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A simplified ratiometric fluorescent sensing strategy for enhanced detection of alkaline phosphatase employing Prussian blue nanozymes and commercially available chromogen
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作者 Mingyue Luo Kehui Zhang +5 位作者 Honghong Rao Jianying Li Xin Xue Panpan Sun Xiaoquan Lu Zhonghua Xue 《Chinese Chemical Letters》 2025年第9期413-418,共6页
The traditional nanozymes-based ratiometric fluorescence sensing platforms usually necessitate the supplementary addition of fluorescent probes,therefore greatly restricting its convenient and broad application.In thi... The traditional nanozymes-based ratiometric fluorescence sensing platforms usually necessitate the supplementary addition of fluorescent probes,therefore greatly restricting its convenient and broad application.In this study,a highly sensitive and selective ratiometric fluorescence platform for alkaline phosphatase(ALP)detection was established,only employing Prussian blue(PB)nanozymes and a commercially available chromogen of o-phenylenediamine(OPD).PB nanozymes with remarkable peroxidaselike(POD-like)activity can effectively catalyze OPD chromogen to yield 2,3-diaminophenazine(OPDox)with an intense yellow fluorescence at 573 nm emission peak.Target ALP can facilitate ascorbic acid 2-phosphate(AAP)dephosphorylation to generate phosphate and ascorbic acid(AA).Significantly,both these two resultant hydrolysis products could effectively decrease the OPDox generation via a dualpath based inhibition on the PB nanozymes POD-like activity.On the other hand,the generated dehydroascorbic acid(DHAA)from AA oxidation would exclusively react with OPD chromogen to yield3-(dihydroxyethyl)furo[3,4-b]quinoxaline-1-one(DFQ)with a strong blue fluorescent signal at 434nm,which further providing a significant enhancement on the sensing selectivity of ALP detection.As a result,an increased yellow fluorescence of OPDox and decreased blue fluorescence of DFQ could be clearly observed with different ALP addition.A robust linear relationship between the fluorescence ratio of F_(434)/F_(573)and ALP activity ranging from 0.25U/L to 6U/L was obtained,with a low detection limit of 0.112 U/L.This proposed method demonstrates high sensitivity,excellent selectivity,cost-effectiveness,and operational simplicity,yet enabling an effective detection of ALP levels in human serum. 展开更多
关键词 Ratiometric fluorescence Prussian blue nanozymes Peroxidase-like activity Commercially available chromogens Alkaline phosphatase
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Global distributions and long-term trends of available wave energy based on ERA5 wave reanalysis
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作者 Jian Shi Wei Liu +5 位作者 Haifei Sun Xiangming Cao Yuan Li Chi Zhang Nguyen Viet Thanh Lipeng Zhang 《Acta Oceanologica Sinica》 2025年第6期15-32,共18页
Using the ERA5 wave reanalysis,the distributions and trends of global available wave energy storage during 1980−2019 are analyzed.The results show that the available wave energy storage is not only related to total wa... Using the ERA5 wave reanalysis,the distributions and trends of global available wave energy storage during 1980−2019 are analyzed.The results show that the available wave energy storage is not only related to total wave energy storage but is also affected by the local available wave probability.Different