and LSD method of IBMSPSSStatis- ticsv22. [Result]The planting density and row spacing had important influence on the plant productivity and yield of forage sweet sorghum. The optimum planting density- row spacing combination for plant productivity of forage sweet sorghum was A1B,, i. e., planting density of 75 000 plants/hm2 and row spacing of 40 cm, and the opti- mum combination for yield of forage sweet sorghum was A2B,, i.e., planting density of 225 000 plants/hm2 and row spacing of 40 cm. [Conclusion] This study will pro- vide theoretical basis and technical support for the production practice of forage sweet sorghum. 展开更多
关键词 Forage sweet sorghum Planting density row spacing Grass yield
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Light Simplified Cultivation Techniques of Wide Row and Double Ridge with Filming, Fertilizing and Sowing on One for Foxtail Millet
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作者 夏雪岩 刘猛 +6 位作者 杜钟 宋世佳 赵宇 刘斐 任晓利 南春梅 李顺国 《Agricultural Science & Technology》 CAS 2016年第3期563-565,共3页
In view of the problems of completely depending on rain, low and unstable yield and complicated planting of dry land foxtail millet, the light simplified cultivation techniques of wide row and double ridge with filmin... In view of the problems of completely depending on rain, low and unstable yield and complicated planting of dry land foxtail millet, the light simplified cultivation techniques of wide row and double ridge with filming, fertilizing and sowing on one for foxtail millet was formed through the integration of plastic film mulching technology and mechanized production technology by Institute of Millet crops of Hebei Academy of Agriculture and Forestry Sciences, and the techniques were introduced from the key technologies of pre-sowing preparation, sowing, supporting equipment, field management, harvesting, plastic film recycling. 展开更多
关键词 Foxtail millet Wide row and double ridge cultivation Filming and fertilizing Light simplified cultivation techniques
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朝永-Rowe理论作为原子核代数模型的基础
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作者 周孝谦 《核技术》 CAS CSCD 北大核心 1989年第8期494-497,共4页
将Rowe的Sp(6)核集体运动模型以两种方法嵌入较大的李代数。分别以费米子和玻色子为基础。两种方法得到的大的李代数都有丰富的约化群链。它们分别与FDSM和IBM相应。
关键词 原子核 代数模型 rowe理论 约化群
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第一过渡周期金属参与的光催化反应研究进展
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作者 郭福虎 孙志凡 +1 位作者 丁蓓 樊新元 《新兴科学和技术趋势》 2025年第2期129-145,共17页
近年来,可见光介导的第一过渡周期金属催化在有机合成中展现出巨大的潜力。与传统的贵金属光催化剂(如铱和钌)相比,第一过渡周期金属(如铁、铜和钴)以其廉价和丰富的特点,正在推动绿色化学的研究。尽管第一过渡周期金属配合物的光激发... 近年来,可见光介导的第一过渡周期金属催化在有机合成中展现出巨大的潜力。与传统的贵金属光催化剂(如铱和钌)相比,第一过渡周期金属(如铁、铜和钴)以其廉价和丰富的特点,正在推动绿色化学的研究。尽管第一过渡周期金属配合物的光激发态寿命比铑和铱光催化剂要短,但可以通过合理设计配体有效地提高其光催化活性。可见光介导的第一过渡周期金属催化主要有两种反应路径:(1)激发态的第一过渡周期金属配合物发生配体-金属电荷转移(LMCT)过程产生自由基活性物种参与反应;(2)激发态的第一过渡周期金属配合物与底物分子之间发生单电子转移(SET)过程产生活性物种参与反应。本文主要概述以第二种反应路径催化有机转化的近五年的研究进展。 展开更多
关键词 可见光催化 第一过渡周期金属 光催化反应 激发态
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Effect of meridian sinew row needling combined with dermal needling on spasticity of post-stroke patients with upper limb hemiparalysis: a multi-center randomized controlled trial 被引量:3
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作者 韩淑凯 郝海燕 +3 位作者 刘风辉 李卿 李学飞 杨伟红 《World Journal of Acupuncture-Moxibustion》 CSCD 2015年第1期13-18,共6页
Objective To explore the effect of meridian sinew row needling combined with dermal needling on spasticity of post-stroke patients with upper limb hemiparalysis. Methods Four hundred and eighty-eight cases of post-str... Objective To explore the effect of meridian sinew row needling combined with dermal needling on spasticity of post-stroke patients with upper limb hemiparalysis. Methods Four hundred and eighty-eight cases of post-stroke patients with upper limb spasticity were randomly divided into two groups at the ratio of 1: 1, the group of meridian sinew row needling combined with dermal needling (group A, 244 cases) and western medication group (group B, 244 cases). Coupled with rehabilitation, the patients in the group A were given meridian sinew row needling combined with dermal needling where five shu points were specifically selected, and three yang meridians of the hand were treated with acupuncture with muscle region, and three yin meridians of the hand were treated with dermal needles; the patients in the group B was treated with conventional western