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Preliminary discussion on the ignition mechanism of exploding foil initiators igniting boron potassium nitrate 被引量:1
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作者 Haotian Jian Guoqiang Zheng +4 位作者 Lejian Chen Zheng Ning Guofu Yin Peng Zhu Ruiqi Shen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期222-231,共10页
Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ig... Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting pyrotechnics.An oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma temperature.The results of the electric characteristics and the impact pressure were inconsistent with ignition results.The only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating explosives.Furthermore,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this paper.The HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric explosion.The longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success. 展开更多
关键词 Exploding foil initiator PDV Plasma spectrum Ignition mechanism Boron potassium nitrate
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Physiological and molecular mechanisms of cytokinin involvement in nitrate-mediated adventitious root formation in apples
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作者 Muhammad Mobeen Tahir Li Fan +9 位作者 Zhimin Liu Humayun Raza Usman Aziz Asad Shehzaib Shaohuan Li Yinnan He Yicen Lu Xiaoying Ren Dong Zhang Jiangping Mao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第12期4046-4057,共12页
Potassium nitrate(KNO_(3))promotes adventitious root(AR)formation in apple stem cuttings.However,evidence for the possible involvement of cytokinin(CK)in KNO_(3)-mediated AR formation in apples is still lacking.In thi... Potassium nitrate(KNO_(3))promotes adventitious root(AR)formation in apple stem cuttings.However,evidence for the possible involvement of cytokinin(CK)in KNO_(3)-mediated AR formation in apples is still lacking.In this study,we cultured GL-3 apple microshoots in different treatment combinations.While the T1(KNO_(3)9.4 mmol L^(-1)+6-benzyl adenine(6-BA)2.22μmol L^(-1))and T3(6-BA 2.22μmol L^(-1))treatments completely inhibited AR formation,the control,T2(KNO_(3)9.4 mmol L^(-1)),and T4(KNO_(3)9.4 mmol L^(-1)+lovastatin(Lov)1.24μmol L^(-1))treatments developed ARs.However,T4-treated microshoots developed fewer and shorter ARs,indicating that optimum CK synthesis is needed for normal AR growth.This also suggests that these fewer and shorter ARs developed because of the presence of KNO_(3) in the same medium.The anatomy of the stem basal part indicated that the inhibition of CK biosynthesis delayed AR primordia formation.The endogenous levels of indole-3-acetic acid(IAA)and zeatin riboside(ZR)were higher in T2-treated microshoots,while the abscisic acid(ABA),gibberellic acid 3(GA_(3)),and brassinosteroid(BR)levels were higher in T4-treated microshoots.The expression levels of MdNRT1.1and MdNRT2.1 were higher in T2-treated microshoots at 3 and 8 days,while MdRR2 and MdCKX5 were higher at 8 and 16 days,respectively.Furthermore,higher IAA levels increased MdWOX11 expression,which in turn increased MdLBD16 and MdLBD29 expression in response to T2.The combined expression of these genes stimulated adventitious rooting by upregulating cell cycle-related genes(MdCYCD1;1 and MdCYCD3;1)in response to T2 treatment.This study shows that specific genes and hormonal pathways contribute to KNO_(3)-CK-mediated adventitious rooting in apples. 展开更多
