中空涤纶/不锈钢/竹炭保温透湿材料的开发及性能研究

通过花式捻线方法将中空涤纶、不锈钢长丝和竹炭纤维三种功能性纤维并捻获得复合纱线,利用纱线强度、毛羽和实际捻度测试,得到最佳的纱线纺制参数。并采用最佳工艺参数纺制的包绕纱线进行平纹织物织造,对其织物透湿性、远红外发射率以及保温性能进行测试表征,最终制备一种可用于防寒服的新型保温透湿织物。结果表明,缠绕捻度为上捻度200,下捻度0时,纺制的包芯纱具有最佳捻度。中空涤纶/不锈钢/竹炭织物透湿率为5 184g/(m2·24h),达到透湿织物透湿要求的2倍以上。一至四层织物的远红外发射率均在70%及以上,符合远红外发射率具有功能性结果的范围。织物克罗值达到7.355clo,高于极低温作业穿着克罗值51.6%,可满足极低温环境下的织物保温要求。织物保温率为62.43%,相比于棉、毛等传统纺织原料,织物保温率可以提升2倍以上。     

Novel transcatheter aortic heart valves exhibiting excellent hemodynamic performance and low-fouling property

Transcatheter aortic heart valves (TAHVs) have been widely used for aortic valve replacements, with less trauma and lower clinical risk compared with traditional surgical heart valve replacements. In the present study, composites of poly(ethylene glycol) diacrylate (PEGDA) hydrogels and anisotropic high-shrinkage polyethylene terephthalate/polyamide6 (PET-PA6) fabric (PEGDA/PET-PA6) were fabricated as artificial heart valve leaflets. Dynamic mechanical analyses (DMA) indicated that PEGDA/PET-PA6 composites possessed anisotropic mechanical properties (i.e., storage moduli ～23.30 ± 1.36 MPa parallel to the aligned fabric fibers and ～9.68 ± 0.90 MPa perpendicular to the aligned fibers at 1 Hz) that were comparable to aortic valve leaflets. The PEGDA/PET-PA6 composites with smooth surfaces were highly hydrophilic (contact angle ～41.6° ± 3.8°) and had low-fouling properties without platelet adhesion, suggesting a low risk of thrombogenicity when they interacted with blood. Furthermore, transcatheter aortic heart valves were fabricated using nitinol self-expanding frames and PEGDA/PET-PA6 composites as artificial leaflets, which presented excellent hemodynamic performance with a large orifice area (1.75 cm²) and low regurgitation (3.41%), thus meeting the requirements of ISO 5840-3 standard. Therefore, PEGDA/PET-PA6 composites had suitable mechanical properties, good biocompatibility, and low-fouling properties, indicating that they might be used for TAHVs in the future.     

A DLT-based framework for secure IoT infrastructure in smart communities

In the field of smart communities, significant progress has been made in recent years. The objective of constructing smart communities is to improve the quality of life of their inhabitants. To accomplish this objective, technologies such as Internet of Things (IoT) and Artificial Intelligence (AI) were deployed. The data gathered and processed by IoT devices, particularly those with centralized control, are however susceptible to availability, integrity, and privacy risks. Due to its inherent properties of transparency, immutability, and underlying secure-by-design architecture, Distributed Ledger Technology (DLT) and Smart Contracts enable distributed, decentralized, automated workflows that can be incorporated to automate the management of the next generation of IoT networks. Using a potential use case, a conceptual architecture for securing smart communities with DLT is developed and explained. In this paper, a framework for IoT eco-systems is proposed that provides seamless integration between IoT and DLT to create a decentralized trusted architecture that ensures the trustworthiness of IoT eco-systems at design time and a trust reputation model based on the architecture to protect it at run-time. In addition, the initial implementation steps are described for this framework.     

我国童装设计的现状分析及应对策略初探

儿童的问题已经引起国人的日益关注,而我国童装业起步较晚,存在着各种问题,文章分析了我国童装设计中存在的主要问题及原因,在此基础上,结合童装的特点,提出了若干应对策略。     

典型ATM交换结构分析与交换机设计分类

目前的通信网正逐步向宽带化、综合化和智能化方向发展,为了传送高清晰度电视(HDTV)图像及高速数据,要求通信网高速宽带化。高速宽带通信与现有的电话及数据通信相比,应具有极宽的通信频带(几十Mbps以上)。另一方面,随着科技的发展,人们对通信的需求不断增加,导致未来通信业务的不确定性。因此,人们致力于研究新的通信方式以适应上述情况,其中,ATM可能是实现宽带ISDN的最佳方式,可以满     

iLQF调度算法及其参数的仿真

文章介绍一种无内部阻塞ATM交换结构的输入缓存模型及其缓存信元的iLQF调度算法(即迭代的最长队列优先调度算法),并具体给出该算法的实现方案。通过仿真,分析和确定了交换结构的输入缓存长度和iLQF调度算法的迭代次数对信元丢失率的影响。     

三维编织复合材料预制件表面图象计算机分析系统

介绍了三维编织复合材料预制件表面图像检测与纹理分析的 基本原理。该系统以CCD为传感器,与微型计算机连接,进行三维编织复合材料预制件表面 编织角的检测。本系统对改善三维编织复合材料预制件的加工工艺具有指导作用,同时也为 纺织复合材料新的性能指标建立提供了有利条件,为纺织复合材料在各个领域的广泛应用提 供理论基础。     

等离子体协同纤维素酶对亚麻织物性能的影响

为了提高亚麻织物的染色性能,采用空气低温等离子体和等离子体与纤维素酶协同处理工艺对亚麻织物进行改性,并选用天然苏木染料对其进行染色,探讨了等离子体真空度、功率和处理时间以及协同工艺对亚麻织物染色性能的影响。结果表明,最佳的等离子体处理工艺为真空度0.02 MPa、功率90W、处理时间3min。等离子体与纤维素酶协同处理对亚麻织物苏木染料的染色性能优于单独使用等离子体或酶处理工艺,并且其摩擦牢度和耐皂洗牢度均比未处理和单独使用等离子体或酶处理工艺的亚麻织物高1级左右。     

聚四氟乙烯薄膜复合蒸呢包布及其应用性能

为了提高羊毛精纺面料的表面光泽及其耐久性,采用聚四氟乙烯（PTFE）微孔薄膜与传统包布复合研制新型复合蒸呢包布,测试采用新型复合包布罐蒸后毛织物的各项性能。结果表明;PTFE微孔薄膜的结构对复合包布的透湿量影响较小;采用复合包布经一次罐蒸的毛织物,其表面平整性、尺寸稳定性、力学性能、表面光泽都优于采用传统包布一次罐蒸的毛织物;采用复合包布经两次罐蒸的毛织物的表面平整性、尺寸稳定性、力学性能、表面光泽基本达到传统包布经罐蒸→电压→罐蒸的织物的效果。     

基于OpenGL的纬编针织物三维仿真真实感的研究

根据纱线结构形态特征,采用圆柱体结构来模拟纱线.借助NURBS曲线的可控性,建立纬编针织物三维线圈结构模型.利用Visual C++和OpenGL开发工具模拟仿真纬编针织物线圈结构,同时对线圈模型进行光照、材质、纹理结构的处理,开发仿真程序,实现了纬编针织物的三维仿真.由得到的效果图可以看出,OpenGL仿真结果与实际线圈结构十分相似,具有良好的真实感.