medication with piracetam injection and cerebroprotein hydrolysate included. Clinical efficacy was evaluated among patients in the two groups after three weeks of continuous treatment, and upper limb spasticity and motor functions were observed through modified Asworth Scale and FugI-Meyer Assessment Scale (FMA) before and after treatment. Results For Asworth Scale, group A was significantly superior to group B (3.04 ± 1.29 vs 3.88 ± 1.54, P〈0.05); for FMA scale, group A was also significantly superior to group B (48.67± 15.64 vs 42.96±14.72, P〈0.05); mitigations of motor status of upper limb joints in group A, such as remission of shoulder adduction (90.5%), pronation of forearm (70.7%), elbow joint flexion (73.1%), wrist joint flexion (80.9%) and finger flexion (88.1%), were superior to those of group B (70.0%, 60.0%, 61.9%, 57.4%, 63.2%, all P〈0.05). Conclusion Good clinical efficacy of the treatment with combined with dermal needling on spasticity of post-stroke patients with upper limb hemiparalysis is achieved. 展开更多
关键词 meridian sinew row needling dermal needling spasticity upper limbs stroke sequelae multi-center randomized controlled trial (RCT)
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Effect of wide-narrow row arrangement in mechanical pot-seedling transplanting and plant density on yield formation and grain quality of japonica rice 被引量:33
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作者 HU Qun JIANG Wei-qin +7 位作者 QIU Shi XING Zhi-peng HU Ya-jie GUO Bao-wei LIU Guo-dong GAO Hui ZHANG Hong-cheng WEI Hai-yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第5期1197-1214,共18页
Mechanical pot-seedling transplanting is an innovatively developed transplanting method that has the potential to replace mechanical carpet-seedling transplanting. However, the initial pot-seedling transplanting machi... Mechanical pot-seedling transplanting is an innovatively developed transplanting method that has the potential to replace mechanical carpet-seedling transplanting. However, the initial pot-seedling transplanting machine lacked optimized density spacing and limited yield potential for japonica rice. Therefore, ascertaining the optimized density by wide-narrow rows and the appropriate transplanting method for yield formation and grain quality of japonica rice is of great importance for high-quality rice production. Field experiments were conducted using two japonica rice cultivars Nanjing 9108 and Nanjing 5055 under three transplanting methods in 2016 and 2017: mechanical pot-seedling transplanting with wide-narrow row(K, average row spacing of 30 cm);equidistant row(D, 33 cm×12 cm);and mechanical carpet-seedling transplanting(T, 30 cm×12.4 cm). In addition, five different density treatments were set in K(K1–K5, from 18.62×10~4 to 28.49×10~4 hills ha^(–1)). The results showed that the highest yield was produced by a planting density of 26.88×104 hills ha^(–1) in mechanical pot-seedling transplanting with wide-narrow row with a greater number of total spikelets that resulted from significantly more panicles per area and slightly more grain number per panicle, as compared with equidistant row, and yield among density in wide-narrow row showed a parabolic trend. Compared with mechanical carpet-seedling transplanting, the treatment of the highest yield increased yield significantly, which was mainly attributed to the larger sink size with improved filled-grain percentage and grain weight, higher harvest index, and increased total dry matter accumulation, especially the larger amount accumulated from heading stage to maturity stage. With the density in wide-narrow row decreasing, processing quality, appearance quality, and nutrition quality were all improved, whereas amylose content and the taste value were decreased. Compared with mechanical carpet-seedling transplanting, mechanical pot-seedling transplanting improved processing quality and nutrition quality, but decreased amylose content and deteriorated appearance quality. These results suggested that mechanical pot-seedling transplanting with wide-narrow row coupling produced a suitable planting density of 26.88×10~4 hills ha^(–1) and may be an alternative approach to improving grain yield and quality for japonica rice. 展开更多
关键词 density grain quality JAPONICA rice TRANSPLANTING methods wide-narrow row yield formation
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