关键词 adventitious root(AR) cytokinin(CK) potassium nitrate(KNO_(3)) CROSSTALK HORMONES gene expression
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Effects of a new nitrification inhibitor 3,4-dimethylpyrazole phosphate(DMPP) on nitrate and potassium leaching in two soils 被引量:12
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作者 WU Shao-fu WU Liang-huan +3 位作者 SHI Qi-wei WANG Zhong-qiang CHEN Xian-you LI Yong-shan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第7期841-847,共7页
In this study, soil column was used to study the new nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) on nitrate (NO3^-- N) and potassium (K) leaching in the sandy loam soil and clay loam soil. The ... In this study, soil column was used to study the new nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) on nitrate (NO3^-- N) and potassium (K) leaching in the sandy loam soil and clay loam soil. The results showed that DMPP with ammonium sulphate nitrate (ASN) ((NH4)2SO4 and NHaNO3) or urea could reduce NO3^--N leaching significantly, whereas ammonium (NH4^+-N) leaching increased slightly. In case of total N (NO3^--N+NH4^+-N), losses by leaching during the experimental period (40 d) were 37.93 mg (urea), 31.61 mg (urea+DMPP), 108.10 mg (ASN), 60.70 mg (ASN+DMPP) in the sandy loam soil, and 30.54 mg (urea), 21.05 mg (urea+DMPP), 37.86 mg (ASN), 31.09 mg (ASN+DMPP) in the clay loam soil, respectively. DMPP-amended soil led to the maintenance of relatively high levels of NH4^+ -N and low levels of NO3^--N in soil, and nitrification was slower. DMPP supplementation also resulted in less potassium leached, but the difference was not significant except the treatment of ASN and ASN+DMPP in the sandy loam soil. Above results indicate that DMPP is a good nitrification inhibitor, the efficiency of DMPP seems better in the sandy loam soil than in the clay loam soil and lasts longer. 展开更多
关键词 3 4-dimethylpyrazole phosphate (DMPP) nitrate potassium LEACHING sandy loam soil clay loam soil
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The Effect of Different Levels of Salinity and Potassium Nitrate on the Germination of Cocks Comb (<i>Celosia cristata</i>)
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作者 Zahra Golshadi Ghaleh-Shahi Hossein Zarei +3 位作者 Mehrdad Babarabie Atoosa Danyaei Madeh Ahmadi Sima Badeli 《Open Journal of Ecology》 2017年第4期289-299,共11页
Cocks Comb (Celosia cristata) is a hot-season annual species which is grown from seeds. A study was carried out in the horticulture laboratory of Gorgan University of Agriculture Science and Natural Resources of Febru... Cocks Comb (Celosia cristata) is a hot-season annual species which is grown from seeds. A study was carried out in the horticulture laboratory of Gorgan University of Agriculture Science and Natural Resources of February 2013 to evaluate the impact of salinity and potassium nitrate on the germination of cockscomb with five salinity levels (0, &minus;2, &minus;4, &minus;6, and &minus;8 bars) and three potassium nitrate levels (0%, 0.2%, and 0.4%) at 25&deg;C on the basis of a Randomized Complete Block Design. Analysis of variance showed significant differences among salinity levels in germination percentage, radicle length, plumule