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101.
花生粕是重要的蛋白饲料原料,但由于其氨基酸不平衡,特别是精氨酸与赖氨酸比例严重失衡(精氨酸与赖氨酸含量比值在3~4,理想的精氨酸与赖氨酸含量比值为1.0),限制了其在动物养殖中的应用。研究了复合酶预处理结合乳酸菌发酵花生粕对其品质的改善。结果表明:经菌酶协同处理后,花生粕粗蛋白质含量由46.4%提高至506%,大分子蛋白明显降解为小分子蛋白,酸溶蛋白质含量由2.3%提高至17.8%,多肽含量由1.6%提高至15.7%,蛋氨酸和赖氨酸含量分别提高了77.1%和42.0%,精氨酸降解率为18.7%,精氨酸与赖氨酸含量比值从3.7降低至2.1,总酸含量由06%提高到4.7%,其中乳酸含量由0.64 mg/g提高至14.63 mg/g。菌酶协同处理后的花生粕抗氧化性明显增强,其中每克菌酶协同处理后的花生粕对羟自由基的清除能力与171.6 mg VC相当,比花生粕(与47.6 mg VC相当)提高了2.6倍。 相似文献
102.
针对云计算应用于无线传感器网络(Wireless Sensor Network,WSN)时延敏感型业务时存在的高传输时延问题,提出了一种WSN低功耗低时延路径式协同计算方法。该方法基于一种云雾网络架构开展研究,该架构利用汇聚节点组成雾计算层;在数据传输过程中基于雾计算层的计算能力分步骤完成任务计算,降低任务处理时延;由于汇聚节点计算能力较弱,时延降低将导致能耗增加,WSN工作寿命减短,为此提出能耗约束下的任务映射策略,并利用离散二进制粒子群优化(Binary Particle Swarm Optimization,BPSO)算法解决能耗约束下的时延优化问题。仿真结果表明,在相同的能耗约束下,对比其他算法,基于BPSO算法得出的映射方案能有效降低业务处理时延,满足时延敏感型业务的需求。 相似文献
103.
104.
《Ceramics International》2022,48(22):32827-32836
To investigate the crystal structure, electrical properties, and magnetic properties of Ca–Sn co-doped Y3-xCaxFe5-xSnxO12 (x = 0.00–0.25 in steps of 0.05), solid-state reaction experiments, first principles calculations, and complex crystal bonding theoretical calculations were performed. The relative permittivity (εr) is strongly correlated with the average bond ionicity when Ca2+ is added. Furthermore, appropriate Sn4+ substitution significantly lowers the dielectric loss (tanδε) associated with the lattice energy. The right amount of Ca–Sn co-doping can change the saturation magnetization (4πMS) and improve the microscopic morphology of YIG, lowering the ferromagnetic resonance linewidth (ΔH) of YIG. The optimized microwave dielectric and magnetic properties are as follows: εr = 14.7, tanδε = 4.15 × 10?4, 4πMS = 1680 G, and ΔH = 53 Oe for Y2.8Ca0.2Fe4.8Sn0.2O12 sintered for 6 h at 1425 °C. Based on this material, a simple 3D model of a strip-line circulator with an insertion loss of less than 0.3 dB at each port and isolation greater than 20 dB in the 10–12 GHz range was developed, indicating the potential of the material for microwave high-frequency components such as circulators. 相似文献
105.
106.
目的 了解公众对网络食品药品谣言信息及虚假宣传甄别能力和行为态度,探索防范谣言传播、维护社会稳定的有效措施和途径。方法 采用随机抽样研究方法,对贵州省某少数民族自治州公众开展食品药品网络谣言及虚假宣传辨识能力、行为态度问卷调查。结果 当地公众食品药品网络谣言及虚假宣传辨识能力总体较低,经济发展落后地区的青少年人群对网络谣言及虚假宣传的辨识能力较弱。大部分公众处理网络食品药品安全信息较为理性,更愿意通过国家监管部门权威网站了解信息,基本具备了确认信息真实性的主观意识,但辟除谣言的行动能力不高。结论 地方党委政府及有关部门应加强食品药品网络谣言和虚假宣传治理,加大当地谣言及虚假宣传的监测和系统性分析研究,有针对性、预判性地进行治理和科普宣传。 相似文献
107.
