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851.
《Arabian Journal of Chemistry》2022,15(12):104331
The synthesis of nontoxic plasticizers derived from the waste residues of the rosin-processing industry can reduce pollution and promote the high-value utilization of the waste residues of rosin. In this study, four kinds of sustainable branched plasticizers derived from a biomass resource, eugenol (derived from the waste residues of the rosin processing industry), were synthesized via one-pot solvent free polymerization and used to plasticize polyvinyl chloride (PVC). Internally plasticized PVC was fabricated using thiolated DPE (branched plasticizers based on eugenol). The thermal stability, tensile properties, microstructure, volatility behavior, and solvent extraction resistance of plasticized PVC were investigated. Compared with the behavior of the commercial plasticizer dioctyl phthalate, the thermal stability, plasticizing efficiency, and migration resistance of the branched plasticizers are superior. The acute oral toxicity dose of each branched plasticizer was extremely high at 5000 mg/kg of body weight, with no deaths among test animals. Compared with externally plasticized PVC, the internally plasticized PVC showed zero weight loss in volatility and leaching tests despite its less effective plasticization. All the branched plasticizers have potential application in plastic products. 相似文献
852.
K-ion batteries (KIBs) attract considerable attention due to the abundance of K, high-working voltages, and chemical similarity with Li, enabling the utilization of mature Li-ion technology. However, shortage of high-performance anode materials is a critical obstacle for the development of KIBs. Through first-principles swarm-intelligence structural search, we identify a potential anode material, the C6S monolayer, which provides not only a remarkably high specific capacity of 1546 mAh/g but also a low diffusion barrier of 0.11 eV and a low open-circuit voltage of 0.21 V. Inherent metallicity originates from delocalized π electrons. 相似文献
853.
Dr. Xiaoxiao Wang Dr. Nanping Deng Dr. Liying Wei Dr. Qi Yang Dr. Hengying Xiang Dr. Meng Wang Prof. Bowen Cheng Prof. Weimin Kang 《化学:亚洲杂志》2021,16(19):2852-2870
Lithium-sulfur (Li−S) batteries, possessing excellent theoretical capacities, low cost and nontoxicity, are one of the most promising energy storage battery systems. However, poor conductivity of elemental S and the “shuttle effect” of lithium polysulfides hinder the commercialization of Li−S batteries. These problems are closely related to the interface problems between the cathodes, separators/electrolytes and anodes. The review focuses on interface issues for advanced separators/electrolytes based on nanomaterials in Li−S batteries. In the liquid electrolyte systems, electrolytes/separators and electrodes system can be decorated by nano materials coating for separators and electrospinning nanofiber separators. And, interface of anodes and electrolytes/separators can be modified by nano surface coating, nano composite metal lithium and lithium nano alloy, while the interface between cathodes and electrolytes/separators is designed by nano metal sulfide, nanocarbon-based and other nano materials. In all solid-state electrolyte systems, the focus is to increase the ionic conductivity of the solid electrolytes and reduce the resistance in the cathode/polymer electrolyte and Li/electrolyte interfaces through using nanomaterials. The basic mechanism of these interface problems and the corresponding electrochemical performance are discussed. Based on the most critical factors of the interfaces, we provide some insights on nanomaterials in high-performance liquid or state Li−S batteries in the future. 相似文献
854.
Pan Wang Dr. Jian-Wei Wang Prof. Wen-Hua Zhang Dr. Hongzhen Bai Prof. Guping Tang Prof. David J. Young 《化学:亚洲杂志》2021,16(19):2993-3000
Nanoformulations of mononuclear Pt complexes cis-PtCl2(PPh3)2 ( 1 ), [Pt(PPh3)2(L−Cys)] ⋅ H2O ( 3 , L−Cys=L-cysteinate), trans-PtCl2(PPh2PhNMe2)2 ( 4 ; PPh2PhNMe2=4-(dimethylamine)triphenylphosphine), trans-PtI2(PPh2PhNMe2)2 ( 5 ) and dinuclear Pt cluster Pt2(μ-S)2(PPh3)4 ( 2 ) have comparable cytotoxicity to cisplatin against murine melanoma cell line B16F10. Masking of these discrete molecular entities within the hydrophobic core of Pluronic® F-127 significantly boosted their solubility and stability, ensuring efficient cellular uptake, giving in vitro IC50 values in the range of 0.87–11.23 μM. These results highlight the potential therapeutic value of Pt complexes featuring stable Pt−P bonds in nanocomposite formulations with biocompatible amphiphilic polymers. 相似文献
855.