length, and seed vigor at the 1% probability level. Mean comparison for germination percentage revealed that higher salinity reduced seed germination percentage so that it was decreased from 80% in no salinity to 15% in &minus;8 dS&sdot;m&minus;1. The highest percentage of germination was related to zero percent salt and potassium nitrate 0.2%. Also, the highest radicle length of 2.48 cm was related to no salinity and the lowest one (0.61 cm) to &minus;6 dS salinity. The highest radicle length and seed vigor were also observed in no salinity. Potassium nitrate by itself had no impact on the measured traits. Among interactions between salinity and potassium nitrate, the highest germination percentage was observed under 0 salinity × 0.2% potassium nitrate. 展开更多
关键词 Amarantaceae COCKS COMB GERMINATION Percentage potassium nitrate SALINITY
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Crystallization Kinetics of Batch Spontaneous Nucleation of Potassium Nitrate
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作者 伍川 黄培 +3 位作者 黄德春 杨红群 徐南平 时钧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第5期589-595,共7页
The batch cooling crystallization initiated from spontaneous nucleation for aqueous solution of potassium nitrate was studied. The concentration and transmittance data were acquired on line throughout the operation.Ba... The batch cooling crystallization initiated from spontaneous nucleation for aqueous solution of potassium nitrate was studied. The concentration and transmittance data were acquired on line throughout the operation.Based on solute mass transfer in both liquid and solid phases, a kinetic model was deduced by assuming that the late period of primary nucleation resembles the initial period of the secondary nucleation. Nucleation and crystal growth stages were identified. Kinetic parameters were estimated piecewise from online experimental data and compared with those in literature. The estimated kinetic parameters for stages without apparent primary nucleation agreed well with those in literature. Further, a simulated concentration curve was also drawn from the estimated kinetic parameters and it matched well with that in experiment. 展开更多
关键词 potassium nitrate batch spontaneous crystallization mathematical modeling parameter estimation NUCLEATION crystal growth
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Packaging category and its influencing factors of potassium nitrate
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作者 WEI Shao-jie TAN Ying-xin FANG Fan 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第4期379-382,共4页
To understand the combustion characteristics of potassium nitrate and evaluate the magnitude of combustion risk, ox-idation solid test apparatus is used and the updated experimental criterion of the United Nations is... To understand the combustion characteristics of potassium nitrate and evaluate the magnitude of combustion risk, ox-idation solid test apparatus is used and the updated experimental criterion of the United Nations is adopted to measure the pack-aging category of potassium nitrate. The new criterion puts calcium peroxide and microcrystalline cellulose as references and burning rate as evaluation index. Effects of mixing ratio and insert medium on burning rate are reached. Test results show that pure potassium nitrate doesn't burn under normal temperature and