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1.
以黏胶短纤维和再生植物纤维为主要原料,采用短纤维干法成网-针刺加固工艺,在针刺密度为60~160针/cm2、针刺深度为3.5~ 12.0 mm、针刺频率为720~ 940次/min的条件下,制备单位面积质量在196~979g/m2、厚度在3.6~ 14.4 mm、再生植物纤维质量分数在39.6% ~ 70.9%的针刺复合生态土工布,用于植生护坡.性能测试和植物种植试验结果表明:针刺复合生态土工布具有较好的力学性能和吸水保水性能,且对植物的生长具有良好的促进作用;随着针刺复合生态土工布单位面积质量的增加,其力学性能增加,吸水保水性能变好,发芽率、植株高度和植株质量也均呈现出增加的趋势.  相似文献   
2.
The production of macrofungi (mushrooms) as well as their economic value have been steadily increasing globally. The use of functional foods, dietary supplements, and traditional medicines derived from macrofungi is increasing as they have numerous health benefits as well as abundant nutrients. Macrofungi are diverse with complex and highly varied growth conditions and bioactive constituents, most macrofungal resources have not yet been fully explored and applicated, leading to an urgent need for appropriate strategies to address the problem. Increasing attention has been paid to the macrofungal cultivation and application, in particular, potential prebiotics. Herein, the present review comprehensively summarizes recent progress in the cultivation, newly identified bioactive constituents, and their effects on gut microbiota as well as the potential ways in which they affect human health. Moreover, the macrofungal food development is discussed to improve food nutritional value and change the quality characteristics of food. Finally, the review addresses consumer safety concerns and the prospective genetic manipulation of macrofungi. We hope that this review can provide a comprehensive research reference for ensuring the safety and efficacy, along with maximizing the value and profitability of macrofungi production.  相似文献   
3.
以伊犁矿区第三系砂砾岩含水层下综放开采为工程背景,利用相似模拟实验研究了采动引起覆岩的破断特征。结果表明,工作面推进到135 m左右,裂隙带即与砂砾岩含水层贯通,这对于6-7煤层安全高效开采造成较大威胁。为了保障工作面回采安全,设计了超前探放水钻孔,累计泄水量344 800 m3,大幅度减少了对粗砂岩流砂层的补给作用;对首采综放工作面现场观测表明,垮落到采空区的粗砂岩流砂层成为湿润的固体砂,固体砂覆盖于采空区又起到防灭火的作用,对矿井安全生产十分有利。  相似文献   
4.
Electroslag casting(ESC)is an important method to produce high quality castings.In this study,the ESC up-pulling inner mold method(EUPIM)was used to produce hollow cylindrical castings with the multiple consumable electrodes.The radial deformation,the axial and radial internal stress of the inner mold,and the axial internal stress of the slag shell were analyzed using the finite element method(FEM)with the aid of ANSYS software.The ProCAST software was used to calculate the specific heat,heat conductivity and density curve of Cu.Simulation results show that the radial deformation,the axial and radial internal stress of the inner mold,and the axial internal stress of the slag shell near the slag-metal interface of hollow cylndrical casting gradually increase from 0 s to 360 s after the ESC starting(slagging)process but before applying the up-pulling force.The suitable initial up-pulling moment of the inner mold is at around 180-198 s after the starting process.  相似文献   
5.
Structural and Multidisciplinary Optimization - Circumferentially grooved seals have been widely used in pumps to eliminate outward leakage of rotating liquid. On many occasions, the turbulent flow...  相似文献   
6.
As a decisive attribute, flavour could be influenced by HP treatments through multiple physical and chemical pathways within the high pressure (HP)-assisted meat curing process. This investigation aimed to identify the major pathway influencing volatile flavour patterns of two representative vinasse-cured duck (VCD) products with HP treatments (150–300 MPa/15 min), including wet and dry types, by employing headspace fingerprinting as an untargeted approach. Results suggested that HP treatments greatly lowered moisture contents and increased Warner-Bratzler shear force and thiobarbituric acid reactive substances of the cured samples. According to multivariate models, the volatile flavour patterns of the HP-processed VCD could be clearly separated from the unprocessed samples, but the VCD pressurised at different intensities represented similar volatile fingerprinting, which was validated by e-nose analysis. The discriminant analysis (OPLS-DA) model outlined vinasse-derived ethanol, acetic acid, 3-methyl-1-butanol, 2-methyl-1-butanol, phenethyl alcohol and 2-methyl-3-octanone as the major discriminant aromas across the unpressurised and pressurised samples.  相似文献   
7.
The hydrocarbon production in the Bawu area of Lishu Depression is high. However, the Bawu area has undergone three main tectonic movements, the strata were strongly uplifted and eroded, and the fractures were extremely developed. The conditions of hydrocarbon preservation have become intricate. In this study, by analyzing isotopes compositions and geochemical features of formation water, and the characteristics of formation pressure, the hydrocarbon preservation can be deduced. The subnormal and lower normal pressure zones (away from Xiaokuan Fault) of Yingcheng and Shahezi Formations are relatively closed and more conducive to hydrocarbon preservation.  相似文献   
8.
氨基甲酸乙酯(EC)是发酵食品(面包、酸奶、大豆奶酪等)和酒精饮料(葡萄酒、清酒、黄酒等)在发酵过程中,含氮化合物不完全代谢产生的副产物,与乙醇自发反应产生的,对人体具有潜在遗传毒性和致癌性。黄酒是我国传统而独特的发酵酒,因独特的风味和较高的营养价值,而深受消费者的喜爱。然而,在传统黄酒中,氨基甲酸乙酯含量显著高于其它酒精饮料,对消费者健康构成潜在的安全隐患。降低黄酒中氨基甲酸乙酯含量对黄酒产业的可持续发展具有重要意义。本文综述尿素、瓜氨酸及精氨酸分别在酿酒酵母及乳酸菌细胞中代谢调控机制,以及黄酒酿造过程中EC消减的方法。  相似文献   
9.
目前,在加气混凝土行业中有很多的企业都在寻求扩大生产规模,以自动化、规模化生产寻求发展。目前行业中企业最大规模达200多万m3/a,近年来新上生产线行业平均规模25万m3/a以上,年生产规模50万m3的企业数明显增加。在原有生产线基础上改扩建年产40万m3加气混凝土砌块及板材生产线已成为加气混凝土企业的普遍现象,这样的项目建设既可使电厂排放的粉煤灰及脱硫石膏等资源得到充分利用,又可以缓解周边新型墙材市场供求紧张局面,且兼顾适应未来装配式建筑构件的发展,同时还可以改善当地环境状况,取得较好的企业经济效益。  相似文献   
10.
Infrared (IR) photodetectors are a key optoelectronic device and have thus attracted considerable research attention in recent years. Photosensitivity is an increasingly important device performance parameter for nanoscale photodetectors and image sensors, as it determines the ultimate imaging quality and contrast. However, photosensitivities of state-of-the-art low-dimensional nanostructure-based IR detectors are considerably low, limiting their practical applications. Herein, a biomimetic IR detection amplification (IRDA) system that boosts photosensitivity by several orders of magnitude by introducting nanowire field effect transistors (FETs), resulting in a peak photosensitivity of 7.6 × 104 under an illumination of 1342 nm, is presented. Consequently, high-contrast imaging of IR light is obtained on the flexible IRDA arrays. The image information can be then trained and recognized by an artificial neural network for higher image-recognition efficiency. This work provides a new perspective for developing high-performance IR imaging systems, and is expected to undoubtedly enlighten future work on artificial intelligence and biorobotic systems.  相似文献   
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