distributions and trends between the available wave energy and total wave energy storage are observed.Larger values of total wave energy storage are concentrated in the high-latitude westerlies zone,whereas available wave energy storage exhibits greater concentration in the middle-low latitude regions.In each basin,there is a notable upward trend in both total wave energy storage and available wave energy storage.However,the northern Hemisphere(NH)exhibits an increasing trend in available wave probability,whereas the southern Hemisphere(SH)experiences a decreasing trend.This divergence contributes to the spatial distributions of available wave energy storage becoming increasingly uniform.These trends in wave energy are primarily influenced by changes in significant wave height.Although the increasing trend of significant wave height across all frequency ranges induces the growth of total wave energy storage,only the increasing of wave heights falling in 1.3−4 m can cause the growth of available wave energy storage.The consistent increasing rates of wave height under different mean levels contribute to the divergent trends in available wave probability. 展开更多
关键词 ERA5 available wave energy spatial distribution long-term trends wave energy converter
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加温对聚维酮碘消毒效力和患者舒适度的影响
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作者 朱佩兰 金敏莉 +1 位作者 张雪青 孙莲莲 《中国现代医生》 2026年第1期51-54,共4页
目的探讨适度加温对聚维酮碘有效碘含量及杀菌效果和患者舒适度的影响。方法以室温(22℃)5%聚维酮碘为对照组,分别加温至25℃、30℃、35℃、40℃和45℃的5%聚维酮碘为实验组,每个温度维持1h后用0.1mol/L硫代硫酸钠溶液进行滴定,测定各... 目的探讨适度加温对聚维酮碘有效碘含量及杀菌效果和患者舒适度的影响。方法以室温(22℃)5%聚维酮碘为对照组,分别加温至25℃、30℃、35℃、40℃和45℃的5%聚维酮碘为实验组,每个温度维持1h后用0.1mol/L硫代硫酸钠溶液进行滴定,测定各组的有效碘含量;采用悬液定量杀菌实验测定不同温度聚维酮碘对金黄色葡萄球菌、大肠埃希菌和白念珠菌的杀菌对数值。基于上述实验结果,选用最接近体温的35℃5%聚维酮碘(加温组)与室温5%聚维酮碘(常温组)进行皮肤消毒后采样培养,比较两组的消毒合格率、体温变化及寒战发生率。结果25℃、30℃、35℃、40℃组的有效碘浓度显著高于22℃组(P<0.05),且在35℃时达到峰值,45℃时回落至室温水平。不同温度5%聚维酮碘作用3min后,对金黄色葡萄球菌、大肠埃希菌、白念珠菌的杀菌对数值均>5.0,杀菌率均为100%。常温组和加温组的皮肤消毒合格率均为100%。消毒后15min、手术结束时,加温组患者的体温均显著高于常温组(P<0.05),加温组患者术中低体温发生率显著低于常温组(P<0.05)。加温组患者的寒战发生率显著低于常温组(χ^(2)=11.540,P=0.021)。结论适当加温可提高聚维酮碘的有效碘含量,且不影响其消毒效果。使用35℃的聚维酮碘进行皮肤消毒,有助于维持患者术中体温稳定,降低低体温与寒战的发生风险,从而提升手术患者的舒适度与安全性。 展开更多
关键词 聚维酮碘 有效碘含量 金黄色葡萄球菌 大肠埃希菌 白念珠菌 消毒效力
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Available parking space occupancy change characteristics and short-term forecasting model 被引量:6
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作者 季彦婕 王炜 邓卫 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期604-608,共5页
Based on an available parking space occupancy (APSO) survey conducted in Nanjing, China, an APSO forecasting model is proposed. The APSO survey results indicate that the time series of APSO with different time-secti... Based on an available parking space occupancy (APSO) survey conducted in Nanjing, China, an APSO forecasting model is proposed. The APSO survey results indicate that the time series of APSO with different time-sections are periodical and self-similar, and the fluctuation of the APSO increases with the decrease in time-sections. Taking the short-time change behavior into account, an APSO forecasting model combined wavelet analysis and a weighted Markov chain is presented. In this model, an original APSO time series is first decomposed by wavelet analysis, and the results include low frequency signals representing the basic trends of APSO and several high frequency signals representing disturbances of the APSO. Then different Markov models are used to forecast the changes of low and high frequency signals, respectively. Finally, integrating the predicted results induces the final forecasted APSO. A case study verifies the applicability of the proposed model. The comparisons between measured and forecasted results show that the model is a competent model and its accuracy relies on real-time update of the APSO database. 展开更多
