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GENERALIZED FORELLI-RUDIN TYPE OPERATORS BETWEEN SEVERAL FUNCTION SPACES ON THE UNIT BALL OF C^(N)
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作者 Xuejun ZHANG Yuting GUO +1 位作者 Hongxin CHEN Pengcheng TANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1301-1326,共26页
In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order t... In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order to prove the main results,we first give some bidirectional estimates for several typical integrals. 展开更多
关键词 Forelli-Rudin type operator L^(p q s k)(B_(n))space BOUNDEDNESS unit ball
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Ability of Ectomycorrhizal FUngus Laccaria biclor S238N to Increase the Growth of Douglas FIr Seedlings and Their Phosphorus and Potassium Uptake 被引量:19
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作者 HUANGJIANGUO F.LAPEYRIE 《Pedosphere》 SCIE CAS CSCD 1996年第3期217-224,共8页
Ectomycorrhizal fungus Laccaria bicolor S238N,isolated from a forest soil in central France in 1990s,has demonstrated unequivocally and ability to promote pine growth.In the present nursery bed experiment,the ability ... Ectomycorrhizal fungus Laccaria bicolor S238N,isolated from a forest soil in central France in 1990s,has demonstrated unequivocally and ability to promote pine growth.In the present nursery bed experiment,the ability of this ectomycorrhizal fungus to increase growth and P and K uptake of Douglas Fir seedlings (Zone 22) was examined.Growth of inoculated seedlings was over twice(plant height) and three times (biomass)that of non-inoculated ones.Similarly,both the concentrations and the amounts of P and K uptake by seedlings were significantly increased by fungal inoculation,indicating the improvement of P and K nutrition in mycorrhizal seedlings.In contrast,Al-P in the soils was decreased obviously by plants,especially by mycorrhizas,suggesting utilization of this soil P pool by plants and more efficient Al-P mobilization by mycorrhizas than by nomycorrhizas.Moreover,K extracted by 1mol/L HCl following consecutive extraction of H2O and CH3COONH4,which may not be plant available,could be utilized by fungus colonied roots.This could be explained by the release of protons and oxalate by hypae which leads to replacement of interlayer K in nonexpanded 2:1 clay minerals and bio-weathering of phyllosilicates. 展开更多
关键词 外生菌根真菌 黄杉树苗 P吸收 K吸收 促生长作用 S238N
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The Growth Characteristics of Three Terrestrial Plants Cultivated with Biogas Slurry as a Hydroponic Medium
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作者 Qun Kang Jinhui Zhao +3 位作者 Pan Zhu Qin Gong Ling Wang Zhaohua Li 《American Journal of Plant Sciences》 2020年第6期819-831,共13页