pressure, however, its oxidation is very strong and the packaging category should choose the class I. As the mass fraction of potassium nitrate reduces, the burning rate first increases and then decreases. When the ratio is 2 : 1,the combustion rate reaches the maximum, and the effect of combustion is the best. When 1 : 3, the combustion rate is the minimum. The mixture combustion can be suppressed by silicon dioxide and hy-drogen phosphate, which is not fired when silica concentration is 40% or ammonium hydrogen potassium phosphate is 55%, their effects are very obvious. 展开更多
关键词 potassium nitrate packaging category mixture ratio inert medium combustion rate
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Kinetics and Mechanism of Spontaneous Crystallization of Potassium Nitrate from Its Supersaturated Aqueous Potassium Nitrate from Its Supersaturated Aqueous Solutions
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作者 Oleg D. Linnikov Irina V. Rodina +1 位作者 Igor G. Grigorov Evgeniy V. Polyakov 《Crystal Structure Theory and Applications》 2013年第1期16-27,共12页
Kinetics of spontaneous crystallization of potassium nitrate from its supersaturated aqueous solutions has been studied simultaneously by electrical conductance and optical transmittance methods. It was found that spo... Kinetics of spontaneous crystallization of potassium nitrate from its supersaturated aqueous solutions has been studied simultaneously by electrical conductance and optical transmittance methods. It was found that spontaneous crystallization of potassium nitrate was accompanied by aggregation of crystals. Growth of salt crystals was in the kinetic mode of the growth process, and was described by the equation of the first order regarding supersaturation of solution. The mechanism of aggregation and intergrowth of crystals during bulk crystallization via formation of nucleus-bridges between crystals found earlier for several salts was confirmed. Specific surface energy of potassium nitrate was evaluated on the basis of the above mechanism of aggregation and intergrowth of crystals. The established value of the specific surface energy was reasonable and agreed satisfactorily with the available literature data. Examination of crystal deposit after completion of crystallization allowed detecting crystal agglomerates of freakish and irregular forms, which may be considered as the direct confirmation of the above mechanism of intergrowth of crystals. Kinetics of crystallization, aggregation and size distribution of salt crystals after completion of crystallization have been satisfactory described by the earlier proposed model of the crystallization process. An excellent agreement was established between the experimental data on potassium nitrate solubility in aqueous solutions found in the present work and those available in the literature. 展开更多
关键词 potassium nitrate Aggregation Crystallization SOLUBILITY Activation Energy Crystal Growth INTERGROWTH AGGLOMERATES
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Phosphorylation regulation of nitrogen,phosphorus,and potassium uptake systems in plants 被引量:1
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作者 Dongli Hao Xiaohui Li +4 位作者 Weiyi Kong Rongrong Chen Jianxiu Liu Hailin Guo Jinyan Zhou 《The Crop Journal》 SCIE CSCD 2023年第4期1034-1047,共14页
