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排序方式: 共有378条查询结果,搜索用时 15 毫秒
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Seven strains of Beauveria bassiana were evaluated for their effects on the eggs of Lasioderma serricorne under laboratory conditions. Strains were applied at a single dose of 0.03 g conidia kg−1 of grain = 2 × 109 conidia g−1 of kaolin kg−1 of grain. All strains were pathogenic on the eggs of L. serricorne. Two strains, MS-8, and 7284, caused the highest levels of egg mortality. These two strains were then formulated at a fixed dose of 0.03 g conidia, with kaolin as an active carrier, at doses of 0.0, 0.5 g, 1 g, 2 g and 3 g of kaolin kg−1 of grain. These powder formulations were evaluated for their effects on adult mortality, larval mortality, number of adults emerged, level of grain damaged and level of weight loss on rice grains. The highest levels of adult mortality and larval mortality were caused by Strain MS-8 at a kaolin dose of 3 g kg−1. It also caused the lowest levels of adult emerged (10%), grain damaged (1.07%) and weight loss (0.55%). When unformulated, the same dose of conidia performed poorly for the same parameters (64%; 20.2%; 3.37%). The highest levels of grain damaged (27%) and weight loss (6.04%) were observed in the untreated control (UTC). Observations made with a scanning electron microscope (SEM) showed that unformulated conidia clumped together whereas conidia formulated in kaolin remained as discrete conidia. 相似文献
3.
《International Journal of Hydrogen Energy》2019,44(8):4188-4196
Exploring and designing efficient non-noble catalysts formed by element doping and nanostructure modification for the hydrogen evolution reaction (HER) is of critical importance with respect to sustainable resources. Herein, we have prepared a three-dimensional binary NiCo phosphide with hierarchical architecture (HA) composed of NiCoP nanosheets and nanowires grown on carbon cloth (CC) via a facile hydrothermal method followed by oxidation and phosphorization. Due to its unique hierarchical nanostructure, the NiCoP HA/CC electrocatalyst exhibits excellent performance and good working stability for the HER in both acidic and alkaline conditions. The obtained NiCoP HA/CC shows excellent HER activity with a low potential of 74 and 89 mV at 10 mA cm−2, a small Tafel slope of 77.2 and 99.8 mV dec−1 and long-term stability up to 24 h in acidic and alkaline electrolyte, respectively. NiCoP HA/CC, a non-noble metal material, is a promising electrocatalyst to replace noble metal-based electrocatalysts for the HER. 相似文献
4.
《Food Control》2014,35(2):457-465
In this study, we investigated the presence of 19 different agricultural pesticides in 210 samples of eight types of domestic vegetables collected from several vegetable-growing regions in Bangladesh. A multiresidue method was developed to detect the pesticide levels in the collected samples using gas chromatography with mass spectrophotometry (GC–MS). Pesticide residues were detected in 51.30% of the total samples, and among the positive samples, 38.89% contained levels above the maximum residue levels (MRLs). The most frequently detected pesticides were chlorpyrifos (34) followed by carbofuran (17), diazinon (16), carbaryl (14), malathion (11), endosulfan (8), cypermethrin (7) and dimethoate (6). Some (10.47%) of the samples contained multiple residues. It is concluded that the continuous monitoring and strict regulation of pesticide use on food crops, especially vegetables, are necessary. 相似文献
5.
《Carbon》2015
We present a facile and efficient route to introduce in-plane nanopores on the graphene sheets by activation of graphene aerogel (GA) with phosphoric acid (H3PO4). Results from N2 adsorption and TEM images showed that H3PO4 activation created mesopores with pore size of 2–8 nm on the graphene sheets. With such nanopores on graphene sheets, the activated GA exhibits a specific capacitance of 204 F g−1, enhanced rate capability (69% capacitance retention from 0.2 to 30 A g−1), reduced equivalent series resistance (3.8 mΩ) and shortened time constant (0.73 s) when comparing with the hydrothermally-derived pristine GA and thermally annealed GA in the absent of H3PO4. The excellent capacitive properties demonstrate that introduction of nanopores on GA by H3PO4 activation not only provides large ion-accessible surface area for efficient charge storage, but also promotes the kinetics of electrolyte across the graphene two-dimensional planes. 相似文献
6.