关键词 available parking space occupancy change characteristics short-term forecasting wavelet analysis weighted Markov chain
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Available Contents of Trace Nutrient Element and Factors Affecting Their Availability in Western Jilin 被引量:5
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作者 施宪 王冬艳 +2 位作者 李月芬 靳克 郭珍 《Agricultural Science & Technology》 CAS 2010年第5期73-76,共4页
Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient ele... Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient elements and their affecting factors are studied. The results show that the available B in western Jilin is in a middle level,the content in Nong'an is higher than that in the others; the available Mn is extremely abundant; the available Cu in Nong'an is obviously higher than other areas,and the content in Da'an differs greatly; the available Zn is in a middle level; the severe shortage of available Mo differs between different areas; and the available Fe is extremely abundant. The available Mn,Cu and Fe have significantly positive correlation with their total content; the available B has significantly positive correlation with pH,and Zn has obviously negative correlation with pH; the available Mn and Fe had significantly positive correlation with soil organic matter. 展开更多
关键词 Trace nutrient element available content The affecting factors Western Jilin
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聚磷酸掺混磷肥减量施用对滴灌棉花产量和磷素利用效率的影响
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作者 崔玉满 江席亮 +5 位作者 范守杰 杨昌南 许世武 马伟栋 危常州 张新疆 《核农学报》 北大核心 2026年第1期194-202,共9页
为探究3种聚磷酸掺混磷肥减量施用对滴灌棉花生长和产量形成的影响,本研究将聚磷酸铵1掺混磷肥(APP1)、聚磷酸铵2掺混磷肥(APP2)、三聚磷酸钾掺混磷肥(KTPP)以及常规滴灌二铵(DAP)作为磷源,分别设置常规施磷(P_(120),P_(2)O_(5)120 kg&#... 为探究3种聚磷酸掺混磷肥减量施用对滴灌棉花生长和产量形成的影响,本研究将聚磷酸铵1掺混磷肥(APP1)、聚磷酸铵2掺混磷肥(APP2)、三聚磷酸钾掺混磷肥(KTPP)以及常规滴灌二铵(DAP)作为磷源,分别设置常规施磷(P_(120),P_(2)O_(5)120 kg·hm^(-2))、磷肥减施10%(P_(108),P_(2)O_(5)108 kg·hm^(-2))、磷肥减施20%(P_(96),P_(2)O_(5)96 kg·hm^(-2))和不施磷处理(P_(0)),于棉花蕾期、盛花期及盛铃期测定0~20和20~40 cm土层土壤速效磷含量,盛花期和盛铃期测定生物量、磷吸收量和结铃动态,成熟期测定产量及产量构成。结果表明,地上部生物量和磷吸收量及结铃数、土壤速效磷含量均随施磷量的减少而下降,单铃重则随施磷量的减少而增加。同一施磷量下,在蕾期、盛花期及盛铃期,APP2在0~20 cm土层的土壤速效磷含量高于其他磷源;在盛花期和盛铃期,APP2的生物量和磷吸收量高于其他磷源。同一施磷量下,APP2和KTPP处理结铃数显著高于DAP,而APP1与DAP间差异不显著。APP2磷源处理下的籽棉产量、产投比、磷肥农学利用率均表现为P108>P120>P96>P0。综上所述,聚磷酸铵2掺混磷肥以108 kg·hm^(-2)施用可兼顾产量及磷肥高效利用。本研究结果为新疆滴灌磷肥减施增效提供了参考。 展开更多
关键词 棉花 聚磷酸盐 产投比 土壤速效磷
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Spatial Variation Characteristics of Soil Available Plumbum (Pb) in Vegetable Bases in Urumqi City 被引量:1
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作者 郑江 王灵 《Agricultural Science & Technology》 CAS 2012年第1期155-157,167,共4页