Biogas slurry is a traditional high-quality organic liquid fertilizer. Three terrestrial plants with high economic value, fu </span><span style="font-family:Verdana;">gui</span> <span st... Biogas slurry is a traditional high-quality organic liquid fertilizer. Three terrestrial plants with high economic value, fu </span><span style="font-family:Verdana;">gui</span> <span style="font-family:Verdana;">cai</span><span style="font-family:Verdana;">, yang </span><span style="font-family:Verdana;">xin</span> <span style="font-family:Verdana;">cai</span> <span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> strawberry, were selected for hydroponic cultivation using an optimal dilution of biogas slurry. The results of the experiments showed that strawberries could bloom and bear fruit and fu </span><span style="font-family:Verdana;">gui</span> <span style="font-family:Verdana;">cai</span><span style="font-family:Verdana;"> and yang </span><span style="font-family:Verdana;">xin</span> <span style="font-family:Verdana;">cai</span><span style="font-family:Verdana;"> grew well. However, in comparison with the control groups planted in soil, all three crops were subject to a certain degree of environmental stress, as shown by changes in growth, biomass indicators, physiological indicators </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> morphological indicators. The leaves and stems of yang </span><span style="font-family:Verdana;">cai</span><span style="font-family:Verdana;"> and fu </span><span style="font-family:Verdana;">gui</span> <span style="font-family:Verdana;">cai</span><span style="font-family:Verdana;"> were tested for several types of heavy metals, and all met the requirements for human consumption. It is feasible to cultivate these three plants with biogas slurry. The results of this study can help guide hydroponic production practices and have practical significance and reference value. 展开更多
关键词 Biogas Slurry Fu Gui Cai Yang Xin Cai STRAWBERRY N/P/K Vitamin C CHLOROPHYLL Heavy Metals
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The Generalization of Signed Domination Number of Two Classes of Graphs
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作者 Xia Hong Guoyan Ao Feng Gao 《Open Journal of Discrete Mathematics》 2021年第4期114-132,共19页
Let <img src="Edit_092a0db1-eefa-4bff-81a0-751d038158ad.png" width="58" height="20" alt="" /> be a graph. A function <img src="Edit_b7158ed5-6825-41cd-b7f0-5ab5e16... Let <img src="Edit_092a0db1-eefa-4bff-81a0-751d038158ad.png" width="58" height="20" alt="" /> be a graph. A function <img src="Edit_b7158ed5-6825-41cd-b7f0-5ab5e16fc53d.png" width="79" height="20" alt="" /> is said to be a Signed Dominating Function (SDF) if <img src="Edit_c6e63805-bcaa-46a9-bc77-42750af8efd4.png" width="135" height="25" alt="" /> holds for all <img src="Edit_bba1b366-af70-46cd-aefe-fc68869da670.png" width="42" height="20" alt="" />. The signed domination number <img src="Edit_22e6d87a-e3be-4037-b4b6-c1de6a40abb0.png" width="284" height="25" alt="" />. In this paper, we determine the exact value of the Signed Domination Number of graphs <img src="Edit_36ef2747-da44-4f9b-a10a-340c61a3f28c.png" width="19" height="20" alt="" /> and <img src="Edit_26eb0f74-fcc2-49ad-8567-492cf3115b73.png" width="19" height="20" alt="" /> for <img src="Edit_856dbcc1-d215-4144-b50c-ac8a225d664f.png" width="32" height="20" alt="" />, which is generalized the known results, respectively, where <img src="Edit_4b7e4f8f-5d38-4fd0-ac4e-dd8ef243029f.png" width="19" height="20" alt="" /> and <img src="Edit_6557afba-e697-4397-994e-a9bda83e3219.png" width="19" height="20" alt="" /> are denotes the <em>k</em>-th power graphs of cycle <img src="Edit_27e6e80f-85d5-4208-b367-a757a0e55d0b.png" width="21" height="20" alt="" /> and path <img src="Edit_70ac5266-950b-4bfd-8d04-21711d3ffc33.png" width="18" height="20" alt="" />. 展开更多