The uptake of ammonium,nitrate,phosphorus,and potassium ions by roots is mediated by specific ion transporter or channel proteins,and protein phosphorylation regulation events occurring on these proteins and their reg... The uptake of ammonium,nitrate,phosphorus,and potassium ions by roots is mediated by specific ion transporter or channel proteins,and protein phosphorylation regulation events occurring on these proteins and their regulators determine their ultimate activity.Elucidating the mechanism by which protein phosphorylation modification regulates nutrient uptake will advance plant breeding for high nutrientuse efficiency.In this review,it is concluded that the root nutrient absorption system is composed of several,but not all,members of a specific ion transporter or channel family.Under nutrient-starvation conditions,protein phosphorylation-based regulation of these proteins and associated transcription factors increases ion transporter-or channel-mediated nutrient uptake capacity via direct function activity enhancement,allowing more protein trafficking to the plasma membrane,by strengthening the interaction of transporters and channels with partner proteins,by increasing their protein stability,and by transcriptional activation.Under excessive nutrient conditions,protein phosphorylation-based regulation suppresses nutrient uptake by reversing these processes.Strengthening phosphorylation regulation items that increase nutrient absorption and weakening phosphorylation modification items that are not conducive to nutrient absorption show potential as strategies for increasing nutrient use efficiency. 展开更多
关键词 Ammonium uptake machinery nitrate uptake machinery Phosphate uptake machinery potassium uptake machinery Transcription factors Protein phosphorylation
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Synthesis and Characterization of Ultra-fine Cr_2O_3 from Hydrogen Reduction of K_2CrO_4
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作者 BAI Yulan XU Hongbin +1 位作者 ZHANG Yi LI Zuohu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2008年第2期181-183,共3页
As a part of the green process for manufacturing chromium compounds, two steps are involved in the synthesis of ultra-fine Cr2O3 powders: the first is the hydrogen reduction of K2CrO4 into intermediate trivalent (C... As a part of the green process for manufacturing chromium compounds, two steps are involved in the synthesis of ultra-fine Cr2O3 powders: the first is the hydrogen reduction of K2CrO4 into intermediate trivalent (Cr^3+) or tetravalent (Cr^4+) chromium compounds; the second is the decomposing of the intermediate into Cr2O3 by heat treating. The intermediate is well characterized by means of SEM, XRD, and XPS. The possible reaction mechanism of the process is analyzed. 展开更多
关键词 hydrogen reduction ultra-fine chromic oxide potassium chromate green process
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Effects of Calcium Nitrate Levels and Soaking Durations on Cocopeat Nutrient Content
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作者 Sheku N. Gbollie Samuel M. Mwonga Anthony M. Kibe 《Journal of Agricultural Chemistry and Environment》 2021年第3期372-388,共17页
