新型绝缘树脂及应用

本文介绍了FUCHEM系列无溶剂绝缘树脂的性能及应用，着重探讨了产品的阻燃、低收缩、高耐腐蚀、高耐热等级等特性。     

Investigation on the properties of a three‐component copolymer consisting of tris(allylphenoxy) triazine monomer and a diamine‐chain‐extension bismaleimide

A new type of modified bismaleimide resin was obtained by copolymerization between tris(allylphenoxy)triazine monomer (TAPT) and an aromatic diamine‐chain‐extension bismaleimide [e.g., 4,4′‐diaminodiphenylmethane (DADPM)‐chain‐extension 4,4′‐bismaleimidodiphenylmethane (BMDPM)]. The new three‐component‐polymer system had good processibility and mechanical properties. Better results were obtained when the weight ratio of TAPT to the DADPM‐chain‐extension BMDPM resin was 30%. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 475–480, 2004     

新型绝缘树脂的应用

本文介绍了FUCHEM系列无溶剂绝缘树脂的性能及应用，着重探讨了产品的阻燃，低收缩，高耐腐蚀，高耐热等级等特性。     

载锰氮化碳催化臭氧法降解水中草酸研究

草酸是废水中多种有机物氧化降解的中间产物,与臭氧反应速率很低,难以直接氧化去除。本研究通过热解法煅烧不同摩尔比例的三聚氰胺与醋酸锰(Ⅲ)二水合物,制备出不同负载量的载锰氮化碳催化剂,并研究了不同条件下载锰氮化碳催化臭氧法对草酸的降解效果,考察三聚氰胺与醋酸锰摩尔比、催化剂投加量、p H值、臭氧浓度等因素以及叔丁醇对草酸去除效果的影响。实验结果表明:相对于单独臭氧氧化而言,载锰氮化碳催化臭氧法可以极大的提高草酸的去除率,在投加0.15 g/L三聚氰胺与醋酸锰20∶1的催化剂后,草酸在60 min的TOC去除率可达到89.1%。叔丁醇加入对草酸的去除率影响较小,表明·OH在载锰氮化碳催化氧化草酸的过程中起作用但不是唯一因素。     

On the complexity of role updating feasibility problem in RBAC

In Role Based Access Control (RBAC) systems, it is necessary and important to update the role–permission assignments in order to reflect the evolutions of the system transactions. However, role updating is generally complex and challenging, especially for large-scale RBAC systems. This is because the resulting state is usually expected to meet various requirements and constraints. In this paper, we focus on a fundamental problem of role updating in RBAC, which determines whether there exists a valid role–permission assignment, i.e., whether it can satisfy all the requirements of the role updating and without violating any role–capacity or permission–capacity constraint. We formally define such a problem as the Role Updating Feasibility Problem (RUFP), and study the computational complexity of RUFP in different subcases. Our results show that although several subcases are solvable in linear time, this problem is NP-complete in the general case.     

Efficient object detection based on selective attention

In this paper, we make use of biologically inspired selective attention to improve the efficiency and performance of object detection under clutter. At first, we propose a novel bottom-up attention model. We argue that heuristic feature selection based on bottom-up attention can stably select out invariant and discriminative features. With these selected features, performance of object detection can be improved apparently and stably. Then we propose a novel concept of saccade map based on bottom-up attention to simulate the saccade (eye movements) in vision. Sliding within saccade map to detect object can significantly reduce computational complexity and apparently improve performance because of the effective filtering for distracting information. With these ideas, we present a general framework for object detection through integrating bottom-up attention. Through evaluating on UIUC cars and Weizmann–Shotton horses we show state-of-the-art performance of our object detection model.     

甘油三酸脂对硅溶胶的分散作用

通过对硅溶胶泥浆的流变性实验确定了硅溶胶泥浆的流变模型，验证并分析了加入少量经过低温氧化过的甘油三酸脂（ＧＴＯ）不改变硅溶胶泥浆的流变模型，但能有效地改善其流变性能。因此，ＧＴＯ可作为硅溶胶结合浇注料的高效减水剂。     

盐酸克林霉素合成工艺改进

采用新工艺合成克林霉素,流程短,收率高,重量收率比传统工艺提高了21.55个百分点,可达88.0%,产品质量符合中国药典2000版标准.     

Tensile properties of hollow glass bead‐filled polypropylene composites

The tensile properties of polypropylene (PP) filled with hollow glass beads have been measured at room temperature to identify the effects of the particle contents, size and its distribution on them in the present article. The mean diameters of the fillers were 11, 35, and 70 μm, and they were named as TK10, TK35, and TK70 respectively. The surface of these particles was pretreated with silane coupling agent. The results showed that the yield stress (σ_y) decreased gently for PP/TK70 systems, whereas decreased relatively obviously for PP/TK35 systems with increasing the volume fraction (?_f) of the fillers. When ?_f was less than 5%, the tensile strength at break (σ_b) of the composites increased with the increase of ?_f. When ?_f was more than 5%, σ_b was almost a constant for PP/TK70 systems, while σ_b decreased linearly for PP/TK35 systems. The tensile fracture strain (ε_b) of the composites decreased suddenly when ?_f was less than 5%, and then decreased slightly with increasing ?_f. When ?_f was 10%, σ_y and σ_b increased while ε_b decreased with the increase of the bead diameter. Furthermore, the σ_y was predicted by means an equation proposed in the previous work, and good interfacial adhesion was shown between the hollow glass beads and the matrix. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1697–1701, 2007