关键词 Signed Domination Function Signed Domination Numbers Graphs Cn style="margin-left:-7px ">k Graphs Pn style="margin-left:-7px ">k
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The Effects of Legume Crops (Pea and Faba Bean) on Soil Nutrients Availability and Yield Parameters of Subsequent Cabbage Crops under Organic Production Conditions
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作者 Glenda Sallaku Josif Liko +1 位作者 Zamira Rada Astrit Balliu 《Journal of Environmental Science and Engineering(A)》 2016年第12期619-625,共7页
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甘蔗脱毒原种苗田间繁育过程中氮、磷、钾营养元素的吸收及累积特征 被引量:2
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作者 蒋淑停 彭李顺 +2 位作者 杨本鹏 曹峥英 杨学 《热带作物学报》 CSCD 北大核心 2024年第1期68-76,共9页
探讨甘蔗脱毒原种苗不同生长时期氮、磷、钾营养元素的累积需求状况,为甘蔗脱毒原种苗田间繁育栽培过程中养分管理提供参考。试验分别在2020、2021年进行,调查中糖1号甘蔗脱毒原种苗全生育期生长情况,测定其生物量及其在各生育阶段根、... 探讨甘蔗脱毒原种苗不同生长时期氮、磷、钾营养元素的累积需求状况,为甘蔗脱毒原种苗田间繁育栽培过程中养分管理提供参考。试验分别在2020、2021年进行,调查中糖1号甘蔗脱毒原种苗全生育期生长情况,测定其生物量及其在各生育阶段根、茎、叶中氮、磷、钾各营养元素的含量,并分析氮、磷、钾的累积量、阶段吸收量、日吸收速率。结果表明:甘蔗脱毒原种苗从种苗假植到种茎最佳收获时需6~7个月可达15茎节,在7、8月至9月下旬(茎1期至茎2期)蔗茎生长速度最快,以茎4期(10月下旬至11月下旬)干物质量累积增加最快,此阶段为生物量累积的关键阶段。在甘蔗脱毒原种苗全生育期中各元素含量及累积量从高到低依次为钾>氮>磷,在根茎叶各器官中蔗叶、蔗茎始终为氮、磷、钾含量相对较高的器官,氮、磷、钾累积量在茎伸长生长1期前主要贮存于蔗叶中,而后以蔗茎为新的主要贮存器官。甘蔗对氮、磷、钾的吸收比例在苗期和分蘖期分别为24.84%、26.18%、27.74%,在茎1~3期(7月下旬至10月下旬)分别为55.54%、58.61%、52.30%,茎4、5期(10月下旬至12月下旬)分别为19.62%、15.20%、19.96%。因此,可根据各元素的阶段吸收量进行合理施肥,进而提高甘蔗脱毒健康种苗的品质和经济效益。试验明确了甘蔗脱毒原种苗生长过程中对氮、磷、钾的需求状况,可为今后甘蔗脱毒健康种苗田间规模化繁育生产的科学合理施肥提供依据,提高脱毒原种苗田间繁育效率和养分资源利用效率。 展开更多
关键词 甘蔗 脱毒健康原种苗 氮、磷、钾养分 大量元素 养分需求状况
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适宜氮磷钾用量和配比协同促进盆栽牡丹营养和生殖生长
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作者 何晗颖 赵俊福 +4 位作者 吴欣宇 马海林 刘方春 杨婧 司东霞 《植物营养与肥料学报》 CAS CSCD 北大核心 2024年第5期1043-1052,共10页
【目的】牡丹是我国著名的木本观赏植物,施肥不平衡严重影响盆栽牡丹的生长和观赏效果。研究开花前后氮、磷、钾不同施用量和配施比例对盆栽牡丹生长的影响,确定适宜的氮、磷、钾施用量及配比,为盆栽牡丹精准施肥提供理论依据。【方法... 【目的】牡丹是我国著名的木本观赏植物,施肥不平衡严重影响盆栽牡丹的生长和观赏效果。研究开花前后氮、磷、钾不同施用量和配施比例对盆栽牡丹生长的影响,确定适宜的氮、磷、钾施用量及配比,为盆栽牡丹精准施肥提供理论依据。【方法】本研究以5年生牡丹‘紫二乔’为供试材料,采用“3414”不完全正交回归设计进行盆栽试验,结合隶属函数法评价牡丹的生长状况,利用肥料效应模型拟合牡丹植株的综合隶属函数值与施肥量之间的数学关系,得出牡丹最佳生长的氮、磷、钾肥推荐施肥量。【结果】牡丹开花前后施用氮磷钾肥显著影响植株株高、茎粗、冠幅、花径和单株花数(P<0.05),适宜氮磷钾用量和配比促进盆栽牡丹营养和生殖生长的协同提高。氮、磷、钾三因素配合处理的牡丹综合隶属函数值均大于缺素处理,缺素处理又大于无肥处理,N_(2)P_(2)K_(2)处理的综合隶属函数值(0.73)是N_(0)P_(0)K_(0)的3.17倍。氮磷钾对牡丹综合生长的影响表现为氮>磷>钾。氮、磷、钾肥对牡丹营养和生殖生长存在明显交互作用,任一肥料水平的过量或不足均会抑制牡丹植株生长,降低观赏效果。采用一元二次、二元二次、三元二次肥料效应函数方程拟合牡丹的综合隶属函数值和施肥量,二者相关性均达显著水平,综合各肥料效应函数方程的推荐用量及相应的综合隶属函数值,得出牡丹开花前后氮(N)、磷(P_(2)O_(5))、钾(K_(2)O)的最优推荐施肥量分别为4.21、2.07、2.52 g/株,适宜的氮、磷、钾施肥比例为1∶0.49∶0.60。【结论】开花前后施用适量的氮、磷、钾肥可提高牡丹的农艺性状,促进牡丹的营养和生殖生长协同提高。氮、磷、钾的最优推荐施肥量为4.21、2.07、2.52 g/株,适宜的氮、磷、钾施肥比例为1∶0.49∶0.60。 展开更多
关键词 盆栽牡丹 氮磷钾肥料 营养生长 生殖生长 最优施肥量 养分比例
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配比施肥对槟榔幼苗肥料利用率及养分协同效应的影响
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作者 降佳君 温欣宇 +4 位作者 辛晓栋 王玲 杨国斌 王朝弼 杨福孙 《热带作物学报》 CSCD 北大核心 2024年第2期315-322,共8页