Cocopeat, a by-product of the coconut (<em>Cocos nucifera </em>L.), is an important soilless media that contains high potassium (K), sodium (Na), and electrical conductivity (EC) depending on its source. M... Cocopeat, a by-product of the coconut (<em>Cocos nucifera </em>L.), is an important soilless media that contains high potassium (K), sodium (Na), and electrical conductivity (EC) depending on its source. Methods for extracting these elements and thus lowering EC are yet to be standardized. This study was therefore carried out to investigate two extraction methods of these elements in cocopeat. A greenhouse pot experiment was carried out at the Climate and Water Smart Agriculture Centre of Egerton University, Kenya. It was laid out in a 5 × 4 factorial completely randomized design. Five soaking durations (12, 24, 36, 48, and 72 hours) and four calcium nitrate (Ca(NO<sub>3</sub>)<sub>2</sub>) levels (0, 60, 100, and 150 g) were used. The experiment was done in two folds: the leachate and treated cocopeat examination for their chemical properties. The General Linear Model procedures were used for Analysis of Variance at (P ≤ 0.05). The results showed that the addition of Ca(NO<sub>3</sub>)<sub>2</sub> 100 g extracted significantly more K and Na in the leachate than Ca(NO<sub>3</sub>)<sub>2</sub> 0.0 g and 60 g. The EC levels in the leachate increased with the application levels of Ca(NO<sub>3</sub>)<sub>2</sub> while the pH levels were reducing. In the treated cocopeat, Ca(NO<sub>3</sub>)<sub>2</sub> 100 g and soaking duration 36 hours significantly reduced K and Na and sufficiently supplemented Ca and N. Irrespective of Ca(NO<sub>3</sub>)<sub>2</sub> and soaking durations, after the cocopeat is washed, the EC and pH values fall within their suitable ranges. There was a strong negative correlation between Ca and Na, Ca and K, and between Na and EC. Also, strong positive correlation between Ca and N and Ca and EC. Effective supplementation of Ca and N, and optimal reduction of K and Na by 78.44% and 92%, respectively can be achieved with 100 g of Ca(NO<sub>3</sub>)<sub>2</sub> 1.5 kg<sup>-1</sup> of cocopeat in 15 liters of water with a soaking duration of 36 hours. 展开更多
关键词 Calcium nitrate Cocopeat LEACHATE potassium SOAKING
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硝酸钾配施有机肥对早熟禾生长及养分吸收的影响 被引量:1
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作者 张吉立 刘振平 +2 位作者 何晓蕾 王宁 王鹏 《黑龙江八一农垦大学学报》 2024年第1期9-14,共6页
早熟禾草坪在盐碱土壤上建植3~4年后会发生明显的退化,研究园林养护中采用硝酸钾配施有机肥的方式为其提供营养,对促进植株生长和提高坪用质量具有重要意义。试验设置在城市绿化带中,设置空白对照(K1)、硝酸钾化肥对照(K2)、化肥+发酵饼... 早熟禾草坪在盐碱土壤上建植3~4年后会发生明显的退化,研究园林养护中采用硝酸钾配施有机肥的方式为其提供营养,对促进植株生长和提高坪用质量具有重要意义。试验设置在城市绿化带中,设置空白对照(K1)、硝酸钾化肥对照(K2)、化肥+发酵饼肥(K3)、化肥+腐殖酸复混肥(K4)4个处理,每个处理3次重复,研究了早熟禾生长和养分吸收变化。结果表明:K3与K1相比,在7~10月有利于提高早熟禾干物质积累量、含水量、叶绿素a、叶绿素b和类胡萝卜素含量,显著提高了植株氮、磷、钾吸收量;K3与K2相比,在8~9月显著提高了干物质积累量,7月和10月显著提高了叶绿素b和类胡萝卜素含量,8~10月提高了氮磷钾养分吸收量;K3与K4相比,在7~9月提高了干物质积累量,7~10月显著提高了叶绿素b和类胡萝卜素含量,促进了氮磷钾营养元素的吸收。综合分析认为,硝酸钾配施发酵饼肥为适宜施肥处理。 展开更多
关键词 早熟禾 硝酸钾 干物质积累 养分吸收 叶绿素
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麦饭石和硝酸钾添加对石油污染土壤的生物修复作用
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作者 杨钊 刘泽梁 +2 位作者 冯爽 张旭红 吴蔓莉 《农业环境科学学报》 CAS CSCD 北大核心 2024年第9期2014-2021,共8页
为研究麦饭石和硝酸钾对石油污染土壤的生物修复作用,本试验通过向石油污染土壤中投加麦饭石和硝酸钾,比较了两种修复剂对不同污染时长土壤中石油烃的去除作用和毒性抑制效果。结果表明:对于新污染土壤,施加硝酸钾和麦饭石修复110 d后,... 为研究麦饭石和硝酸钾对石油污染土壤的生物修复作用,本试验通过向石油污染土壤中投加麦饭石和硝酸钾,比较了两种修复剂对不同污染时长土壤中石油烃的去除作用和毒性抑制效果。结果表明:对于新污染土壤,施加硝酸钾和麦饭石修复110 d后,总石油烃(Total petroleum hydrocarbon,TPH)的去除率分别为12.03%和17.09%。其中,施加硝酸钾修复45 d时主要增强了土壤微生物的硝化潜力,修复后期(第46~110天)主要通过强化好氧反硝化作用实现对TPH的去除。对于陈旧性污染土壤,投加硝酸钾和麦饭石修复110 d后,TPH去除率分别为24.41%和22.07%,石油烃的去除主要发生在修复后期(第46~110天)。陈旧性污染土壤中添加硝酸钾提高了土壤微生物固氮和硝化潜力。麦饭石的添加对不同污染时长土壤中石油烃的去除主要通过吸附作用实现。蚯蚓急性毒性实验结果表明,麦饭石处理组蚯蚓7 d平均死亡率为35%,显著低于对照组的60%和硝酸钾处理组的100%死亡率,表明施入硝酸钾修复显著增强了土壤的生态毒性,施入麦饭石可降低石油污染土壤的生态毒性。研究表明,相比硝酸钾,麦饭石兼具石油烃去除和降低土壤生态毒性的作用,可作为一种优质修复剂处理石油污染土壤。 展开更多