As the formaldehyde is one of the main indoor pollutants, the purpose of this study is to effectively remove indoor formaldehyde pollution by using environmentally friendly 3D printing ornaments. The wood 3D printing filaments cellulose/polylactic acid composite (Cellu/P) was selected as the starting material, and 3-aminopropyltriethoxysilane (APTES) was used for chemical modification to obtain a series of cellulose composite materials with amino groups. The modified composite materials (APTES@Cellu/P) were characterized by Fourier transform infrared, X-ray diffraction, scanning electron microscope, energy dispersive spectroscopy, thermogravimetric analysis, and mechanical tests, and a formaldehyde removal experiment was performed. The feasibility of 3D printing was evaluated, and the process of 3D printing-functionalized customized ornaments was proposed, and then a school emblem was used for modeling, printing, and surface modification. Compared with the commercially traditional activated carbon, 3D printing-customized ornaments of APTES@Cellu/P material has a better formaldehyde removal effect, and can even avoid the secondary pollution that is common to the activated carbon. 相似文献
108.
Jianrong Xia Hanyu Xue Renjin Gao Yuchi Zhang Qi Lin 《Polymer Engineering and Science》2021,61(2):489-496
The over-exploitation of finite fossil resources and/or the increased environmental and sustainable awareness inspire scientists and technologists to search for inexpensive alternatives from renewable chemicals. Phenol formaldehyde (PF) resins, the oldest type of synthetic polymers with good mechanical properties and heat resistance, are widely used in the production of coatings, laminates, molding compositions, and glues. Here, biobased urushiol-derived PF resins were synthesized from the alkali-catalyzed reaction between urushiol and formaldehyde. The chemical compositions and molecular structures of resole resins were characterized by carbon-13 nuclear magnetic resonance and Fourier transform infrared spectroscopy, and their curing behaviors were studied by differential scanning calorimetry. The as-prepared urushiol-derived resole resins had methylol (Ph−CH2OH), ortho- and para-hemiformal groups (Ph−CH2OCH2OH), and the para−para/ortho−para/ortho−ortho links of methylene groups (Ph−CH2−Ph), whereas the resole resins had low curing temperatures at about 100–113°C. Additionally, given the long side alkyl group moiety on the aromatic rings of urushiol, the films of cured urushiol-derived resole resins had low glass transition temperatures of 132 ± 2°C. Furthermore, the as-prepared urushiol-derived coatings exhibited excellent physical and mechanical properties. 相似文献
109.
110.
In this article, we have studied the effect of carbonaceous nanofillers viz. fullerenol (0D), carboxylated multi-wall carbon nanotube (MWCNT, 1D), hydroxylated graphene (2D) and combination of carboxylated CNT and hydroxylated graphene as 3D in thermoplastic polyurethane on the tensile properties of the fabricated cellular structures. The concentration of nano-fillers was varied as 0.1, 1, and 5 wt%. Tensile properties of the nanocomposite cellular structures were measured as per ASTM D882 at 20°C (below glass transition temperature, Tg) and 40°C (above Tg). The results have shown that the tensile strength was found to increase by 200%–300% and the tensile modulus was found to increase by 150%–300% for 2D and 3D nano-fillers while significantly poor results were observed for 0D. However, the test data tensile strength and modulus showed marginal increase at 20°C and marginally low at 40°C for 1D filler. The interfacial adhesion was calculated by using experimental tensile data and the predictive models. The interfacial adhesion parameter (Bσ) calculated using Pukanszky equation was found significantly higher value for 2D (Bσ20 = 195.8) and 3D (Bσ20 = 192.0) fillers while poor adhesion was observed for 0D (Bσ20 = −81.6) fillers. The developed cellular structured materials were also evaluated by attenuated total reflection Fourier transform IR spectra, differential scanning calorimetry, X-ray diffraction, scanning electron microscope, and transmission electron microscope. 相似文献