Results 71 to 80 of about 681,279 (194)
World Food Policy, Volume 12, Issue 2, November 2026.ABSTRACT Household food expenditure continues to be a key factor in ensuring the realization of the Human Right to Adequate Food. Particularly in Brazil, access to food can be limited by economic constraints in vulnerable families, especially among farming families, who have been more vulnerable to food insecurity in recent years in the country.
Lucas de Almeida Moura +3 more
wiley +1 more source
, 1993 一种薏苡仁酯的提取方法，其特征在于是采用索氏提取器，以丙酮溶剂对原料进行回流抽提。同时在进行层析柱分离处理时采用碱或氨水处理的碱性氧化铝吸附剂层析柱。该工艺与目前采用的技术相比，抽取溶剂丙酮用量少，不用碱洗及用溴麝香草酚蓝指示剂处理氧化铝吸附剂。其工艺过程短，简便易行，分离效果好，产品的收率高可达０．６％，并可较大幅度降低生产成品，因此适于在工业生产中应用 ...
刘和众
core
Measuring Governance or Wealth? Construct Validation of AI Readiness Indices
Policy &Internet, Volume 18, Issue 3, September 2026.ABSTRACT Many are the promises of artificial intelligence and the indices claiming to measure government readiness for it. This study provides the first construct validity investigation of the Oxford Insights Government AI Readiness Index, the Tortoise Global AI Index, and the IMF AI Preparedness Index, using a nine‐test battery and drawing on ...
Anis Ben Brik
wiley +1 more source
Zhejiang Daxue xuebao. Lixue ban, 2009 研究了紫心甘薯总黄酮的微波提取工艺及其抗氧化活性.以芦丁为标准品,通过选用L9(34)正交表设计实验,确立提取总黄酮的最佳条件并以VC为对照品,采用DPPH •（二苯代苦味酰自由基）法研究提取物的抗氧化活性.紫心甘薯总黄酮的最佳提取条件为：乙醇浓度70%,提取温度80 ℃,料液比1 ：20,提取时间35 min；测得紫心甘薯薯肉和薯皮中总黄酮含量分别为1.55%和3.30%,二者抗氧化活性以半数抑制浓度(IC50)表示分别为0.020 4 ,0.019 2mg •mL-1 ...
GAOLi-wei(高丽威) +1 more
doaj +1 more source
Rare Metals, Volume 45, Issue 9, September 2026.ABSTRACT Rationally selection of precursor additives during perovskite crystallization is essential for obtaining high‐quality films and achieving high‐performance perovskite solar cells (PSCs). However, the discovery and optimization of effective additives still rely heavily on time‐consuming and costly trial‐and‐error experiments.
Zhimin Feng +12 more
wiley +1 more source
, 1995 本发明属于中药薏苡仁提取物经加工制取的注射液和霜剂新应用领域。其特征是所制成的注射液和霜剂可用于治疗癌症和皮肤顽症。使用它针对癌症和皮肤病的治疗取得了显著的疗效，临床结果表明绝大多数症状在半月至一月内可获痊愈。它具有疗效高，安全无毒副作用等优点。可成为一种抗癌和治疗皮肤病的药物 ...
刘和众
core
Rare Metals, Volume 45, Issue 9, September 2026.ABSTRACT In MAX‐phase‐derived metal–matrix composites, the M‐site element simultaneously governs carbide chemistry and matrix precipitate stability, yet it has traditionally been selected empirically rather than from a predictive criterion linking M‐site choice to carbide chemistry, matrix alloying, and L12 stability; moreover, the reaction pathway ...
Wei Yang +8 more
wiley +1 more source
, 2007 本发明属于生物工程领域。针对目前天然脱落酸 提取率和纯度不高的问题，本发明公开了一种天然脱落酸的提 取方法，通过发酵液酸化后过滤，大孔吸附树脂吸附后洗脱， 洗脱液经浓缩后进行萃取，萃取液浓缩得到结晶粗品；结晶粗品溶解后，用硅胶吸附杂质，加入己烷或苯或石油醚或四氯化碳结晶助剂，减压浓缩，冷却结晶，洗涤、真空干燥，制得95 ％以上天然脱落酸结晶体，本方法具有提取率高 ...
周金燕, 谭红, 杨杰, 李志东
core
Risk, Hazards &Crisis in Public Policy, Volume 17, Issue 3, September 2026.ABSTRACT Disasters and crises disrupt lives and test the capacities of governments and organizations. While their immediate aftermath is often marked by uncertainty and disruption, recurrent patterns in how individuals are affected give rise to foreseeable hardships.
Michel L. A. Dückers
wiley +1 more source
, 2000 为了改变我国海藻多糖依靠水煮及乙醇沉淀法的落后现状，研究开发新的海藻多糖提取分离方法，在海洋863青年基金项目819-Q-15的支持下，本论文以以海带为原料，在浸提方面研究了气升式循环超声破碎浸提工艺及装置；在海藻硫酸酯多糖提取方面进行了絮凝分离和外加电场强化絮凝分离的研究；在分离方面进行了溶剂萃取研究。实验中采用了超声波破碎的方法破碎海带颗粒，从中提取海带多糖。实验所用装置为自制1.2升、8升气升式超声浸提装置。研究结果表明：在1.2升浸提装置中，颗粒的粒度提取率的影响是：随颗粒粒度的增大，提取率下降；
黄猛
core