关键词 石油污染土壤 生物刺激 生态毒性 麦饭石 硝酸钾
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硝酸钾配施发酵饼肥对景观草坪坪用质量的影响 被引量:1
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作者 张吉立 刘振平 《信阳农林学院学报》 2024年第1期95-100,共6页
通过研究硝酸钾配施发酵饼肥对草地早熟禾草坪坪用质量影响的规律,可以为城市园林草坪养护的科学施肥提供理论依据。试验在城市环境条件下,设置对照(CK)、硝酸钾(K_(1))、硝酸钾+发酵饼肥(K_(2))、硝酸钾+腐殖酸复混肥(K_(3))4个处理,... 通过研究硝酸钾配施发酵饼肥对草地早熟禾草坪坪用质量影响的规律,可以为城市园林草坪养护的科学施肥提供理论依据。试验在城市环境条件下,设置对照(CK)、硝酸钾(K_(1))、硝酸钾+发酵饼肥(K_(2))、硝酸钾+腐殖酸复混肥(K_(3))4个处理,小区试验设计,3次重复。结果表明:6月,K_(1)处理分蘖密度、株高、叶长、叶绿素含量均显著高于CK、K_(2)和K_(3)处理;7-10月,K_(2)分蘖密度显著高于CK、K_(1)和K_(3),6-8月K_(1)与K_(3)均显著高于CK;6-10月,K_(2)处理盖度显著高于CK,6-7月和9-10月K_(2)显著高于K_(1);7-10月K_(2)株高和叶长均显著高于CK,8月和10月K_(2)显著高于K_(1);7月、8月和10月,K_(2)处理叶宽显著高于对照;7-10月,K_(2)处理叶绿素含量和植株鲜重均显著高于CK,K_(2)显著高于K_(3)。综合分析认为,在现有施肥量基础上硝酸钾与发酵饼肥配合施用有利于显著提高草地早熟禾草坪坪用质量。 展开更多
关键词 早熟禾 草坪 硝酸钾 坪用质量 发酵饼肥
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外施硝态氮肥对玉米苗期涝害的缓解效应 被引量:1
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作者 于秋鸿 周斌 +4 位作者 谢雨鑫 宋希云 陈子仪 孔雪晴 李军 《山东农业科学》 北大核心 2024年第1期126-132,共7页
本试验以玉米郑单958为材料,研究叶面喷施不同硝态氮肥对苗期涝害的缓解效应。结果表明,与对照(CK)相比,淹水处理(T1)第7天时幼苗株高、鲜重和干重显著降低;淹水+叶面喷施KNO3(T2)处理下幼苗地上部和根的鲜重、干重分别比T1显著增加21.7... 本试验以玉米郑单958为材料,研究叶面喷施不同硝态氮肥对苗期涝害的缓解效应。结果表明,与对照(CK)相比,淹水处理(T1)第7天时幼苗株高、鲜重和干重显著降低;淹水+叶面喷施KNO3(T2)处理下幼苗地上部和根的鲜重、干重分别比T1显著增加21.7%、45.5%和32.9%、49.6%,淹水+叶面喷施Ca(NO_(3))_(2)(T3)处理下幼苗鲜重、干重比T1略有增加。与CK相比,T1处理叶片MDA和H2O2含量第5天后均显著增加,之前也有所增加;外施硝态氮肥明显降低过氧化胁迫,第5天时T2处理叶片的MDA和H_(2)O_(2)含量分别比T1下降9.1%、14.9%,T3处理分别比T1下降2.1%和14.6%。与CK相比,T1处理叶片可溶性糖和可溶性蛋白含量略有降低,但脯氨酸含量显著增加;T2处理第1天和第5天时可溶性糖含量比T1处理显著增加44.5%和23.8%,T3处理第1天时可溶性糖含量比T1显著增加36.5%,脯氨酸含量仅在T2处理下显著增加。与CK相比,T1处理叶片抗氧化酶活性均有降低,且多半达到显著水平;外施硝态氮肥提高淹水胁迫下的抗氧化酶活性,T2处理第5天时叶片SOD、POD和CAT活性分别比T1提高25.1%、12.4%和22.1%;T3处理第5天时SOD和POD活性分别比T1提高6.4%和52.9%,但CAT活性略有下降。可见,外施KNO3比Ca(NO_(3))_(2)对涝害的缓解效应更显著。 展开更多
关键词 玉米 淹水胁迫 硝酸钾 硝酸钙
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KNO_(3)介稳区宽度的研究及初级成核动力学计算
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作者 邹洋 陆志艳 +1 位作者 胡志林 孙泽 《无机盐工业》 CAS CSCD 北大核心 2024年第9期67-74,共8页
为研究KNO_(3)在KNO_(3)-NaNO_(3)-H_(2)O中的冷却结晶过程,采用静态平衡法测量293.15~341.38 K下KNO_(3)在该体系中的溶解度,通过Apelblat方程和Van’t Hoff方程得到了溶解度与温度的关系,并计算了KNO_(3)的溶解焓和溶解熵。采用超声... 为研究KNO_(3)在KNO_(3)-NaNO_(3)-H_(2)O中的冷却结晶过程,采用静态平衡法测量293.15~341.38 K下KNO_(3)在该体系中的溶解度,通过Apelblat方程和Van’t Hoff方程得到了溶解度与温度的关系,并计算了KNO_(3)的溶解焓和溶解熵。采用超声波法研究了298.03~332.30 K下NaNO_(3)含量、搅拌速率和冷却速率对KNO_(3)介稳区宽度的影响。实验结果表明,当体系中存在NaNO_(3)时介稳区宽度变窄但影响有限。KNO_(3)介稳区宽度随搅拌速率的增加而变窄,随冷却速率增加而变宽。以KNO_(3)溶解度和溶解焓数据为基础,研究了KNO_(3)的初级成核动力学,采用自洽Nývlt型方程得到成核级数m小于3,KNO_(3)为瞬时成核,且随着饱和温度的升高,成核速率呈先增大后减小的趋势;在经典三维成核理论中,随着饱和温度的升高,成核更容易发生,当饱和温度达到一定程度后,固-液界面能γ趋于稳定。以农用硝酸钾为原料,通过冷却结晶得到高纯度KNO_(3)产品,当饱和KNO_(3)溶液由343.15 K降至298.15 K、搅拌速率为300 r/min、冷却速率为25 K/h时,添加晶种后,溶液中Na^(+)含量仅为0.0011%。 展开更多
关键词 硝酸钾 硝酸钠 介稳区 成核动力学 工业结晶
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塔里木河上游棉区土壤盐分与速效养分的空间分布及相关关系
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作者 刘昭雪 高志建 +3 位作者 白新禄 张宝月 杨莉莉 支金虎 《干旱地区农业研究》 CSCD 北大核心 2024年第3期206-213,共8页