[Objective] The paper was to study the spatial variation characteristics of soil available plumbum (Pb) in vegetable bases of Urumqi City. [Method] With the vegetable base in northern suburb of Urumqi city as a typi... [Objective] The paper was to study the spatial variation characteristics of soil available plumbum (Pb) in vegetable bases of Urumqi City. [Method] With the vegetable base in northern suburb of Urumqi city as a typical area, the structure feature of soil available Pb content in suburb of oasis city in the arid area was ana- lyzed to get the spatial distribution pattern of available Pb, the origin and pollution source of this distribution pattern were also revealed. [Result] The available Pb in vegetable base of northern suburb in Urumqi City belonged to moderate variation. Semivariance model fitting showed that available Pb content could be fit with expo- nential function, which had spatial correlation within a certain range. The spatial dis- tribution pattern of available Pb content was obtained by using optimal Kriging inter- polation, and indicated that soil available Pb content was closely related to industrial activities, sewage irrigation and atmospheric dust. [Conclusion] The study provided the scientific basis for recognition, pollution risk assessment and pollution control of Pb pollution sources in the region, which have great significance on creating safe and clean production environment and selecting reasonable vegetable planting districts. 展开更多
关键词 URUMQI Soil Pb available state Spatial variation
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Influence of Phosphorus Fertilizer Application on Available Phosphorus and Easy-loss Phosphorus Content in Red Soil
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作者 赵牧秋 陈欣 史云峰 《Agricultural Science & Technology》 CAS 2012年第3期570-573,577,共5页
[Objective] This study was to investigate the influence of phosphorus (P) fertilizer application on available P and easy-loss P content in red soil under aerobic incubating condition, with the aim to provide theoret... [Objective] This study was to investigate the influence of phosphorus (P) fertilizer application on available P and easy-loss P content in red soil under aerobic incubating condition, with the aim to provide theoretical basis for the management of elemental P and evaluation of elemental P loss potential. [Method] Totally six treat- ments were set to the soil samples. The Olsen-P, Bray-1 P and CaCl2-P contents of each soil sample were measured after indoor aerobic incubation. [Result] In the red soil of different P fertilizer application rates, the Olsen-P content decreased with the increasing of incubation time, while the content of Bray-1 P increased and CaCI2-P content was first increased then decreased. CaCl2-P content was linear correlated with Olsen-P content and Bray-1 P content. About 62% P fertilizers were transformed into Bray-1 P pool, and 14% into Olsen-P pool, but only 0.12% transformed into CaCl2-P pool. [Conclusion] There is little risk of P loss caused by P fertilizer application under aerobic condition, but it would increase with the increasing application dose, and the most serious time is the primeval period after P fertilizer application. 展开更多
关键词 Phosphorus fertilizer available phosphorus Red soil INCUBATION
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补播模式对喀斯特地区草地土壤养分和酶化学计量特征的影响
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作者 冯阳 高小叶 +3 位作者 杨学东 王春梅 罗彬 张涛 《草地学报》 北大核心 2026年第1期87-97,共11页