为了明确N、P、K肥对槟榔幼苗生长及营养吸收与利用的影响,从而确定合理的槟榔幼苗施肥技术。以槟榔幼苗为对象,采用“3414”肥料配比田间盆栽试验,测定不同施肥处理对槟榔幼苗营养吸收与分布及肥料利用率的影响。结果表明:(1)施肥提高... 为了明确N、P、K肥对槟榔幼苗生长及营养吸收与利用的影响,从而确定合理的槟榔幼苗施肥技术。以槟榔幼苗为对象,采用“3414”肥料配比田间盆栽试验,测定不同施肥处理对槟榔幼苗营养吸收与分布及肥料利用率的影响。结果表明:(1)施肥提高了槟榔幼苗的生物量和肥料利用率;在氮磷钾平衡施肥时,氮肥和磷肥相对利用率达到最大;在不施磷肥,氮钾平衡施肥时,钾肥相对利用率达到最大;(2)槟榔幼苗地上部氮养分积累量是影响其生物量的主要因子,地下部磷养分积累量是影响其生物量的主要因子;(3)相关性分析与通径分析表明,氮与磷可协同促进槟榔幼苗生物量的增长,但会受到施钾量及钾肥相对利用率的制衡,3种元素协同促进植株生物量增长。因此氮肥和磷肥的相对利用率是槟榔幼苗施肥的关键指标。综上,氮磷钾配比施肥有利于槟榔幼苗的营养吸收和利用,以N∶P∶K=2∶2∶2(T6)配比施用效果较好。 展开更多
关键词 槟榔 氮磷钾施肥 肥料利用率 生理特性
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不同施肥处理对金瑞油桃产量和品质的影响
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作者 滑小赞 程滨 +3 位作者 赵瑞芬 侯家富 冯悦晨 王森 《山西农业科学》 2024年第1期107-114,共8页
为解决山西油桃园施肥不合理的现象,筛选出适合当地油桃生产的施肥配比和施肥量,以4年生金瑞油桃为试验材料,磷肥固定,氮肥和钾肥各设置4个梯度,以不施肥为对照,研究不同施肥处理对运城地区金瑞油桃产量和品质的影响。结果表明,适量增... 为解决山西油桃园施肥不合理的现象,筛选出适合当地油桃生产的施肥配比和施肥量,以4年生金瑞油桃为试验材料,磷肥固定,氮肥和钾肥各设置4个梯度,以不施肥为对照,研究不同施肥处理对运城地区金瑞油桃产量和品质的影响。结果表明,适量增施氮肥和钾肥均可显著增加油桃的横纵径和单果质量,提高油桃可溶性固形物、可溶性总糖和维生素C含量,降低总酸度,提高果实糖酸比,改善果实品质和口感;但施氮量超过240 kg/hm^(2)时,过量的氮肥会降低油桃可溶性固形物、维生素C和可溶性糖含量,不利于油桃品质和产量的提升。与不施肥对照相比,处理N_(2)PK_(2)(N 240 kg/hm^(2)、P_(2)O_(5)120 kg/hm^(2)和K_(2)O 240 kg/hm^(2))和处理N_(2)PK_(3)(N 240 kg/hm^(2)、P_(2)O_(5)120 kg/hm^(2)、K_(2)O 360 kg/hm^(2))增产率分别为28.77%和31.34%,增产值分别为25 440元/hm^(2)和27 720元/hm^(2),经济效益显著高于其他处理。通过构建施肥模型,试验地金瑞油桃的钾肥最佳施用量为398 kg/hm^(2)。综上,不同施肥配比和施肥量对油桃内在品质和产量有较大影响,试验地油桃适宜的氮、磷、钾施用比例为1.0∶0.5∶1.0~1.5,推荐施肥量分别为N 240 kg/hm^(2)、P_(2)O_(5)120 kg/hm^(2)、K_(2)O 240~360 kg/hm^(2)。 展开更多
关键词 金瑞油桃 氮磷钾配比 施肥量 产量 品质
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10μm 1280×1024 HgCdTe中波红外焦平面阵列探测性能提升
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作者 谭必松 毛剑宏 +9 位作者 陈殊璇 李伟伟 陈世锐 陈天晴 杜宇 彭成盼 熊雄 周永强 余波 王舒 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2024年第1期36-43,共8页
对像元尺寸为10μm的1280×1024碲镉汞(HgCdTe)中波红外焦平面阵列的制备技术和性能进行了研究。通过B+注入制备小尺寸n-on-p平面结;采用高平整度HgCdTe外延材料和高精度的倒焊互连技术,实现高的电学连通率;采用多段温度填胶固化和... 对像元尺寸为10μm的1280×1024碲镉汞(HgCdTe)中波红外焦平面阵列的制备技术和性能进行了研究。通过B+注入制备小尺寸n-on-p平面结;采用高平整度HgCdTe外延材料和高精度的倒焊互连技术,实现高的电学连通率;采用多段温度填胶固化和边缘刻蚀工艺减轻HgCdTe器件和读出集成电路(ROICs)之间的热失配,从而降低焦平面器件失效率。在85 K焦平面工作温度下,研制探测器的光谱响应范围为3.67μm至4.88μm,有效像元率高达99.95%,并且探测器组件像元的平均噪声等效温差(NETD)和暗电流密度的平均值分别小于16 mK和2.1×10^(-8)A/cm^(2)。与像元尺寸为15μm的探测器相比,10μm的1280×1024中波红外探测器可获取更加精细的图像,具有更远的识别距离。目前,该技术已成功转移到浙江珏芯微电子有限公司(ZJM)的HgCdTe红外探测器产线。 展开更多
关键词 红外探测器 碲镉汞 1 K×1 K红外焦平面阵列 n-on-p
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缓释肥对白枪杆幼苗生物量和养分积累的影响
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作者 郑绍傑 董琼 +2 位作者 叶澜 赵启泽 段华超 《森林与环境学报》 CSCD 北大核心 2024年第2期164-174,共11页
为探究4种缓释肥用量对白枪杆(Fraxinus malacophylla)幼苗氮磷钾(N、P、K)化学计量比与生物量的影响,筛选适宜苗木生长最优施肥量。以1年生白枪杆幼苗为研究对象,设置4种施肥量(0、1、2、4 kg·m^(-3)),不施肥(CK)为对照,对各器官... 为探究4种缓释肥用量对白枪杆(Fraxinus malacophylla)幼苗氮磷钾(N、P、K)化学计量比与生物量的影响,筛选适宜苗木生长最优施肥量。以1年生白枪杆幼苗为研究对象,设置4种施肥量(0、1、2、4 kg·m^(-3)),不施肥(CK)为对照,对各器官生物量、生长量及N、P、K含量进行测定,并计算N、P、K积累量;对生物量及N、P、K进行曲线拟合,分析各器官N、P、K积累量及化学计量比与生物量之间的关系。结果表明:白枪杆幼苗养分积累及生物量均在缓释肥用量为1 kg·m^(-3)下效果最佳,且显著高于对照组(P<0.05)。各器官生物量及N、P、K积累量均表现为叶>根>茎,各器官及单株养分积累量均表现为N>K>P。各器官及单株N、P、K积累量与白枪杆幼苗生物量呈极显著正相关关系(P<0.01),N∶P、K∶P与生物量呈负相关,而N∶K与生物量呈显著正相关(P<0.05)。白枪杆幼苗各器官N∶P值均小于14,植物生长受N元素限制,N∶K<2.10、K∶P>3.40,植物生长不受K影响。综上所述:缓释肥用量为1 kg·m^(-3)时,有利于白枪杆幼苗的生长及各器官养分含量的积累。 展开更多
关键词 缓释肥 养分积累 生物量 白枪杆
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甘肃中部干旱地区油用亚麻氮磷钾土壤养分丰缺指标研究