土壤盐渍化已成为制约塔里木河上游棉田生产的主要障碍因子。为查明塔里木河上游棉田土壤盐分现状以及盐分与土壤速效养分之间的关系,建立盐渍化土壤合理施肥理论标准,提高盐渍化土壤棉花生产能力,采用克里金插值、相关性分析等方法对... 土壤盐渍化已成为制约塔里木河上游棉田生产的主要障碍因子。为查明塔里木河上游棉田土壤盐分现状以及盐分与土壤速效养分之间的关系,建立盐渍化土壤合理施肥理论标准,提高盐渍化土壤棉花生产能力,采用克里金插值、相关性分析等方法对研究区棉田土壤盐分与速效养分的累积量、分布规律及其相关关系进行研究。结果表明:塔里木河上游棉区棉田0~200 cm土层土壤全盐、硝态氮、速效磷、速效钾含量分别为1.17~2.44 g·kg^(-1)、18.9~65.1 mg·kg^(-1)、1.3~31.2 mg·kg^(-1)、64.9~107.9 mg·kg^(-1)。其中,盐分离子主要以Ca^(2+)、Na^(+)和SO^(2-)_(4)为主,0~40 cm土壤硝态氮、速效钾含量与全盐含量呈显著正相关关系,且0~40 cm土壤硝态氮、速效钾含量与全盐含量空间分布较为一致,说明施肥可以影响塔里木河上游棉田土壤盐分含量。因此,建议在生产过程中应合理施肥,以避免加重土壤盐渍化问题。 展开更多
关键词 盐分离子 硝态氮 速效钾 速效磷 空间分布
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点火药的研究进展与展望
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作者 李登科 乔秀泉 +5 位作者 成闻川 张涵 董文帅 李志敏 于琪瑶 张建国 《火工品》 CAS CSCD 北大核心 2024年第4期1-11,I0002,共12页
作为武器系统的重要组成部分,点火系统的性能直接影响到武器的发射效率和作战效果,因而点火药的性能尤为重要。以硼/硝酸钾为代表的非金属类点火药的研究已经较为深入,但该点火药面临着点火温度过高、硼粉老化及吸湿等问题。以金属粉作... 作为武器系统的重要组成部分,点火系统的性能直接影响到武器的发射效率和作战效果,因而点火药的性能尤为重要。以硼/硝酸钾为代表的非金属类点火药的研究已经较为深入,但该点火药面临着点火温度过高、硼粉老化及吸湿等问题。以金属粉作为可燃剂的金属类点火药具有高能量密度、良好的机械性能和独特的能量释放特性,但燃烧速率较慢。因此,研究人员进行了大量实验研究,制备出具有层状或核壳结构的反应材料,可以大大增加氧化剂和金属燃料之间的接触面积,并缩短传质距离,从而提高反应效率。近年来,含能配合物类点火药的研究成为本领域的研究热点,研究表明以含能配合物作为燃料,设计点火药配方,能够显著实现点火药的性能调控性能。 展开更多
关键词 点火药 硼/硝酸钾 镁/聚四氟乙烯 含能配合物 展望
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银染高尔基染色法用于神经元完整结构成像
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作者 周峰 蔡小青 +3 位作者 汤乔伟 诸颖 王丽华 胡钧 《应用化学》 CAS CSCD 北大核心 2024年第5期677-686,共10页
高尔基染色是神经元树突和树突棘可视化的经典方法,目前仍被广泛用于神经元形态可视化。银高尔基染色目前存在易产生黑色沉淀、染色神经元形态结构不完整等问题。对重铬酸钾(K_(2)Cr_(2)O_(7))和硝酸银(AgNO_(3))如何影响银染高尔基染... 高尔基染色是神经元树突和树突棘可视化的经典方法,目前仍被广泛用于神经元形态可视化。银高尔基染色目前存在易产生黑色沉淀、染色神经元形态结构不完整等问题。对重铬酸钾(K_(2)Cr_(2)O_(7))和硝酸银(AgNO_(3))如何影响银染高尔基染色方法的染色效果进行了研究,通过研究染色液组成成分重铬酸钾、硝酸银质量浓度变化和组分的不同作用方式,实现了对银染高尔基染色方法的优化。结果表明,35 mg/mL多聚甲醛(Paraformaldehyde,PFA)和20 mg/mL K_(2)Cr_(2)O_(7)混合液染色效果要明显优于20 mg/mL K_(2)Cr_(2)O_(7)单独染色效果,在K_(2)Cr_(2)O_(7)的质量浓度优化过程中,80 mg/mL K_(2)Cr_(2)O_(7)的染色效果最佳,35 mg/mL PFA与20 mg/mL K_(2)Cr_(2)O_(7)混合溶液和80 mg/mL K_(2)Cr_(2)O_(7)最佳染色时长比为3∶1,染色过程中AgNO_(3)的最佳质量浓度为10 mg/mL,在最终的染色液组成成分以及作用方式中40 mg/mL PFA固定2 d、35 mg/mL PFA和20 mg/mL K_(2)Cr_(2)O_(7)混合溶液处理3 d、80 mg/mL K_(2)Cr_(2)O_(7)处理1 d和10 mg/mL AgNO_(3)处理5 d对脑组织神经元形态的可视化具有最佳效果。优化后的银染高尔基染色方法可实现对神经元的完整形态结构染色,同时在染色过程也将产生更少的成像杂质沉淀噪点。该工作将提供一种新的高尔基改良染色方法,实现神经元完整形态结构的染色,有望为研究脑神经元结构变化与脑疾病之间的关系提供新的染色方法。 展开更多
关键词 重铬酸钾 硝酸银 神经元形态 银染高尔基染色
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基于RPM和SPM的辐射探测技术在危险品伪瞒报检测中的应用
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作者 战俭 侯永明 +3 位作者 缪利 李永 闵伟锋 史建峰 《核电子学与探测技术》 CAS 北大核心 2024年第5期806-814,共9页
以海关监管查发硝酸钾、烟花爆竹伪瞒报进出口走私为例,讨论了基于RPM和SPM设备的辐射探测技术及其在检测具有放射性属性危险品中的应用。研究结果表明,基于RPM和SPM检测的硝酸钾与烟花爆竹的辐射计数率特征与申报货物的辐射特征不一致... 以海关监管查发硝酸钾、烟花爆竹伪瞒报进出口走私为例,讨论了基于RPM和SPM设备的辐射探测技术及其在检测具有放射性属性危险品中的应用。研究结果表明,基于RPM和SPM检测的硝酸钾与烟花爆竹的辐射计数率特征与申报货物的辐射特征不一致,以此可以判断存在伪瞒报嫌疑。设备对硝酸钾的活度响应可以超过RPM和SPM设备报警阈值,最大净计数率增加为216.4%,并且SPM设备可以在短时间内正确识别出核素40K。烟花爆竹中鞭炮药放射性相对较低,四批查发货物中,最大净计数率增加为19.9%,可以触发RPM设备高报警阈值,但SPM设备无法在短时间内识别出核素。通过合理设置设备报警阈值,辐射探测技术可以作为有效的技术手段,应用于海关打击危险品伪瞒报走私。 展开更多
关键词 危险品 硝酸钾 烟花爆竹 辐射探测
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反渗透技术在离子交换法硝酸钾生产中的应用 被引量:1
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作者 邓文 曹得玉 《盐科学与化工》 CAS 2024年第2期48-51,共4页
为提高离子交换法生产硝酸钾过程中产生的氯化铵溶液进入氯化氨盐田的浓度,利用反渗透技术将收集平均浓度为15 g/L的低浓度氯化铵溶液依次经过保安过滤器、高压泵再进入一级反渗透本体装置浓缩,得到反渗透浓缩液和产水。浓缩液排入氯化... 为提高离子交换法生产硝酸钾过程中产生的氯化铵溶液进入氯化氨盐田的浓度,利用反渗透技术将收集平均浓度为15 g/L的低浓度氯化铵溶液依次经过保安过滤器、高压泵再进入一级反渗透本体装置浓缩,得到反渗透浓缩液和产水。浓缩液排入氯化铵盐田滩晒;产水再进入二级反渗透脱盐处理,得到脱盐水供生产使用。反渗透技术在离子交换法硝酸钾生产中的应用,既提高了氯化铵溶液进入盐田的整体浓度,也回收了脱盐水并用于生产使用,同时降低了生产成本,提高了生产效率。 展开更多
关键词 硝酸钾 氯化铵溶液 反渗透装置 浓缩 脱盐水
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