低成本、高性能的钠离子电池有望成为代替锂离子电池的下一代核心器件.但是开发出高比容量、高倍率的钠离子电池负极材料依然是瓶颈.本文通过水热/溶剂热法制备了Co基前驱体,然后将其一步硫/磷热处理制得具有空心多孔结构的h-Co9S8/CoP/C纳米复合材料.通过X-射线粉末衍射(XRD)、拉曼光谱(Raman)、扫描电镜(SEM)、透射电镜(TEM)和X-射线光电子能谱(XPS)等表征以确定纳米复合物的物相以及形貌特征.当h-Co9S8/CoP/C作为钠离子电池负极材料时,该电极材料展示了高的比容量(561 mAh g-1@0.1 Ag-1)、较好的循环性能(可逆比容量200 mAh g-1@2 Ag-1)和倍率性能.h-Co9S8/CoP/C之所以显示出良好的储钠性能,主要得益于其空心多孔结构不仅提供更多的空间缓解钠在反复嵌入和脱出过程造成的体积膨胀效应,而且可以缩短离子/电荷扩散途径以加快反应动力学,此外,Co9S8、CoP和C独特的电子结构优势得以共同发挥. 相似文献
856.
Wurood kh. Al-lehaibi Khulood A. Al-makhzomi Hani Sh. Mohammed Hamid Hammad Enezei Mohammad Khursheed Alam 《Molecules (Basel, Switzerland)》2021,26(7)
Background: The study examined the oral microbiota, physiological and immunological changes in patients using thermoplastic retainers during three months of use. Methods: The study included several steps. Firstly, 10 swabs were collected from the buccal and palatal surfaces of the teeth of the patients, approximately 2 mL of saliva was collected from the same patients and 2 mL of saliva was collected from 10 healthy people to measure the pH and secretory IgA level. This was followed by the isolation and identfication of the bacterial isolates in the patient samples. Then, isolate susceptibility toward chlorhexidine (CHX) and their adhesion ability to thermoplastic retainer surfaces was measured. In addition to that the study estimated the numbers of Lactobacillus and Streptooccus mutans colonies during three months and finally, a comparsion of pH acidity and IgA level between the patients and healthy people was performed. The results showed the predominant bacteria during the three months were Lactobacillus spp. and Streptococcus spp. followed by different rates of other bacteria. Raoultella ornithinolytica showed more resistance to CHX while Lactobacillus spp. showed more sensitivity. Streptococcus mutans colony levels were higher than Lactobacillus spp. colonies during the three months, also S. mutans had the highest value in adherence to retainer thermoplastic. Finally, pH acidity showed a highly significant difference (p ≤ 0.05) in the third month, like IgA levels (p ≤ 0.05). Conclusions: According to the results obtained from the current study, the researchers noted that the thermoplastic retainers helped change the oral cavity environment. 相似文献
857.
Hideyasu China Nami Kageyama Hotaka Yatabe Naoko Takenaga Toshifumi Dohi 《Molecules (Basel, Switzerland)》2021,26(7)
We report a convenient and practical method for the preparation of nonexplosive cyclic hypervalent iodine(III) oxidants as efficient organocatalysts and reagents for various reactions using Oxone® in aqueous solution under mild conditions at room temperature. The thus obtained 2-iodosobenzoic acids (IBAs) could be used as precursors of other cyclic organoiodine(III) derivatives by the solvolytic derivatization of the hydroxy group under mild conditions of 80 °C or lower temperature. These sequential procedures are highly reliable to selectively afford cyclic hypervalent iodine compounds in excellent yields without contamination by hazardous pentavalent iodine(III) compound. 相似文献
858.
《Journal of Saudi Chemical Society》2021,25(9):101320
A highly efficient arylation of para-quinone methides (p-QMs) with N,N-dimethylaniline under solvent free condition has been developed, which proceeded via a para-toluenesulfonic acid (TsOH)-promoted 1,6-conjugated addition pathway. This methodology provided a green and sustainable methodology to construct various novel unsymmetrical triarylmethanes (TAMs) with the advantages of good functional group tolerance, scalability, and regioselectivity. 相似文献
859.
860.
强冲击下的物质变形、破坏及诱发的轻重介质混合问题,是内爆压缩科学和工程应用领域的研究重点.本文针对爆轰波对碰条件下的复杂加载动力学过程及其动载破坏形态特征,开展数值模拟研究与极曲线理论分析.设计了爆轰波对碰驱动平面锡飞层的计算模型,获得了爆轰加载动力学过程及波系相互作用物理图像,分析了锡飞层对碰区自由表面速度历史的典型特征.给出了锡飞层中折射激波对碰发生马赫反射的临界条件,解读了三波结构的传播行为,阐明了对碰区内存在"一维正冲击"区域,一维区外存在单次斜冲击向两次斜冲击过渡的复杂加载动力学过程,提出了对碰区冲击动力学模型,揭示了影响对碰区动载行为特征的机理.数值模拟结果与极曲线理论分析结果相互印证,符合较好.本文的研究成果,将为深入理解和解读对碰区特殊的物质破坏及混合现象提供重要的理论支撑. 相似文献