为探究补播模式对退化草地土壤养分和酶化学计量特征的影响,以贵州独山退化草地为研究对象,以退化草地(CK)为对照,设置燕麦(Avena sativa L.)+黑麦草(Lolium perenne L.)(AL)和燕麦+黑麦草+三叶草(Trifolium L.)(ALT)补播2个处理。结果... 为探究补播模式对退化草地土壤养分和酶化学计量特征的影响,以贵州独山退化草地为研究对象,以退化草地(CK)为对照,设置燕麦(Avena sativa L.)+黑麦草(Lolium perenne L.)(AL)和燕麦+黑麦草+三叶草(Trifolium L.)(ALT)补播2个处理。结果表明:AL和ALT显著增加0~10 cm土层有机碳、全氮和速效磷含量,增幅分别为42.66%和57.29%、75.54%和116.30%、90.78%和155.59%。ALT处理下0~10 cm土层C/N显著降低,N/P提高,缓解了土壤氮缺乏;β-1,4-葡萄糖苷酶和β-1,4-N-乙酰葡糖氨糖苷酶活性分别显著增加182.21%和186.85%,且增幅高于AL。ALT显著增加0~10 cm土层酶的矢量长度,加剧了微生物碳限制。相关分析表明,胞外酶活性主要受全氮和有机碳的共同调控。综上,该区域选择ALT补播模式可有效提高退化草地土壤有机碳和有效养分,缓解氮缺乏,提高土壤碳、氮循环相关酶活性,但是增强了表层土壤微生物的碳限制。 展开更多
关键词 豆科 退化草地 可利用养分 胞外酶活性
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Effects of Nitrogen Fertilization Amount on the Prophase Yield of Phaseolus vulgaris and Available Nitrogen Content of Soil
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作者 汤国民 于立芝 《Agricultural Science & Technology》 CAS 2016年第8期1889-1891,共3页
[Objective] This study aimed to provide certain scientific basis for reasonable application of nitrogen fertilizer in the pollution-free cultivation of Phaseolus vulgaris. [Method] A field experiment was conducted to ... [Objective] This study aimed to provide certain scientific basis for reasonable application of nitrogen fertilizer in the pollution-free cultivation of Phaseolus vulgaris. [Method] A field experiment was conducted to investigate the effects of different nitrogen fertilization amounts on the prophase yield and economic efficiency of P. vulgaris and available nitrogen content of soil. [Result] With the increased application amount of nitrogen fertilizer, the prophase yield and economic efficiency of P. vulgaris reached the peaks in the Treatment 3 (8 690.48 kg/ hm^2 and 32 222 yuan/hm^2), and significant differences were found among different treatment groups. With the increased nitrogen fertilization amount, the soil available nitrogen content increased, showing a positive correlation with correlation coefficient of 0.856 5. Excess nitrogen fertilizer reduced the prophase yield and economic efficiency of P. vulgaris. For the open field cultivation of P. vulgaris, the optimum application amount of nitrogen fertilizer was 178 kg/hm^2. [Conclusion] Application of nitrogen fertilizer could effectively increase the soil available nitrogen content. 展开更多
关键词 Nitrogen fertilizer Phaseolus-vulgaris Prophase yield Soil available nitrogen
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电感耦合等离子体质谱(ICP-MS)法测定高盐高有机质土壤中速效钾和缓效钾
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作者 左修源 孙兆楠 +1 位作者 李雨蒙 贾雷 《中国无机分析化学》 北大核心 2026年第1期116-125,共10页
土壤中速效钾和缓效钾的精准测定是评估土壤供钾能力、指导科学施肥及保障农业可持续发展的重要基础,但高盐、高有机质土壤因基质复杂,传统分析方法面临显著挑战,需建立高效、灵敏且抗干扰的检测技术。通过研究不同提取剂、提取时间、... 土壤中速效钾和缓效钾的精准测定是评估土壤供钾能力、指导科学施肥及保障农业可持续发展的重要基础,但高盐、高有机质土壤因基质复杂,传统分析方法面临显著挑战,需建立高效、灵敏且抗干扰的检测技术。通过研究不同提取剂、提取时间、提取温度对速效钾的影响,以及不同消解体系、仪器条件优化和内标选择等因素对缓效钾的影响。实验结果表明:提取剂为醋酸铵-乙二胺四乙酸,提取温度为30℃,提取时间为40 min能够准确测定速效钾;HNO_(3)+HF+H_(2)O_(2)+HClO_(4)=5∶2∶1∶0.5为消解体系,通过微波消解能准确测定缓效钾;且速效钾检出限0.05 mg/kg、定量限0.15 mg/kg、相关系数0.9996、加标回收率94.1%~98.2%、精密度2.8%~3.9%;缓效钾检出限0.16 mg/kg、定量限0.48 mg/kg、相关系数0.9993、加标回收率91.3%~96.5%、精密度3.2%~4.5%。该方法具有灵敏度高、抗干扰性强、准确度高等优势,满足高盐高有机质土壤中速效钾与缓效钾的测定需求,为土壤三普的测试提供了技术支持,还为复杂基质土壤的钾素形态研究、农业精准管理及生态修复提供了可靠的技术支撑,具有显著的科研价值与实践意义。 展开更多
关键词 土壤 电感耦合等离子体质谱 速效钾 缓效钾 方法优化
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Effects of Growing of Different Types of Crops on Constitution of Soil Available Nitrogen and Conversion and Utilization of Nitrogen Fertilizer
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作者 曾科 杨兰芳 +2 位作者 于婧 李彬波 汪正祥 《Agricultural Science & Technology》 CAS 2017年第6期1067-1071,1075,共6页
