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1.
Soybean oil hydrogenation alters the linolenic acid molecule to prevent the oil from becoming rancid, however, health reports have indicated trans-fat caused by hydrogenation, is not generally regarded as safe. Typical soybeans contain approximately 80 g kg−1 to 120 g kg−1 linolenic acid and 240 g kg−1 of oleic acid. In an effort to accommodate the need for high-quality oil, the United Soybean Board introduced an industry standard for a high oleic acid greater than 750 g kg−1 and linolenic acid less than 30 g kg−1 oil. By combing mutations in the soybean plant at four loci, FAD2-1A and FAD2-1B, oleate desaturase genes and FAD3A and FAD3C, linoleate desaturase genes, and seed oil will not require hydrogenation to prevent oxidation and produce high-quality oil. In 2017 and 2018, a study comparing four near-isogenic lines across multiple Tennessee locations was performed to identify agronomic traits associated with mutations in FAD3A and FAD3C loci, while holding FAD2-1A and FAD2-1B constant in the mutant (high oleic) state. Soybean lines were assessed for yield and oil quality based on mutations at FAD2-1 and FAD3 loci. Variations of wild-type and mutant genotypes were compared at FAD3A and FAD3C loci. Analysis using a generalized linear mixed model in SAS 9.4, indicated no yield drag or other negative agronomic traits associated with the high oleic and low linolenic acid genotype. All four mutations of fad2-1A, fad2-1B, fad3A, and fad3C were determined as necessary to produce a soybean with the new industry standard (>750 g kg−1 oleic and <30 g kg−1 linolenic acid) in a maturity group-IV-Late cultivar for Tennessee growers.  相似文献   
2.
Recently, single image super-resolution (SISR) has been widely applied in the fields of underwater robot vision and obtained remarkable performance. However, most current methods generally suffered from the problem of a heavy burden on computational resources with large model sizes, which limited their real-world underwater robotic applications. In this paper, we introduce and tackle the super resolution (SR) problem for underwater robot vision and provide an efficient solution for near real-time applications. We present a novel lightweight multi-stage information distillation network, named MSIDN, for better balancing performance against applicability, which aggregates the local distilled features from different stages for more powerful feature representation. Moreover, a novel recursive residual feature distillation (RRFD) module is constructed to progressively extract useful features with a modest number of parameters in each stage. We also propose a channel interaction & distillation (CI&D) module that employs channel split operation on the preceding features to produce two-part features and utilizes the inter channel-wise interaction information between them to generate the distilled features, which can effectively extract the useful information of current stage without extra parameters. Besides, we present USR-2K dataset, a collection of over 1.6K samples for large-scale underwater image SR training, and a testset with an additional 400 samples for benchmark evaluation. Extensive experiments on several standard benchmark datasets show that the proposed MSIDN can provide state-of-the-art or even better performance in both quantitative and qualitative measurements.  相似文献   
3.
光动力疗法(PDT)以其超高时空分辨率、非侵入性及低毒副作用的优点,被认为是治疗癌症和各种非恶性疾病的有效疗法之一。本文主要综述了几类光敏剂发展历史、主要结构、特点及研究进展,分析了高性能光敏剂的开发动态,包括化学修饰;与具有特定细胞受体的其他配体缀合成复合光敏剂;采取纳米技术,如纳米颗粒输送,基于富勒烯的光敏剂等。基于此,指出具有临床应用前景的高性能光敏剂的基本特征、设计原则及发展趋势。  相似文献   
4.
This paper focuses on the design of a 2.3–21 GHz Distributed Low Noise Amplifier (LNA) with low noise figure (NF), high gain (S21), and high linearity (IIP3) for broadband applications. This distributed amplifier (DA) includes S/C/X/Ku/K-band, which makes it very suitable for heterodyne receivers. The proposed DA uses a 0.18 μm GaAs pHEMT process (OMMIC ED02AH) in cascade architecture with lines adaptation and equalization of phase velocity techniques, to absorb their parasitic capacitances into the gate and drain transmission lines in order to achieve wide bandwidth and to enhance gain and linearity. The proposed broadband DA achieved an excellent gain in the flatness of 13.5 ± 0.2 dB, a low noise figure of 3.44 ± 1.12 dB, and a small group delay variation of ±19.721 ps over the range of 2.3–21 GHz. The input and output reflection coefficients S11 and S22 are less than −10 dB. The input compression point (P1dB) and input third-order intercept point (IIP3) are −1.5 dBm and 11.5 dBm, respectively at 13 GHz. The dissipated power is 282 mW and the core layout size is 2.2 × 0.8 mm2.  相似文献   
5.
