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31.
32.
Renata Quartieri Nascimento Cludio Vaz Di Mambro Ribeiro Nelson Barros Colauto Larissa da Silva Paulo Vitor Frana Lemos Ederlan de Souza Ferreira Giani Andrea Linde Bruna Aparecida Souza Machado Pedro Paulo Lordelo Guimares Tavares Aline Camaro Telles Biasoto Marcelo Andres Umsza Guez Natlia Carvalho Denílson de Jesus Assis Jania Betnia Alves da Silva Carolina Oliveira de Souza 《Molecules (Basel, Switzerland)》2022,27(20)
Edible insects are a potential alternative food source of high feed conversion efficiency and protein content. Zophobas atratus is an edible insect that adapts to different diets, enabling sustainable rearing by adding value to by-products and agro-industrial residues. This study aimed to evaluate the performance and nutritional characterization of Zophobas atratus larvae fed with different proportions of grape residue. Physicochemical analysis of the diets and larvae (AOAC procedures), fatty acid profile (chromatographic techniques), metals and non-metals (inductively coupled plasma optical emission spectrometry), larval mass gain, feed conversion efficiency, and mortality rate were assessed. The replacement of 25% of the conventional diet with grape residue increased lipid, ash, and fiber contents and reduced protein, carbohydrates, and energy. It promoted greater mass gain, lower mortality rate, and reduced larval growth time by 51%. Among the replacements, 25% resulted in the second-highest content of calcium, sodium, magnesium, and zinc, and the lowest content of potassium and phosphorus in the larvae. The 100% replacement resulted in the highest amounts of C18:2n6 (27.8%), C18:3n3 (2.2%), and PUFA (30.0%). Replacing 25% of the conventional diet with grape residue is equivalent to the conventional diet in many aspects and improves several larvae performance indices and nutritional values. 相似文献
33.
This work was focused on the rust conversion of proanthocyanidins (PC) for goethite (α-FeOOH), akaganeite (β-FeOOH) and lepidocrocite (γ-FeOOH), trying to show the potential of PC as an eco-friendly corrosion inhibitor and rust converter for archaeological steel conservation. The experiment used a rusted steel screw from Lingzhao Xuan of the Forbidden City in the Qing Dynasty and three kinds of pure iron oxyhydroxides as research samples. By means of micro-Raman, FTIR, XRD, XPS, SEM and EIS, PC had the ability to chemically react with iron oxyhydroxides in the rust, forming amorphous PC-FeOOH with a marked signal about 1384 cm−1 as phenolic-Fe in infrared properties. The original relatively stable iron oxides were not induced to phase transformation and still remained. The converted rust layer could be more stable in the corrosive medium and increased the corrosion potential more effectively. Both the rust layer resistance and the charge transfer resistance of the archaeological samples were improved by at least 3 times with 5.0 g/L of PC, which could reasonably stabilize the archaeological rust and hindered external corrosive penetration into the core. It was a mild protection material that showed satisfactory performance for archaeological steel cultural heritage and has a good application prospect. 相似文献
34.
一种全光归零码到非归零码变换的新技术方案 总被引:2,自引:0,他引:2
报道了一种利用单只半导体光放大器和光滤波器实现全光归零码到非归零码变换的新技术方案.当探测(Probe)光和数据信号光同时输入到SOA时,基于SOA中的交叉增益调制和交叉相位调制现象,探测光光谱的后沿和前沿将分别产生红移和蓝移.通过调节光滤波器和探测光的中心波长之间的失调量,滤出光谱的特定部分,可以得到转换后的NRZ码光信号.这种新型的全光码型变换器具有结构简单、偏振不敏感、控制参量少和稳定性高的特点.分别采用仿真和实验的方式实现了20 Gbit/s光数据信号从RZ码到NRZ码的全光码型变换,并且仿真结果和实验结果相吻合. 相似文献
35.
有序介孔材料是指孔径在2~50 nm之间的多孔材料, 是一类具有均匀孔径、 高有序度纳米孔道和高比表面积的新材料. 在过去30年里, 有序介孔材料的研究取得了长足的进步, 在可控合成、 结构设计和调控及功能化等方面形成了系统的理论. 同时, 其应用领域也不断被拓展, 包括能源存储与转化、 催化、 生物医药和传感等方面. 本文首先回顾了有序介孔材料的发展历史, 简要介绍发展过程中“里程碑式”的研究工作; 然后根据构效关系总结了其在不同领域应用的最新进展; 最后讨论了有序介孔材料领域进一步发展所面临的挑战与机遇, 并对未来前景进行了展望. 相似文献
36.