The soybean, cotton, maize and sorghum were planted in pot under low nitrogen, high nitrogen treatments, the soil available nitrogen constitution and con- version and utilization of nitrogen fertilizer were determined... The soybean, cotton, maize and sorghum were planted in pot under low nitrogen, high nitrogen treatments, the soil available nitrogen constitution and con- version and utilization of nitrogen fertilizer were determined, so as to provide techni- cal guidance for reasonable use and improving use efficiency of nitrogen fertilizer for different types of crops. Compared with the control with nitrogen but unplanted crop, growing soybean, cotton, maize, sorghum significantly decreased the soil available N contents by 53. 48%, 51.54%, 33.10%, 55.03%,and influenced the constitution of soil available N. Thereinto, growing soybean, cotton, maize and sorghum significantly decreased soil inorganic N contents by 85.41%, 83.09%, 70.89% and 83.35%,but increased soil hydrolysable organic N contents by 1.41, 1.53, 2.11 and 1.28 times, respectively; growing soybean, cotton, maize and sorghum significantly decreased the rate of soil inorganic N to available N by 68.61%, 65.09%, 56.47% and 63.00%, but increased the rate of soil hydrolysable organic N to available N by 4.18, 4.21, 3.66 and 4.08 times, respectively. Compared with the control, growing soybean, cotton, maize and sorghum significantly increased the transform rate of ammonium nitrogen fertilizer by 93.66%, 38.19%, 32.58% and 38.31% respectively, and growing soybean treatment had the highest increasing range; the nitrification rates of ammo- nium nitrogen fertilizer of growing soybean, cotton, maize and sorghum treatments were negative values, and growing soybean treatment had the highest decreasing amplitude. The ammonium nitrogen fertilizer use efficiency of growing soybean, cot- ton, maize and sorghum treatments were 52.01%, 28.31%, 24.16% and 28.40% re- spectively and growing soybean treatment had the highest value. In conclusion, growing crops suppressed the soil nitrification and accelerated the development of soil hydrolysable organic nitrogen by the utilization of soil available nitrogen and the alteration of soil environment, and hence impacted the constitution of soil available nitrogen and the transform and use of ammonium nitrogen applied in soil. Legumi- nous crops had stronger ability of suppressing nitrification, making use of ammonium compared with non-Leguminous crops. 展开更多
关键词 Growing of crops available nitrogen Ammonium nitrogen Nitrate nitro-gen Hydrolysable organic nitrogen Nitrogen fertilizer use efficiency
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低分子有机酸对滨海盐化潮土磷吸附-解吸特性和磷形态的影响
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作者 坤燕 杨康 +5 位作者 孙瑞 封乾 刘淑桥 郑雅文 李晓欣 胡春胜 《中国生态农业学报(中英文)》 北大核心 2026年第1期132-145,共14页
环渤海滨海盐碱地富含碳酸钙等石灰质成分,pH>8,土壤磷素极易被吸附或转化为难溶的磷酸钙盐。低分子有机酸是植物和微生物的重要活化磷策略,其中草酸和柠檬酸的磷活化效果最好,且在土壤中广泛存在,但关于它们在滨海盐碱地中作用机理... 环渤海滨海盐碱地富含碳酸钙等石灰质成分,pH>8,土壤磷素极易被吸附或转化为难溶的磷酸钙盐。低分子有机酸是植物和微生物的重要活化磷策略,其中草酸和柠檬酸的磷活化效果最好,且在土壤中广泛存在,但关于它们在滨海盐碱地中作用机理的研究较少。因此,本研究采用批量试验法和改进的Hedley磷素分级法,探究了5(C5)、10(C10)、50(C50)mmol∙kg^(−1)草酸和5(N5)、10(N10)、50(N50)mmol∙kg^(−1)柠檬酸对滨海盐化潮土磷素吸附-解吸特性和形态转化的影响。结果表明:1)草酸抑制磷素吸附和活化磷素的能力比柠檬酸强。草酸和柠檬酸均可通过—COO-与磷酸盐竞争结合位点,促进磷素的解吸与活化,草酸以阴离子作用为主,柠檬酸以质子酸作用为主。2)C50在30 d内促进了土壤稳定性无机磷(Pi)向活性Pi的转化。但N50的活化机制与以往研究不同,在短期培养(3 d)土壤中促进了活性Pi和稳定性Pi向中活性Pi的转化,使中活性Pi显著提高1.33%。各处理均有促进中活性有机磷(Po)向活性Po转化的趋势。3)C10、C50和N50可以提高土壤有效磷含量。但低分子有机酸存在时效性,在第3天解磷效果开始降低,柠檬酸第10天完全失效,草酸第30天仍有效。4)土壤对磷素的吸附-解吸能力与稀HCl提取态Pi(D.HCl-Pi)显著相关,磷素形态中NaHCO_(3)提取态Pi(NaHCO_(3)-Pi)与D.HCl-Pi显著负相关,D.HClPi是影响滨海盐化潮土磷素有效性的关键磷素形态。基于研究结果,建议环渤海滨海盐碱地中施用10~50mmol∙kg^(−1)草酸,可显著且持久地提高土壤磷活性。 展开更多