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作者 李云祥 冯玉磊 +5 位作者 常逢虎 卢军帅 胡福平 王兴富 刘谦 白斌 《中国油料作物学报》 CAS CSCD 北大核心 2024年第1期135-142,共8页
通过连续5年在甘肃中部干旱地区开展油用亚麻氮磷钾土壤养分丰缺指标田间试验研究得出:当地油用亚麻相对产量<50%(极低)、[50%~60%)(低)、[60%~70%)(较低)、[70%~80%)(中)、[80%~90%)(较高)、≥90%(高)6个肥力等级下相对应的土壤氮... 通过连续5年在甘肃中部干旱地区开展油用亚麻氮磷钾土壤养分丰缺指标田间试验研究得出:当地油用亚麻相对产量<50%(极低)、[50%~60%)(低)、[60%~70%)(较低)、[70%~80%)(中)、[80%~90%)(较高)、≥90%(高)6个肥力等级下相对应的土壤氮、磷、钾养分丰缺指标为全氮<0.38、[0.38~0.53)、[0.53~0.75)、[0.75~1.05)、[1.05~1.48)、≥1.48 g·kg^(-1);有效磷(P)<4.6、[4.6~7.8)、[7.8~13.1)、[13.1~22.1)、[22.1~37.3)、≥37.3 mg·kg^(-1);速效钾(K)<91.0、[91.0~117.3)、[117.3~151.1)、[151.1~194.7)、[194.7~250.9)、≥250.9 mg·kg^(-1);并提出了各肥力等级对应的推荐施N量分别为>130、(115~130]、(105~115]、(95~105]、(75~95]、≤75 kg·hm^(-2);施P2O5量分别为>110、(95~110]、(80~95]、(65~80]、(50~65]、≤50 kg·hm^(-2);施K_(2)O量分别为>70、(60~70]、(50~60]、(40~50]、(35~40]、≤35 kg·hm^(-2)。长期土壤养分监测表明,自1983年至今,当地油用亚麻产区土壤碱解氮、有效磷含量均呈上升趋势,全氮含量略有下降,速效钾含量则下降明显。从试验所得丰缺指标亦看出,目前当地土壤氮、磷素养分含量仍处于较低水平,而钾素养分含量虽仍处于较高水平,但与以往相比却呈明显下降趋势,表明当地油用亚麻生产中既要重施氮肥,增施磷肥,还要适当补施钾肥。 展开更多
关键词 干旱地区 亚麻 土壤氮磷钾 丰缺指标 施肥指标
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半夏测土配方施肥产量效应和氮磷钾吸收特性分析
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作者 陈晓芳 张翔宇 +3 位作者 柳敏 王彩云 周茂嫦 李恒谦 《中国野生植物资源》 CSCD 2024年第2期1-7,19,共8页
目的:探索肥效对贵州半夏产量及养分吸收特性的影响。方法:采用“3414”测土配方施肥考察半夏产量及不同时期块茎对氮磷钾吸收特性,SPSS 22.0进行肥效方程拟合及不同时期块茎氮磷钾吸收的显著性分析。结果:氮、磷、钾肥施用量的变化对... 目的:探索肥效对贵州半夏产量及养分吸收特性的影响。方法:采用“3414”测土配方施肥考察半夏产量及不同时期块茎对氮磷钾吸收特性,SPSS 22.0进行肥效方程拟合及不同时期块茎氮磷钾吸收的显著性分析。结果:氮、磷、钾肥施用量的变化对半夏产量具有显著相关性,通过对氮、磷、钾肥施用量与半夏产量的关系拟合得到单因素肥效方程、三因素肥效模型以及不同时期块茎吸收氮磷钾与产量的相关性模型,该区域半夏最佳施肥策略为氮肥74.19 kg/hm^(2)、磷肥87.28 kg/hm^(2)、钾肥25.48 kg/hm^(2);不同时期块茎对氮的吸收受磷肥施用的影响,当磷肥施用处于较高水平时,块茎对氮的吸收也处于较高水平;块茎对磷的吸收受钾肥施用的影响,当钾肥施用处于较低水平时,对磷的吸收处于较高水平;块茎对钾的吸收则受氮、磷施用的共同影响,高钾的施用有利于块茎对钾的吸收。结论:半夏不同生长期应采取不同的施肥策略以达到更高的产量,本研究对贵州半夏高产栽培有一定指导意义。 展开更多
关键词 配方施肥 半夏 氮磷钾 产量
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凉山州白术氮磷钾配比水溶施肥试验初探
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作者 冯奎 阿则晓龙 +2 位作者 汪扬媚 刘言 董红平 《四川农业与农机》 2024年第2期50-51,54,共3页
为摸清凉山州白术种植施用N、P、K有效方式,促进提高产量,团队通过在凉山州二半山区土壤肥力高、中、低三个地块上进行白术N、P、K施用试验,结果显示,在土壤肥力高的区域,配比水溶施肥对产量影响大,但与配比不水溶施肥对产量影响差别不... 为摸清凉山州白术种植施用N、P、K有效方式,促进提高产量,团队通过在凉山州二半山区土壤肥力高、中、低三个地块上进行白术N、P、K施用试验,结果显示,在土壤肥力高的区域,配比水溶施肥对产量影响大,但与配比不水溶施肥对产量影响差别不大,与等比例施肥效果更显著;土壤肥力中等的区域,配比水溶施肥与配比施肥的产量相差不大,配比水溶施肥比等比例水溶施肥的产量较高;土壤肥力低的区域,配比水溶施肥与直接配比施肥的产量近似,但与等比例施肥的产量高。因此,按照白术所需N、P、K的量,将不同的肥料所含元素比例进行精准测算后进行配比水溶施肥,可以提高白术亩产量。 展开更多
关键词 凉山 二半山区 白术种植 N、P、K施肥
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不同氮磷钾镁配比对砀山酥梨生长和养分吸收的影响
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作者 王岩 《中国高新科技》 2024年第2期153-154,160,共3页
文章旨在探讨不同氮磷钾镁配比对砀山县酥梨的生长及营养物质吸收的影响。试验结果表明:在氮磷钾镁含量相同的条件下,不同配比对酥梨株高、枝数、叶面积、花芽形成率、果实发育情况及果实品质都有显著影响;不同配比对植株根系长度、干... 文章旨在探讨不同氮磷钾镁配比对砀山县酥梨的生长及营养物质吸收的影响。试验结果表明:在氮磷钾镁含量相同的条件下,不同配比对酥梨株高、枝数、叶面积、花芽形成率、果实发育情况及果实品质都有显著影响;不同配比对植株根系长度、干重、总糖含量、酸度、果汁含水量、果粒质量有明显差异;不同配比对土壤中有机质、矿质元素含量也有明显变化。其中,氮磷钾镁为1:2:1的比例下,酥梨株高最高,产量最大;氮磷钾镁为2:3:1的比例下,酥梨株高最低,但产量也较大;氮磷钾镁比例为1:4:0的比例下,酥梨株高最小,但果实品质最好。因此,建议在砀山县栽培酥梨时,应根据当地气候条件、肥料供应状况等综合因素来合理选择氮磷钾镁配比,以提高酥梨的经济效益。 展开更多
关键词 氮磷钾镁 配比优化 砀山酥梨
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A Preliminary Study on Dynamics and Models of N,P,K Absorption for High-Yield Cotton 被引量:6