通过环境友好的葡萄糖模板法和改进的湿化学还原法制备了聚二甲基硅氧烷/铜纳米线(PDMS/CuNWs)复合薄膜, 其采用的“类夹心结构”有效解决了铜在空气中易氧化进而导致电导率大幅度下降的问题, 同时获得了具有优异电磁屏蔽和光热转化性能的双功能轻质柔性复合薄膜. CuNWs面密度为1.6 g/cm2的复合薄膜在重复弯折1000次后性能保持率最高可达99.07%; CuNWs面密度为2.4 g/cm2的复合薄膜在X波段下总电磁屏蔽效能达到30.1 dB, 屏蔽效率达到99.9%; 同时, 在2 W/cm2的近红外光照射下, 复合薄膜在仅加热15 s后其表面温度高达211.2 ℃, 具有十分快速的光热响应和转化效率. 相似文献
37.
作为一种洁净能源,硅锗合金的热电转换性能的研究越来越受到人们的重视.本文重点研究了不同Ge浓度的硅锗合金以及Si、Ge单晶在300~1100K温度范围内,Seebeck系数随温度的变化.并对组分相同导电类型不同、晶向不同以及结晶状态不同的样品的Seebeck系数进行了比较.在研究温度区间,Seebeck系数的绝对值大小一般在200~600μV/K之间,随温度不同连续变化.通过对比发现SiGe合金的Seebeck系数大小不仅与Ge的浓度和温度有关,其他因素对其绝对值也有影响,其中晶向最为明显,表现出了明显的各向异性.此外,材料本身的电阻率除了作为一个热电参数影响最优值外,其大小还对Seebeck系数的绝对值有影响,即掺杂济浓度对Seebeck系数的影响. 相似文献
38.
Natural cellulose substances have been proven to be ideal structural templates and scaffolds for the fabrication of artificial functional materials with designed structures, psychochemical properties and functionalities. They possess unique hierarchically porous network structures with flexible, biocompatible, and environmental characteristics, exhibiting great potentials in the preparation of energy-related materials. This minireview summarizes natural cellulose-based materials that are used in batteries, supercapacitors, photocatalytic hydrogen generation, photoelectrochemical cells, and solar cells. When natural cellulose substances are employed as the structural template or carbon sources of energy materials, the three-dimensional porous interwoven structures are perfectly replicated, leading to the enhanced performances of the resultant materials. Benefiting from the mechanical strengths of natural cellulose substances, wearable, portable, free-standing, and flexible materials for energy storage and conversion are easily obtained by using natural cellulose substances as the substrates. 相似文献
39.
Xianquan Liao Yuxin Liu Qi Jia Prof. Jing Zhou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(43):11094-11101
Solar-driven photothermal antibacterial devices have attracted a lot of interest due to the fact that solar energy is one of the cleanest sources of energy in the world. However, conventional materials have a narrow absorbance band, resulting in deficient solar harvesting. In addition, lack of knowledge on temperature change in these devices during the photothermal process has also led to a waste of energy. Here, we presented an elegant multi-channel optical device with a multilayer structure to simultaneously address the above-mentioned issues in solar-driven antibacterial devices. In the photothermal channel, semiconductor IrO2-nanoaggregates exhibited higher solar absorbance and photothermal conversion efficiency compared with nanoparticles. In the luminescence channel, thermal-sensitive Er-doped upconversion nanoparticles were utilized to reflect the microscale temperature in real-time. The bacteria were successfully inactivated during the photothermal effect under solar irradiation with temperature monitoring. This study could provide valuable insight for the development of smart photothermal devices for solar-driven photothermal bacterial inactivation in the future. 相似文献
40.
Laxmi Narayan Tripathi Sourabh Barua 《Progress in Crystal Growth and Characterization of Materials》2019,65(4):100465
This review article covers the growth and characterization of two-dimensional (2D) crystals of transition metal chalcogenides, h-BN, graphene, etc. The chemical vapor transport method for bulk single crystal growth is discussed in detail. Top-down methods like mechanical and liquid exfoliation and bottom-up methods like chemical vapor deposition and molecular beam epitaxy for mono/few-layer growth are described. The optimal characterization techniques such as optical, atomic force, scanning electron, and Raman spectroscopy for identification of mono/few-layer(s) of the 2D crystals are discussed. In addition, a survey was done for the application of 2D crystals for both creation and deterministic transfer of single-photon sources and photovoltaic systems. Finally, the application of plasmonic nanoantenna was proposed for enhanced solar-to-electrical energy conversion and faster/brighter quantum communication devices. 相似文献