关键词 低分子有机酸 磷吸附-解吸 磷形态 有效磷 滨海盐碱地
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Analysis and Producing Causes of Available Sulphur Status quo(Rich or Insufficient) in Farmlands and Countermeasures in Dengzhou City
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作者 张有成 《Agricultural Science & Technology》 CAS 2014年第8期1348-1350,共3页
In the research, available sulphur in 4 700 soil samples was tested and analyzed in 2006-2007 in Dengzhou, and the results showed that available sulphur was insufficient in farmlands in Dengzhou for cereal crop and ab... In the research, available sulphur in 4 700 soil samples was tested and analyzed in 2006-2007 in Dengzhou, and the results showed that available sulphur was insufficient in farmlands in Dengzhou for cereal crop and about 60% farmlands with available sulphur belong to the farmlands with potential shortage of available sulphur for Cruciferae, Liliaceae and Leguminosae. Meanwhile, the producing causes were analyzed from the perspectives of fertilization structure and planting structure and the countermeasures were proposed in terms of sulphur movements in plants and characters. 展开更多
关键词 available sulphur S Rich or insufficient COUNTERMEASURES
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谈谈available在医学文献中的译法
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作者 何祖佳 《世界今日医学杂志》 2002年第9期793-794,共2页
关键词 医学文献 available 译法
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基于毛竹林地土壤高效溶磷细菌组合的复合菌肥构建及其促生机制研究
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作者 李悦 贾婧怡 +2 位作者 朱迎 沈越 史文辉 《西南林业大学学报(自然科学)》 北大核心 2026年第1期39-48,共10页
通过盆栽试验及不同载体培养接种比较试验,在毛竹苗生长季末期(T_(1))和翌年快速生长期末期(T_(2))取样进行各项指标测定,验证高效溶磷细菌菌株组合在毛竹幼苗生长过程中的功能效应,进一步构建菌株组合特异性载体,观测分析其对毛竹苗生... 通过盆栽试验及不同载体培养接种比较试验,在毛竹苗生长季末期(T_(1))和翌年快速生长期末期(T_(2))取样进行各项指标测定,验证高效溶磷细菌菌株组合在毛竹幼苗生长过程中的功能效应,进一步构建菌株组合特异性载体,观测分析其对毛竹苗生长及土壤磷养分环境的影响。结果表明:细菌组合的冻干菌剂和液体菌剂对毛竹幼苗生长和养分积累起到显著促生作用,其中液体菌剂在T_(1)时期促生效果好,根生物量和根系全氮含量分别较CK显著增加103%和15.65%;冻干菌剂在T_(2)时期促生效果好,土壤全氮含量和有效磷含量分别较CK显著增加了16.11%和1105%,总生物量及全氮全磷含量较CK显著增加91.49%、76.32%和122.58%。花生壳与甘蔗渣1∶1等体积混合适宜作为细菌组合的载体。添加该载体构建的固态溶磷细菌组合菌肥1 a后,土壤有效磷显著增加了408%;且接种处理后,T_(1)时期毛竹苗根系、地上生物量较CK分别增加8.7%和41.9%,T_(2)时期毛竹苗根系、地上生物量较CK分别增加32.3%和746%。 展开更多
关键词 土壤 有效磷 溶磷微生物 微生物 复合菌肥 幼苗
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国际履约和超低排放背景下钢铁行业二噁英协同控制技术体系研究
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作者 任志远 雷荣荣 +4 位作者 郑扬 左娆 邢奕 苏伟 胡健 《工程科学学报》 北大核心 2026年第1期214-226,共13页
钢铁行业是国民经济重要基础产业,其庞大的产能带来了高强度的能源消耗和污染物排放问题,已成为中国工业领域大气污染物的最大排放源.随着环境标准持续加严,钢铁行业已从传统单因子污染防治逐步转向多污染物超低排放与协同治理.在超低... 钢铁行业是国民经济重要基础产业,其庞大的产能带来了高强度的能源消耗和污染物排放问题,已成为中国工业领域大气污染物的最大排放源.随着环境标准持续加严,钢铁行业已从传统单因子污染防治逐步转向多污染物超低排放与协同治理.在超低排放和国际履约双重目标下,中国钢铁行业面临着综合治理常规污染物、新污染物和碳排放的复合挑战以及提升行业绿色竞争力的关键挑战.本文系统梳理了国内外钢铁行业多污染物协同控制领域的政策标准、技术体系及应用实践,中国现行排放标准在颗粒物、SO_(2)和NO_(x)等指标上已达到国际领先水平,但二噁英排放限值与国际公约和欧盟、日本等发达国家和地区尚有差距.烧结及电炉作为二噁英排放控制重点工序,应基于现行最佳可行技术体系,从原料筛选、工艺优化及多级末端治理角度,重点推广原料分选、工艺优化、高效除尘与吸附、SCR技术等多元综合治理措施,可实现二噁英与常规污染物的协同控制.未来应进一步完善钢铁行业相关技术政策标准,加强对新污染物的研究,发展在线监测技术,并利用智能化手段提升协同控制的实时精准化管理水平.同时,推动多污染物先进协同减排技术的研发与应用,探索减污降碳的耦合路径,促进钢铁行业绿色新质生产力发展. 展开更多
关键词 《斯德哥尔摩公约》 最佳可行技术 二噁英 超低排放 协同减排
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超声浸提-离心分离-电感耦合等离子体原子发射光谱(ICP-AES)法测定碱性、中性三普样品中的有效磷
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作者 胡家祯 赵冲 +6 位作者 来克冰 郭家凡 袁润蕾 陈亚杰 刘春霞 程祎 冯瑞选 《中国无机分析化学》 北大核心 2026年第1期98-107,共10页
