Natural Polysaccharides as Multifunctional Components for One-Step 3D Printing Tough Hydrogels

Natural polysaccharides (NPS) are regarded as biomolecular and structural components for preparing high-performance tough hydrogels. But the one-step fabrication of NPS-containing hydrogels in seconds and the template-free design of complicated high-resolution structures are still significant challenges in this field. To meet these requirements, various NPS-containing tough hydrogels are fabricated and processed into 2D/3D structures via the combination of Ru(bpy)₃²⁺-mediated photochemistry and extrusion 3D printing technique. The whole fabrication process is one-step, completed in tens of seconds under visible light irradiation. It is found that the used NPS plays a key role in achieving the fabrication of high-performance structured tough hydrogels. The high reactivity of functional groups in the used NPS can shorten their gelation times. Long rigid chains of the used NPS, their hierarchical assemblies, and contrasting multinetworks benefit from the efficient dissipation of mechanical energy and enhancement of its operational stability. Strong supramolecular interactions enable hydrogel precursors to have high viscosities, therefore providing good controllability to design high-resolution and complicated tough hydrogel structures via extrusion 3D printing. It is anticipated that this straightforward fabrication strategy and findings will open new horizons for NPS-containing materials.     

Tough Transient Ionic Junctions Printed with Ionic Microgels

Emerging soft ionotronics better match the human body mechanically and electrically compared to conventional rigid electronics. They hold great potential for human-machine interfaces, wearable and implantable devices, and soft machines. Among various ionotronic devices, ionic junctions play critical roles in rectifying currents as electrical p–n junctions. Existing ionic junctions, however, are limited in electrical and mechanical performance, and are difficult to fabricate and degrade. Herein, the design, fabrication, and characterization of tough transient ionic junctions fabricated via 3D ionic microgel printing is reported. The 3D printing method demonstrates excellent printability and allows one to fabricate ionic junctions of various configurations with high fidelity. By combining ionic microgels, degradable networks, and highly charged biopolymers, the ionic junctions feature high stretchability (stretch limit 27), high fracture energy (>1000 Jm⁻²), excellent electrical performance (current rectification ratio >100), and transient stability (degrade in 1 week). A variety of ionotronic devices, including ionic diodes, ionic bipolar junction transistors, ionic full-wave rectifiers, and ionic touchpads are further demonstrated. This study merges ionotronics, 3D printing, and degradable hydrogels, and will motivate the future development of high-performance transient ionotronics.     

急倾斜煤层群坚硬顶板导爆索爆破放顶试验

淮南孔集煤矿在有煤尘爆炸危险及项板坚硬的采空区内进行中深孔挤压爆破时，在国内率先应用煤矿安全导爆索代替多雷管起爆，成功地进行了22次爆破，解决了生产急需，获得了较好的技术经济效果．并在导爆索起爆性能测定、操作工艺及在有煤尘爆炸危险的采空区内如何安全爆破等方面取得了经验．     

环氧丙烯酸/聚氨酯丙烯酸酯共混体系的紫外光固化及力学性能的研究

采用紫外光固化的不同类型聚氨酯丙烯酸酯对环氧丙烯酸酯进行了增韧改性。利用索氏提取法研究了共混体系的紫外光固化行为。DSC和TGA对共混体系的热学性能研究表明：共混体系的相容性良好，且热分解温度比纯环氧丙烯酸酯提高了19℃。测试了共混体系的力学性能并利用SEM对冲击断面形貌进行了观察。找出并初步探讨了聚氨酯丙烯酸酯增韧环氧丙烯酸酯的微观机理。试验表明：当聚氨酯丙烯酸酯用量为3．6％时，体系的冲击性能可提高300％以上。     

VB6.0在饼干炉温度的巡检运用

在自动控制和巡回检测系统中，需要进行数据通信，VB6．0已成为Windows98系统开发的主要语言，以其高效、简单易用等特点，解决数据通讯等问题，以下开放的这套系统有16个采集点，反映了饼干炉整体温度的变化范围，趋势等数据，发生数据传输冲突的可能性很大，这就要求，数据发送必须有先后次序的约定，本文提供了利用VB6．0编程工具来解决这个问题。     

半圆形深槽带式输送机的研究

研究半圆形深槽带式输送机可以实现大倾角输送的工作原理 ,并得出了半圆形深槽带式输送机的基本设计原则 ;在理论分析的基础上 ,给出了合理的托辊组布置方案 ;通过半圆形深槽带式输送机与其他形式带式输送机的比较 ,总结了半圆形深槽带式输送机的特点。     

改性菠萝皮渣膳食纤维添加对饼干品质的影响

为研究改性菠萝皮渣膳食纤维对饼干品质的影响,以改性菠萝皮渣膳食纤维为原料,添加到饼干中,测定饼干面团流变特性、饼干的理化性质以及感官特性。结果表明:随着改性菠萝皮渣膳食纤维添加量的增加,面团的弹性和黏性逐渐增加,呈现出弹性流体特性;饼干硬度、脆性和咀嚼性增加,弹性和回复性减小;饼干的明度和亮度降低,黄色调下降,红色调上升,颜色相对偏暗。当改性菠萝皮渣膳食纤维添加量为7%时,饼干品质最佳,饼干硬度为3158.73±46.30 g,脆性为2648.08±49.62 g,弹性为0.33±0.04,咀嚼性为3834.66±72.57 g,回复性为0.18±0.02,口感较适宜,感官评分为78.8±3.4分,接受度最好。     

冲印饼干机成型机构优化分析

合理设计冲印饼干机成型机构的结构参数和安装参数,是保证获得均匀一致和图案清晰的高质量饼干生坯的关键环节,本文在分析冲印饼干机基本结构和工作原理的基础上,系统分析了冲印饼干机成型机构各杆件运动学特征,推导了各杆件的运动方程,并以冲头水平分速度与面坯输送带运动速度最小为目标函数,对冲印饼干机成型机构各杆件的结构参数及安装参数进行了优化分析,建立了冲印饼干机成型机构优化设计的数学模型,所建优化数学模型对提高冲印饼干机成型机构设计效率和可靠性具有重要的指导意义。     

儿童促消化酥性饼干的研制

鸡内金、陈皮、山楂是具有促消化作用的天然物质,采用L9（33）正交试验法确定它们在酥性饼干中的添加量,研制具有促消化功能的儿童酥性饼干。在基本配方的基础上确定的最佳配方为：鸡内金0.5%,陈皮1.5%,山楂10.0%。     

环氧丙烯酸酯增韧间苯二甲酸二烯丙酯树脂体系的聚合反应及断面形态

采用环氧丙烯酸酯 (VE)为间苯二甲酸二烯丙酯 (DAIP)树脂的增韧剂 ,体系的韧性得到改善。利用 DSC、FTIR等方法进一步研究了 DAIP/ VE体系的聚合反应 ,证明改性体系中存在两个反应阶段 ;前一阶段即低温固化阶段 ,主要为 VE与 DAIP的共聚反应以及少量 VE的自聚反应 ;后一阶段即高温固化阶段 ,主要为 DAIP的自聚反应。改性体系与未改性体系相比 ,断面形态结构更为多样。