文曼  熊春荣 《精细化工》2021,38(5):981-987
采用溶胶-凝胶法制备CuO-SiO2复合气凝胶,通过在气凝胶孔道内填充TiCl4,然后将其气相水解,得到了在CuO-SiO2气凝胶表面生长了高结晶度的TiO2纳米纤维(CuO-SiO2@TiO2),纤维直径~16 nm.通过XPS、UPS、UV-Vis DRS、荧光光谱(PL)等表征了材料的结构及光电性能.结果表明,制备的CuO-SiO2@TiO2对可见光有明显吸收,且荧光强度较商用TiO2(P25)大幅降低,光生电子-空穴对更加稳定.再在纳米纤维上负载CuO,所得CuO-SiO2@TiO2/CuO在可见光区的荧光强度进一步增强.以300 W氙灯为光源,分别以CuO-SiO2@TiO2及CuO-SiO2@TiO2/CuO为催化剂,无牺牲剂条件下光催化还原CO2,4 h后甲醇产率分别为1304.0及1589.0μmol/g-cat,转换频率(TOF)分别为0.038及0.046 h–1.循环实验表明,纳米纤维具有较好的光催化稳定性,经过4次光催化循环实验后,CuO-SiO2@TiO2/CuO的保留率~94%,甲醇产率可达1472.0μmol/g-cat,TOF为0.042 h–1.  相似文献   
6.
A series of tetrathiophene-based fully non-fused ring acceptors (4T-1, 4T-2, 4T-3, and 4T-4), which can be paired with the star donor polymer PBDB-T to fabricate highly efficient organic solar cells are developed. Tailoring the size of lateral chains can tune the solubility and packing mode of acceptor molecules in neat and blend films. It is found that the incorporation of 2-ethylhexyl chains can effectively change the compatibility with the donor polymer PBDB-T, and an encouraging power conversion efficiency of 10.15% is accomplished by 4T-3-based organic solar cells. It also presents good compatibility with the other polymer donor and an even higher power conversion efficiency (PCE) of 12.04% is achieved based on D18:4T-3 blend, which is the champion PCE for the fully non-fused acceptors. Importantly, these inexpensive tetrathiophene fully non-fused ring acceptors provide cost-effective photovoltaic performance. The results demonstrate a high photovoltaic performance from synthetically inexpensive materials could be achieved by the rational design of non-fused ring acceptor molecules.  相似文献   
7.
Images with hazy scene suffer from low-contrast, which reduces the visible quality of the scene, thus making object detection a more challenging task. Low-contrast can result from foggy weather conditions during image acquisition. Dehazing is a process of removal of haze from the photography of a hazy scene. Single-image dehazing based on dark channel priors are well-known techniques in this field. However, the performance of such techniques is limited to priors or constraints. Moreover, this type of method fails when images have sky-region. So, a method is proposed, which can restore the visibility of hazy images. First, a hazy image is divided into blocks of size 32 × 32, then the score of each block is calculated to select a block having the highest score. Atmospheric light is calculated from the selected block. A new color channel is considered to remove atmospheric scattering, obtained channel value and atmospheric light are then used to calculate the transmission map in the second step. Third, radiance is computed using a transmission map and atmospheric light. The illumination scaling factor is adopted to enhance the quality of a dehazed image in the final step. Experiments are performed on six datasets namely, I-HAZE, O-HAZE, BSDS500, FRIDA, RESIDE dataset and natural images from Google. The proposed method is compared against 11 state-of-the-art methods. The performance is analyzed using fourteen quantitative evaluation metrics. All the results demonstrate that the proposed method outperforms 11 state-of-the-art methods in most of the cases.  相似文献   
8.
为探究某加氢装置高压换热器管束腐蚀泄漏原因,利用Aspen Plus工艺模拟软件计算了冷低压分离器油相(简称冷低分油)中水质量分数分别为1%,2%,3%时,冷低分油系统的露点温度、氯化铵结晶温度、氯化铵潮解点温度和相对湿度。结果表明:相较于经验的露点温度预测方法,通过引入潮解点、划分系统“湿环境”温度范围判断氯化铵垢下腐蚀风险区域的方法与实际腐蚀案例更为切合;在3种油相含水条件下,换热器管束存在氯化铵垢下腐蚀的“湿环境”温度范围分别为:50~103 ℃,50~161 ℃,50~176 ℃;随着油相中含水量的提高,“湿环境”腐蚀区域逐渐向高温部位迁移,预计铵盐导致的垢下腐蚀将会愈加严重。  相似文献   
9.
Gecko-inspired microfibrillar adhesives have achieved great progress in microstructure design and adhesion improvement over the past two decades. Space applications nowadays show great interest in this material for the characteristics of reversible adhesion and universal van der Waals interactions. However, the impact of harsh environment of space on the performance of microfibrillar adhesives, especially the extreme low temperature, is rarely addressed. Herein, microfibrillar adhesives fabricated by phenyl containing polydimethylsiloxane (p-PDMS) elastomers with superior low-temperature reversible adhesion is proposed. p-PDMS elastomers are synthesized through one-pot anionic ring-opening copolymerization, and the resulting elastomers become non-crystallizable with excellent low-temperature elasticity. Low-temperature adhesion tests demonstrate that the adhesion strength of microfibrillar adhesives fabricated by p-PDMS elastomers can be well maintained to as low as −120 °C. In contrast, the adhesion strength of pure PDMS microfibrillar adhesive reduces more than 50% below its crystallization temperature. The low-temperature cyclic adhesion tests further demonstrate that p-PDMS microfibrillar adhesives exhibit superior reversible adhesion compared to that of PDMS microfibrillar adhesives, owing to the sustainable conformal contact and even distribution of loads over repeated cycles. This study provides a new fabrication strategy for microfibrillar adhesives, and is beneficial for the practical application of microfibrillar adhesives.  相似文献   
10.
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