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71.
随着我国的经济发展,人们对于住宅建筑的要求也与日俱增。虽然我国建筑设计发展实现设计多样化、人性化,但仍存有不足之处,本文对设计中的问题及完善措施进行了分析研究,为相关工作者提供一定的建议。 相似文献
72.
Mengting He Honglian Yu Yinmin Zhao Jiahui Liu Qi Dong Zhigang Xu Yuejun Kang Peng Xue 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(21):2300244
Energy band structure of inorganic nano-sonosensitizers is usually optimized by surface decoration with noble metals or metal oxide semiconductors, aiming to enhance interfacial charge transfer, augment spin-flip and promote radical generation. To avoid potential biohazards of metallic elements, herein, metal-free graphitic carbon nitride quantum dots (g-C3N4 QDs) are anchored onto hollow mesoporous TiO2 nanostructure to formulate TiO2@g-C3N4 heterojunction. The direct Z-scheme charge transfer significantly improves the separation/recombination dynamics of electron/hole (e−/h+) pairs upon ultrasound (US) stimulation, which promotes the yield of singlet oxygen (1O2) and hydroxyl radicals (·OH). The conjugated g-C3N4 QDs with peroxidase-mimic activity further react with the elevated endogenous H2O2 and aggravate oxidative stress. After loading prodrug romidepsin (RMD) in TiO2@g-C3N4, stimulus-responsive drug delivery can be realized by US irradiation. The disulfide bridge of the released RMD tends to be reduced by glutathione (GSH) into a monocyclic dithiol, which arrests cell cycle in G2/M phase and evokes apoptosis through enhanced histone acetylation. Importantly, reactive oxygen species accumulation accompanied by GSH depletion is devoted to deleterious redox dyshomeostasis, leading to augmented systemic oncotherapy by eliciting antitumor immunity. Collectively, this paradigm provides useful insights in optimizing the performance of TiO2-based nano-sonosensitizers for tackling critical diseases. 相似文献
73.
Xiaojun Sun Mengting Di Jie Liu Li Gao Xiaoming Yan Gaohong He 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(44):2303757
Covalent organic frameworks (COFs) are porous crystalline polymeric materials formed by the covalent bonding of organic units. The abundant organic units library gives the COFs species diversity, easily tuned pore channels, and pore sizes. In addition, the periodic arrangement of organic units endows COFs regular and highly connected pore channels, which has led to the rapid development of COFs in membrane separations. Continuous defect-free and high crystallinity of COF membranes is the key to their application in separations, which is the most important issue to be addressed in the research. This review article describes the linkage types of covalent bonds, synthesis methods, and pore size regulation strategies of COFs materials. Further, the preparation strategies of continuous COFs membranes are highlighted, including layer-by-layer (LBL) stacking, in situ growth, interfacial polymerization (IP), and solvent casting. The applications in separation fields of continuous COFs membranes are also discussed, including gas separation, water treatment, organic solvent nanofiltration, ion conduction, and energy battery membranes. Finally, the research results are summarized and the future prospect for the development of COFs membranes are outlined. More attention may be paid to the large-scale preparation of COFs membranes and the development of conductive COFs membranes in future research. 相似文献
74.
Xuewen Zhao Mengyue Gu Rui Zhai Yuhao Zhang Mengting Jin Yanhao Wang Jiangfan Li Yonghong Cheng Bing Xiao Jinying Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(41):2370334
Violet phosphorus (VP), a recently confirmed layered elemental structure, is demonstrated to have unique photoelectric, mechanical, and photocatalytic properties. Element substitution plays a significant role in modifying the physical/chemical properties of semiconducting materials. Herein, antimony is adopted to substitute some phosphorus atoms in VP crystals to tune their physical and chemical properties, resulting in a significantly enhanced photocatalytic hydrogen evolution performance. The antimony-substituted violet phosphorus single crystal (VP-Sb) is synthesized and characterized by single crystal X-ray diffraction (CSD-2214937). The bandgap of VP-Sb has been found to be lowered from that of VP by UV/vis diffuse reflectance spectroscopy and density-functional theory (DFT) calculation, enhancing the optical absorption during photocatalytic reaction. The conducting band minimum of VP-Sb is found to be upshifted from that of VP from measurements and calculation, enhancing its hydrogen reduction activity. The valance band maximum is found to be lowered to weaken its oxidation activity. The edge of VP-Sb is calculated to have an excellent H* adsorption–desorption performance and superior H2 generation kinetics. The H2 evolution rate of VP-Sb is demonstrated to be significantly enhanced to be 1473 µmol h−1 g−1, about five times of that of pristine VP (299 µmol h−1 g−1) under the same experimental conditions. 相似文献
75.