Ling Fan Mingqian Yang Sen Ma Jihong Huang 《International Journal of Food Science & Technology》2022,57(3):1708-1717
This research optimized the extraction and purification of globulin from wheat germ and assessed the molecular weight distribution and structure properties of the globulin obtained. The results showed that the relative extraction efficiency and purity of wheat germ globulin (WGG) reached 18.0% and 89.1% under the enzymolysis conditions of 0.32‰ α-amylase, pH 6.5, and 55 °C. The maximal precipitation rate of WGG (91.3%) was obtained with pH 4.3 (acid precipitation). Additionally, the molecular weight of WGG was mainly distributed below 70 kDa. FT-IR confirmed that random coils (30.95%), β-sheet (27.02%), α-helix (26.55%), and β-turn (15.48%) were the secondary structures of WGG. Furthermore, LTQ mass spectrometry showed that WGG was rich in variety and high in complexity, which retrieved 1274 proteins belonging to 392 proteomes by inverse peptide analysis. The findings endow a great potential of preparing WGG with superior functionality for food applications. 相似文献
7.
8.
Potassium-ion batteries (PIBs) have aroused considerable interest as a promising next-generation advanced large-scale energy storage system due to the abundant potassium resources and high safety. However, the K+ with large ionic radius brings restricted diffusion kinetics and severe volume expansion in electrode materials, resulting in inferior actual rate characteristics and rapid capacity fading. Designing electrode materials with one-dimensional (1D) nanostructure can effectively enhance various electrochemical properties due to the well-guided electron transfer pathways, short ionic diffusion channels and high specific surface areas. In this review, we summarize the recent research progress and achievements of 1D nanostructure electrode materials in PIBs, especially focusing on the development and application of cathode and anode materials. The nanostructure, synthetic methods, electrochemical performances and structure-performance correlation are discussed in detail. The advanced characterizations on the reaction mechanisms of 1D nanostructure electrode materials in PIBs are briefly summarized. Furthermore, the main future research directions of 1D nanostructure electrode materials are also predicted, hoping to accelerate their development into the practical PIBs market. 相似文献
9.
Ke Xu Zhenyun She Hongwei Wang Xingli Liu Yanyan Zhang Chengdeng Chi Hua Zhang 《International Journal of Food Science & Technology》2021,56(8):4081-4090
Effects of germination on components and structural changes of rice flours and, in turn, rheological properties and textural attributes of sweet dumplings were investigated in this study. Germination decreased starch, protein and lipid content, while slightly increased free amino acids content. Starch granular surface corroded, crystalline structure disrupted, and short-range ordered structures and helical structures decreased with germination. Moreover, germination resulted in a decreased paste viscosity and gel intensity of flour and a reduction of hardness and adhesiveness of dumplings. According to the Pearson’s correlation analysis, flours components and starch structures were significantly correlated with flours rheological properties that determined textural attributes of sweet dumplings. The germination contributed to significant changes in flours components and starch structures, which suggested the pretreatment of germination of waxy rice could be a promising pathway to control textural properties of sweet dumplings. 相似文献
10.
《Food Control》2014
This paper studies the ozone treatment effect on degradation of aflatoxin B1 (AFB1) in corn with different moisture content (MC). The toxicity of the degradation products (DPs) of the ozone-treated AFB1-Contaminated Corn (ACC) was also evaluated using the human hepatocellular carcinoma cell line (HepG2) as model cells. The degradation rate of AFB1 in corn increases with ozone concentration and treatment time. The results showed that ACC with 13.47% MC was easier to be degraded by ozone than with 20.37% MC. Treated with 90 mg L−1 ozone for 20 min and 40 min, AFB1 in corn with 13.47% MC decreased from 83 μg kg−1 to 18.12 μg kg−1 and 9.9 μg kg−1, respectively, well meeting the China National Standard of AFB1 in corn (20 μg kg−1). In order to evaluate the safety of ozone used on ACC, the impacts of AFB1 as well as untreated and ozone-treated ACC with the same level of AFB1 content on HepG2's survival rate, morphology, and apoptosis were studied. The results showed that ACC had high cell toxicity while the toxicity of ozone-treated ACC had no significant difference with that of the AFB1-free culture solution. It is concluded that ozonation can quickly and effectively degrade AFB1 in corn and diminish ACC's toxicity, and therefore, ozonation is expected to be an effective, fast, and safe method for AFB1 degradation in ACC. 相似文献