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作者 WANGKe-ru LIShao-kun +3 位作者 CAOLian-pu SONGGuang-jie CHENGang CAOSuan-zhu 《Agricultural Sciences in China》 CAS CSCD 2003年第7期752-759,共8页
The field experiments were carried out to investigate the dynamics and models of N, P and K absorption for the cotton plants with a lint of 3 000 kg ha-1 in Xinjiang. The main results were as follows: The contents of ... The field experiments were carried out to investigate the dynamics and models of N, P and K absorption for the cotton plants with a lint of 3 000 kg ha-1 in Xinjiang. The main results were as follows: The contents of N, P2O5, K2O in cotton leaves, stems, squares and bolls decreased obviously with the time over the whole growth duration and the falling extent was greater in high-yield cotton than in CK. Contents of N in leaves, squares and bolls, in particular in the leaves of fruit-bearing shoot was higher in high-yield cotton than in CK. Contents of P2O5 in squares and bolls and that of K2O in stems were higher in high-yield cotton than in CK during the whole growing period. The accumulations of N, P2O5 and K2O in the cotton plants could be described with a logistic curve equation. There was the fastest nutrient uptake at about 90 d for N, 92 d for P2O5 and 85 d for K2O after emergence, respectively. Total nutrient accumulation of N, P2O5 and K2O was 385.8, 244. 7 and 340.3 kg ha-1, respectively. Approximately 12. 5 kg N, 8. 0 kg P2O5 and 11.1 kg K2O were needed for producing 100 kg lint with the leaves and stems under the super high yield condition of 3 000 kg ha-1 in Xinjiang. 展开更多
关键词 XINJIANG Cultivation of high yield COTTON N P K Absorption dynamics Model
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N,P,and K characteristics of different age groups of temperate coniferous tree species in northwestern China 被引量:2
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作者 Simin Liu Hao Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第2期465-472,共8页
This study chose dominant tree species including Picea crassifolia,Pinus armandii and Pinus tabuliformis which are distributed in Qilian Mountains,Xiaolongshan Mountains,and Bailongjiang River.According to the differe... This study chose dominant tree species including Picea crassifolia,Pinus armandii and Pinus tabuliformis which are distributed in Qilian Mountains,Xiaolongshan Mountains,and Bailongjiang River.According to the different tree species,ages and components,we sampled leaves,branches,stems,and roots,and measured the contents of Nitrogen,Phosphorus,Potassium,along with soil fertility.The changes of N,P,and K contents in the different tree species were studied,and the relationship between nutrient content and environmental factors was analyzed.The results indicated that the content of P in all three species was the lowest(0.039–0.28 g kg),while N content was the highest(0.095–1.72 g kg).As the terminal organ of nutrient transport,the nutrient content of leaves was the highest.P.armandii(0.45 g kg) had a higher nutrient concentration than P.tabulaeformis(0.19 g kg) and P.crassifolia(0.29 g kg).The nutrient content of each species was highest in a young forest,but lowest in a mature forest.The nutrient content of all three tree species was significantly affected by soil nutrient content,and negatively correlated with available soil nutrients. 展开更多
