Monolayer MoS2 Dendrites on a Symmetry‐Disparate SrTiO3 (001) Substrate: Formation Mechanism and Interface Interaction

Dendritic patterns generated in non‐equilibrium growth processes are prevalent in nature while their formation mechanisms are far from fully understood. Here, we report a coverage‐dependent fractal degree evolution of monolayer 2H‐MoS₂ dendrites synthesized on a symmetry‐disparate substrate of SrTiO₃ (001). Surprisingly, various characterizations have revealed that the monolayer dendrites featured with orthogonal backbones are single crystalline, possessing both peculiar adlayer‐substrate interaction and abnormal indirect bandgap on SrTiO₃ (001). Further theoretical calculations indicate that a prominent diffusion anisotropy of monomer precursors, combined with the disparate adlayer‐substrate symmetry, determine the diffusion‐limited aggregation of MoS₂ towards dendritic shapes. This work provides brand‐new insights in the morphological engineering of two‐dimensional atomic crystals, and contributes greatly to an in‐depth understanding of the detailed dynamics in non‐equilibrium crystal growth.     

Electrical and photovoltaic response of bulk hetero-junction device made from poly (3-phenyl azo methine thiophene) (PPAT) and 1, 1′-diallyl substituted 4, 4′-dipyridine (DADP)

Electrical and photovoltaic properties of donor–acceptor composite system comprised of poly (3-phenyl azo methine thiophene) (PPAT) and 1, 1′–diallyl substituted 4, 4′-dipyridine (DADP) were investigated. A significant enhancement of photocurrent was observed when PPAT was blended with DADP. The increase in photocurrent has been explained in terms of efficient charge separation that resulted from the transfer of photo-excited electrons from PPAT to DADP. The strong quenching of fluorescence of PPAT was caused by the presence of DADP that indicates the photo-induced charge transfer from PPAT to DADP. The open circuit voltage (V_oc) generated in the device is independent of the variation of work function of negative metal electrode that has been explained in terms of Fermi level pinning between DADP and metal via surface charges. The electrical characteristics of ITO/PPAT: DADP/Al photovoltaic device were determined by analyzing the dependence of short circuit photocurrent density (J_sc) and V_oc under illumination at different temperatures. The V_oc decreases almost linearly with increasing temperature, while short-circuit photocurrent increases logarithmically with temperature and saturates at higher temperature above 330 K. This dependence of J_sc and V_oc on temperature has been discussed in terms of possible mechanism that involves the photovoltage generation and charge carrier transport in the device under thermally activated state. The photovoltaic device made from PPAT: DADP blend has shown three times higher photosensitivity than that of made from pure PPAT.     

间断式酸洗磷化生产线研制

常规酸洗磷化生产线不能满足企业生产要求,设计了能循环自动生产的间断式酸洗磷化生产线。该生产线主要由机械部分和电气部分组成。机械部分由大车、盘条准备架、运行小车、工艺槽、工艺轨道、盘条下落架、滑触片等组成。说明各组成部分的功能及控制原理。电气部分包含主控柜和小车控制柜,给出电气系统控制原理图。间断式酸洗磷化生产线采用2条间断式运行轨道,解决了一般生产线占地大的问题,整体通过无线电通信,全程自动生产,节约成本。     

酶解程度对花生蛋白理化性质及功能特性的影响

研究了不同酶解程度对花生蛋白理化性质(包括分子质量、表面疏水性、巯基含量)及功能特性(溶解性、乳化性、抗氧化性)的影响。研究发现:花生蛋白进行不同酶解处理后,分子质量变小、表面疏水性变小、总巯基及暴露巯基呈现先减小后增大的趋势,同时酶解物的功能性质也发生了较大改变,如所有酶解物的溶解性提高,水解产物的乳化稳定性降低,DH5的乳化活性较PPI强,深度水解后DH10、DH15的乳化活性较PPI均明显下降,多酚含量跟DPPH自由基清除率正相关。研究结果为花生蛋白的改性提供了一定的数据支持。     

胶原蛋白涂覆棉纤维的研究

胶原蛋白具有独特的3股螺旋结构,优越的生物相容性和生物降解性,极具应用前景。为了进一步拓展纤维素的应用领域和开发新型绿色纤维素纤维,采用高碘酸钠对棉纤维进行局部有限选择性氧化,然后与胶原蛋白溶液反应,制备了涂覆胶原蛋白棉纤维。结果表明:经高碘酸钠有限氧化后棉纤维的断裂强度降低不明显;胶原蛋白分子通过席夫碱C N双键共价结合在棉纤维表面。     

核桃蛋白有限酶解增溶改性的工艺研究

为充分利用核桃榨油后的核桃粕,研究了核桃蛋白有限酶解增溶改性的工艺,以拓宽核桃蛋白在食品工业中的应用范围,提高产品附加值。通过比较不同蛋白酶对核桃蛋白的水解度和氮溶指数的影响,筛选出胰蛋白酶为最佳用酶。在单因素试验基础上,通过二次回归正交旋转组合试验对胰蛋白酶有限酶解核桃蛋白的工艺加以优化。结果表明,最佳酶解工艺条件为:液料比10∶1,酶解温度43℃,酶解时间52 min,酶用量0.4%。最佳条件下制备的改性核桃蛋白的水解度仅为3.25%,而氮溶指数从8.74%显著提升到78.16%。     

加捻对精纺羊绒纱线的影响分析

如何充分利用纱线的捻系数、捻向等参数来配置精纺羊绒制品的纺纱参数,直接关系到羊绒制品的最终手感和外观风格。从羊绒纱线的捻度和捻向配置出发,对羊绒制品开发过程中的相关参数作了分析。通过极限捻度试验分析认为,常规精纺羊绒单纱捻系数以110~130为宜,倍捻的复合方式以常规S捻为主;而捻系数、弹力丝对织物起球的影响为:对低捻系数的羊绒织物有轻微影响,而对高捻系数的织物影响不明显;对于精纺羊绒纱线,存在纱线的强力极限捻系数比伸长极限捻系数偏大约10个捻系数的情况。     

空气导管承载特性的有限元计算

空气导管的垂向、偏转承载特性是衡量空气导管设计优劣的重要指标,本文通过建立空气导管的有限元分析模型,利用ABAQUS软件分析空气导管的垂向、偏转承载特性及其相应承载工况下的变形趋势,为新型空气导管的研究开发提供了可靠的设计依据。     

具有变量范围约束的潮流算法在OPF中的应用

提出一类新的电力系统最优潮流(OPF)算法.运用函数变换法模拟变量不等式约束,建立具有变量范围约束的潮流方程,并将目标函数与其上限值构成优化目标方程,与变量范围约束潮流方程一起组成扩展的变量范围约束潮流方程.该方程为非线性不定方程组.逐次收缩目标函数上限值,运用广义逆矩阵和牛顿-拉夫逊法求解,将OPF问题转化为一系列求解非线性不定方程组的一维优化逼近过程.介绍了以最小发电费用为目标的潮流优化问题和以最小有功网损为目标的无功优化问题的新算法,通过实例验证了算法的实用性.