土壤有效磷的准确测定对优化土壤肥力管理、保障农业生产效益及节约资源至关重要。本研究建立了一种基于超声提取-离心分离-电感耦合等离子体发射光谱法(ICP-AES)的土壤有效磷快速测定方法。采用0.5 mol/L NaHCO_(3)溶液浸提,通过10%硝... 土壤有效磷的准确测定对优化土壤肥力管理、保障农业生产效益及节约资源至关重要。本研究建立了一种基于超声提取-离心分离-电感耦合等离子体发射光谱法(ICP-AES)的土壤有效磷快速测定方法。采用0.5 mol/L NaHCO_(3)溶液浸提,通过10%硝酸酸化稀释消除高温产生CO_(2)的干扰,并优化了超声参数、放置时间、分离方式及仪器条件。磷浓度在0~20 mg/L与其对应的谱线强度线性相关,相关系数为0.9995;方法检出限和测定下限分别为0.35和1.40 mg/kg。使用土壤有效磷标准物质验证,测定结果(n=6)的相对标准偏差(RSD)为0.76%~6.6%,相对误差(RE)为-4.0%~2.7%。碱性及中性“三普”样品的加标回收率为95.0%~108%。采用本方法与标准方法(HJ 704—2014)对实际样品同时进行分析,检测结果基本一致。本方法具有提取速度快、自动化程度高、抗基质干扰能力强、准确度高、精密度好等优势,适用于土壤普查中大批量样品的高通量快速测定。 展开更多
关键词 超声 离心 电感耦合等离子体发射光谱法 三普 有效磷
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液压缸泄漏响应特性分析及检测方法研究
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作者 王守龙 何鹏 马骏 《科技创新与应用》 2026年第1期147-150,共4页
液压系统作为一种动力传递技术,因其具有高效、安全、易控制、驱动力大等优点得到广泛的应用。为快速找到液压系统液压缸故障原因及故障点所在位置,及时对设备故障进行维护处理,确保生产装卸作业的连续性、安全性和稳定性。通过对液压... 液压系统作为一种动力传递技术,因其具有高效、安全、易控制、驱动力大等优点得到广泛的应用。为快速找到液压系统液压缸故障原因及故障点所在位置,及时对设备故障进行维护处理,确保生产装卸作业的连续性、安全性和稳定性。通过对液压系统液压缸运用观察检查法、压力曲线法、油路通断法和应力应变法等检测方法,能有效进行故障原因分析,准确找到设备故障点,快速、高效、准确地完成维保作业,确保登船梯的可用性和完整性。 展开更多
关键词 液压系统 特性分析 检测方法 可用性 完整性
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Distribution of available soil water capacity in China 被引量:79
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作者 ZHOUWenzuo LIUGaohuan +1 位作者 PANJianjun FENGXianfeng 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期3-12,共10页
The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for m... The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for most of soil profiles and the nationwide ASWC largely remains lacking in relevant soil data in China. This work was to estimate ASWC based on physical and chemical properties and analyze the spatial distribution of ASWC in China. The pedo-transfer functions (PTFs), derived from 220 survey data of ASWC, and the empirical data of ASWC based on soil texture were applied to quantify the ASWC. GIS technology was used to develop a spatial file of ASWC in China and the spatial distribution of ASWC was also analyzed. The results showed the value of ASWC ranges from 15 × 10-2 cm3·cm-3 to 22 × 10-2 cm3·cm-3 for most soil types, and few soil types are lower than 15 × 10-2 cm3·cm-3 or higher than 22 × 10-2 cm3·cm-3. The ASWC is different according to the complex soil types and their distribution. It is higher in the east than that in the west, and the values reduce from south to north except the northeastern part of China. The "high" values of ASWC appear in southeast, northeastern mountain regions and Northeast China Plain. The relatively "high" values of ASWC appear in Sichuan basin, Huang-Huai-Hai plain and the east of Inner Mongolia. The relatively "low" values are distributed in the west and the Loess Plateau of China. The "very low" value regions are the northern Tibetan Plateau and the desertified areas in northern China. In some regions, the ASWC changes according to the complex topography and different types of soils. Though there remains precision limitation, the spatial data of ASWC derived from this study are improved on current data files of soil water retention properties for Chinese soils. This study presents basic data and analysis methods for estimation and evaluation of ASWC in China. 展开更多
关键词 available soil water capacity pedo-transfer functions China
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