关键词 Different ages Northwestern China N P K Tree species
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Effects of Amino Acids Replacing Nitrate on Growth,Nitrate Accumulation,and Macroelement Concentrations in Pak-choi (Brassica chinensis L.) 被引量:12
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作者 WANG Hua-Jing WU Liang-Huan +3 位作者 WANG Min-Yan ZHU Yuan-Hong TAO Qin-Nan ZHANG Fu-Suo 《Pedosphere》 SCIE CAS CSCD 2007年第5期595-600,共6页
一个水耕法的实验被执行决定在小白菜(Brassica chinensis L.) 在氮(N) ,磷(P) ,和钾(K) 的生长,硝酸盐累积,和集中上用 20 单个氨基酸在营养液代替 20% nitrate-N 的影响射击。20% nitrate-N 什么时候与完整的硝酸盐处理,新鲜的... 一个水耕法的实验被执行决定在小白菜(Brassica chinensis L.) 在氮(N) ,磷(P) ,和钾(K) 的生长,硝酸盐累积,和集中上用 20 单个氨基酸在营养液代替 20% nitrate-N 的影响射击。20% nitrate-N 什么时候与完整的硝酸盐处理,新鲜的小白菜射击和干燥重量相比被精氨酸( Arg )代替,但是20% nitrate-N 什么时候被丙氨酸(翼)代替,显著地增加了( P ≤ 0.05 ),缬氨酸(瓦尔),白氨酸(列伊),异白氨酸( Ile ),脯氨酸(专业版),本氨基丙酸( Phe ),蛋氨酸(相遇),天门冬酸(毒蛇), glutamic ( Glu ),离氨酸( Lys ),甘氨酸( Gly ),丝氨酸(重量的单位),苏氨酸( Thr ),半胱氨酸( Cys ),和酷氨酸( Tyr ),新鲜的射击和干燥重量显著地减少了( P ≤ 0.05 )。在用天门冬素(Asn ) 和夫酸安(Gln ) 代替 20% nitrate-N 以后,新鲜的射击和干燥重量是未受影响的。比作完整的硝酸盐处理,氨基酸代替处理除了 Cys, Gly,组氨酸(他的) ,并且 Arg,显著地减少了(P ≤ 0.05 ) 在植物射击的硝酸盐集中。显著地除了 Cys,列伊,专业版,和在另外的氨基酸处理的植物组织的遇见的、全部的 N 集中增加了(P ≤ 0.05 ) 。氨基酸也影响了全部的 P 和 K 集中,但是效果不同取决于单个氨基酸。改进小白菜射击质量, Gln 和 Asn 由于他们小白菜生长上的不足道的效果,他们在硝酸盐集中的重要减小,和他们宏元素的增加在植物满足,可以被用来部分代替 nitrate-N。 展开更多
关键词 芸苔 氨基酸 生长发育 硝酸盐积累
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Direct rapid determination of traces of sulfide in environment samples 被引量:1
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作者 郭方遒 黄兰芳 梁逸曾 《Journal of Central South University of Technology》 2002年第4期250-254,共5页
An improved ethylene blue method for determination of sulfide is developed. It has been adapted to a direct determination of sulfide by both common spectrophotometric method and total differential spectrophotometric m... An improved ethylene blue method for determination of sulfide is developed. It has been adapted to a direct determination of sulfide by both common spectrophotometric method and total differential spectrophotometric method. In common spectrophotometric method, the calibration curve is A=1.69ρ + 0.006 and the correlation coefficient is 0.9994.The apparent molar absorptivity is 5.42×10 4 L·mol -1 ·cm -1 and calibration curve is liner when ρ is in the range of 0 0.9 mg·L -1 . In total differential spectrophotometric method, the calibration curve is A=9.25ρ +0.004 and the correlation coefficient is 0.9996. The apparent molar absorptivity is 2.96×10 5 L·mol -1 ·cm -1 and calibration curve is liner when ρ is in the range of 0 0.10 mg·L -1 . The sensitivity of this method is increased significantly compared with the former ethylene blue method. The speed of reaction is also faster than the former one. The limit of detection is found to be 1.0 ng·mL -1 by both common spectrophotometric method and total differential spectrophotometric method. Ten replicate analyses of a sample solution containing 100 ng·mL -1 sulfide give a relative standard deviation of 1.8%. The effects of various cations and anions on the determination of sulfide are studied and procedures for removal of interference is described. The method is used for the determination of sulfide in environment samples with satisfactory results. 展开更多