Neural Processing Letters - As one of the most commonly used algorithms in the field of feature extraction, common spatial pattern (CSP) has a good effect on multichannel electroencephalogram (EEG)... 相似文献
76.
为研究水工隧洞在高地温复杂环境下喷层结构的受力特性,以新疆某高地温引水隧洞为依托,采用理论分析和数值模拟的方法,对高地温引水隧洞喷层结构的受力特性进行了研究,并分析了线膨胀系数、围岩不同深度温差以及地应力水平侧压力系数对隧洞喷层结构受力特性的影响。由计算结果可知:在高地温情况下,理论计算的径向压应力最大值为2.07 MPa,环向压应力最大值为35.37 MPa;数值模拟的径向压应力最大值为4.36 MPa,环向压应力最大值为34.37 MPa。通过对比发现:理论计算的径向位移最大值为1.2 mm,环向位移最大值为0.75 mm;数值模拟的径向位移最大值为2.1 mm,环向位移最大值为0.95 mm。数值模拟的结果表明:隧洞围岩喷层结构承受的应力随着线膨胀系数增加会增大;喷层的拱顶与拱底处承受的环向应力随着温差的增加会增大,喷层的拱腰处承受的环向应力随着温差的增加会减小;喷层结构承受的应力随着地应力水平侧压力系数的增加会增大。 相似文献
77.
Mengting Li Changgui Li You Zhou Hua Tian Qiaoyuan Deng Haifang Liu Li Zhu Xueqiong Yin 《应用聚合物科学杂志》2021,138(2):49667
Microencapsulation is a widely-investigated technique used for the unstable material preservation since the wall materials prevent the core materials from loss and deterioration. To improve the stability of cinnamaldehyde (CAL), different microcapsule wall systems are fabricated by spray-drying, and then characterized by experimental methods to determine the most suitable wall materials. Surface morphology, encapsulation efficiency, effective loading capacity, as well as moisture absorption property are evaluated, and the results suggest that a three-matrix system of methyl cellulose (MC)/sodium alginate (SA)/MC or MC/carboxymethyl chitosan (CMC)/SA wall formulation is more suitable for CAL microencapsulation. Moreover, a novel quantitative method is also proposed to verify the most stable wall material microencapsulation. The quantitative results show that the highest activation energy (53.00 ± 2.24 kJ/mol) is observed for the MC/CMC/SA-encapsulated CAL microcapsule. Taken together, the results suggest that MC/CMC/SA wall formulation shows excellent barrier properties and is superior to other wall materials in preventing microencapsulated CAL deterioration. This study will be efficient in designing an ideal capsule for CAL microencapsulation. 相似文献
78.
以聚乳酸(PLA)为基体,羟基磷灰石(HA)作为无机填料,制备含HA质量分数分别为0%、10%和25%的聚乳酸/羟基磷灰石(PLA/HA)复合材料,采用喷雾干燥技术制备复合材料微球。并对其进行微观形貌和结构表征,进一步研究HA质量分数对热稳定性能的影响。傅里叶红外光谱、X射线衍射和X射线光电子能谱测试表明,已成功制备了PLA/HA复合材料微球,其粒径分布在5~11 μm范围内,且随着HA质量分数的增加,复合材料的玻璃化转变温度呈现先降低后升高的趋势,同时其分解温度升高,热稳定性能增加。 相似文献
79.
80.
无组织排放占石化企业挥发性有机物(VOCs)排放的主导地位,排放点多、面广、量大、分散、无规则,总体表现为大型面源或体积源,监测难度很大。本文评述了点、线和面(通量)等VOCs无组织排放监测技术及应用进展,总结了石化企业VOCs无组织排放监测存在的主要问题与难点,提出了石化企业VOCs无组织排放监测体系及适用监测技术。总体上,石化企业VOCs无组织排放监控存在排放清单质量不高、源头监测及溯源困难、排放烟羽及其迁移扩散途径无定形、厂界等开放空间难以封闭监测、常规监测的时间和空间覆盖有限等问题或技术难点,可复合应用点、线、面及通量监测技术,结合常规离线、实时在线、排放通量、移动快速响应等监测设计,构建覆盖排放与环境影响的多元化、网络化、立体化监控体系。未来石化企业VOCs无组织排放监控将向多层级、智能化和大数据应用发展。 相似文献