关键词 total differential SPECTROPHOTOMETRIC method p-amino-N N-diethylaniline K2Cr2O7 SULFIDE ENVIRONMENT SAMPLES
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Short-term influence of anaerobically-digested and conventional swine manure, and N fertilizer on organic C and N, and available nutrients in two contrasting soils
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作者 Sukhdev S. Malhi R. L. Lemke +1 位作者 M. Stumborg F. Selles 《Agricultural Sciences》 2012年第5期678-696,共19页
A three-year (2006-2008) field experiment was conducted at Swift Current and Star City in Saskatchewan to determine the short-term in-fluence of land-applied anaerobically digested swine manure (ADSM), conventionally ... A three-year (2006-2008) field experiment was conducted at Swift Current and Star City in Saskatchewan to determine the short-term in-fluence of land-applied anaerobically digested swine manure (ADSM), conventionally treated swine manure (CTSM) and N fertilizer on total organic C (TOC), total organic N (TON), light fraction organic C (LFOC), light fraction organic N (LFON) and pH in the 0 - 7.5 and 7.5 - 15 cm soil layers, and ammonium-N, nitrate-N, extractable P, exchangeable K and sulphate-S in the 0 - 15, 15 - 30, 30 - 60, 60 - 90 and 90 - 120 cm soil layers. Treatments included spring and autumn applications of CTSM and ADSM at a 1x rate (10,000 and 7150 L·ha-1, respectively) applied each year, a 3x rate (30,000 and 21,450 L·ha-1, respectively) applied once at the beginning of the experiment, plus a treatment receiving commercial fertilizer (UAN at 60 kg·N·ha-1·yr-1) and a zero-N control. There was no effect of swine manure rate, type and application time on soil pH. Mass of TOC and TON in the 15 cm soil layer increased significantly with swine manure application compared to the control, mainly at the Swift Current site, with greater increases from 3x rate than 1x rate (by 2.21 Mg·C·ha-1 and 0.167 Mg·N·ha-1). Compared to the control, mass of LFOC and LFON in the 15 cm soil layer increased with swine manure application at sites, with greater increases from 3x rate than 1x rate (by 287 kg·C·ha-1 and 26 kg·N·ha-1 at Star City, and by 194 kg·C·ha-1 and 19·kg·N ha-1 at Swift Current). Mass of TOC and TON in soil layer was tended to be greater with ADSM than CTSM, but mass of LFOC and LFON in soil was greater with CTSM than ADSM. Mass of TOC, TON, LFOC and LFON in soil also increased with annual N fertilizer application compared to the control (by 3.2 Mg·C·ha-1 for TOC, 0.195 Mg·N·ha-1 for TON, 708 kg·C·ha-1 for LFOC and 45 kg·N·ha-1 for LFON). In conclusion, our findings suggest that the quantity and quality of organic C and N in soil can be affected by swine manure rate and type, and N fertilization even after three years, most likely by influencing inputs of C and N through crop residue, and improve soil quality. 展开更多
关键词 ANAEROBIC DIGESTION Available N P K and S Organic C and N Soil SWINE MANURE
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