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1.
Zheng Xinyan Hu Po Yao Ruxian cheng Jinhe Chang Yiheng Wu Haitao Mei Hongying Sun Shuxiang Chen Qingtai liu Fang Chen Shujing Wen Hua 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(5):2217-2226
Journal of Radioanalytical and Nuclear Chemistry - Enhancement of U(VI) biomineralization by Saccharomyces cerevisiae through addition of inorganic phosphorus was studied in this work. The addition... 相似文献
2.
Pirozerskii A. L. Charnaya E. V. Lee M. K. Chang L.-J. Naumov S. V. Domozhirova A. N. Marchenkov V. V. 《Physics of the Solid State》2022,64(2):80-84
Physics of the Solid State - The discovery of extreme magnetoresistance (MR) in nonmagnetic materials attracted attention to WTe2 semimetal. We studied MR in a single crystal of tungsten... 相似文献
3.
Bohuai Xiao Jianqiao Dong Zhiye Wang Xu Wang Mingjun Sun Jing Guo Gongming Qian Yunchuan Li Shuai Chang 《Chemphyschem》2022,23(7):e202100833
One important prerequisite for the fabrication of molecular functional device strongly relies on the understanding the conducting behaviors of the metal-molecule-metal junction that can respond to an external stimulus. The model Lewis basic molecule 4,4′-(pyridine-3,5-diyl)dibenzonitrile (DBP), which can react with Lewis acid and protic acid, was synthesized. Then, the molecular conducting behavior of DBP, DBP-B(C6F5)3, and DBP-TfOH (DBP-B(C6F5)3, and DBP-TfOH were produced by Lewis acid and protonic acid treatment of DBP) was researched and compared. Given that their identical physical paths for DBP, DBP-B(C6F5)3, and DBP-TfOH to sustain charge transport, our results indicate that modifying the molecular electronic structure, even not directly changing the conductive physical backbone, can tune the charge transporting ability by nearly one order of magnitude. Furthermore, the addition of another Lewis base triethylamine (of stronger alkaline than DBP), to Lewis acid-base pair reverts the electrical properties back to that of a single DBP junction, that is constructive to propose a useful but simple strategy for the design and construction of reversible and controllable molecular device based on pyridine derived molecule. 相似文献
4.
近年来深度卷积神经网络在可见光船舶检测方面取得了显著的进展,然而,大多数相关研究是通过改进大型的网络结构来提高检测性能,因此加大了对更高计算机性能的需求。此外,可见光图像难以在云、雾、海杂波、黑夜等复杂场景检测到船舶。针对以上问题,提出了一种融合红(red, R)、绿(green, G)、蓝(blue, B)和近红外(NIR)4个波段光谱信息的由粗到精细的轻量型船舶检测算法。与现有的方法中根据光谱特性利用水体检测算法提取水体区域不同之处是该算法是利用改进的水体检测算法来提取船舶候选区域。为获取更准确的候选区域,对船舶、厚云、薄云、平静海面、杂波海面5种场景中4个波段的像素值进行了统计分析,选取近红外大于阈值作为辅助判断,并以其中心点获取候选区域32×32大小的切片,并对切片进行非极大值抑制,由此获得了船舶粗检测结果。随后构建了轻量级LSGFNet网络对船舶候选区域切片进行精细识别。构建的网络融合了1×1卷积提取的波谱特征与3×3的提取几何特征,为防止光谱特征与几何特征的信息在融合时“信息不流通”,在LSGFNet网络中引入了ShuffleNet中的通道打乱机制,并减小了模型结构,与典型的轻量级网络相比具有更好的效果且模型较小。最后,利用Sentinel-2卫星多光谱10 m分辨率数据构建了512×512大小的1 120组数据进行粗检测,以及32×32大小的6 014组数据进行精细网络训练,其中候选区域粗提取的查全率为98.99%,精细识别网络精确度为96.04%,不同场景下的平均精确度为92.98%。实验表明该算法在抑制云层、海浪杂波等干扰的复杂背景下具有较高的检测效率,且训练时间短、计算机性能需求低。 相似文献
5.
Zhang Yi Huang Peng Long Mei Liu Song Yang Huaming Yuan Shuwen Chang Shi 《中国科学:化学(英文版)》2019,62(1):58-61
An innovative cancer therapy strategy regarding the interface engineering of kaolinite has been designed. The exposed silanol group facilitates more guest species with high dispersion on the supports. Mn_3O_4 magnetic nanoparticles are uniformly distributed on external surfaces of the Kaolin_(C12N)with the Al–O–Mn bond for the detection of the tumor microenvironment by T1-MRI; Doxorubicin(DOX) are loaded in the interlayer space with the electrostatic interaction for chemo-treating; and KI is coated on the outer layer of the nanocomposites based on the electrostatic interaction for thyroid cancer targeting. The synergetic effects and the treatment mechanism enhanced by the interface engineering, KI@DOX-Mn_3O_4-Kaolin_(C12N)can cause remarkably low cell viability(57%, 200 μg/mL), tumor shrinking(75%, 20 μg/kg), and accumulation into the tumor tissues. The novel kaolinite based drug delivery system is expected to incorporate imaging diagnosis, targeted therapy and drug delivery into one single system for postoperative residual thyroid cancer treatment and observation for metastasis of focal area. 相似文献
6.
Peter T. Smith Younghoon Kim Dr. Bahiru Punja Benke Prof. Kimoon Kim Prof. Christopher J. Chang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(12):4932-4937
We report a supramolecular strategy for promoting the selective reduction of O2 for direct electrosynthesis of H2O2. We utilized cobalt tetraphenylporphyrin (Co-TPP), an oxygen reduction reaction (ORR) catalyst with highly variable product selectivity, as a building block to assemble the permanently porous supramolecular cage Co-PB-1(6) bearing six Co-TPP subunits connected through twenty-four imine bonds. Reduction of these imine linkers to amines yields the more flexible cage Co-rPB-1(6). Both Co-PB-1(6) and Co-rPB-1(6) cages produce 90–100 % H2O2 from electrochemical ORR catalysis in neutral pH water, whereas the Co-TPP monomer gives a 50 % mixture of H2O2 and H2O. Bimolecular pathways have been implicated in facilitating H2O formation, therefore, we attribute this high H2O2 selectivity to site isolation of the discrete molecular units in each supramolecule. The ability to control reaction selectivity in supramolecular structures beyond traditional host–guest interactions offers new opportunities for designing such architectures for a broader range of catalytic applications. 相似文献
7.
Dr. Yuan Liu Dr. Jin-Cheng Liu Teng-Hao Li Zeng-Hui Duan Dr. Tian-Yu Zhang Ming Yan Dr. Wan-Lu Li Prof. Dr. Hai Xiao Prof. Dr. Yang-Gang Wang Prof. Dr. Chun-Ran Chang Prof. Dr. Jun Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(42):18745-18749
The direct, nonoxidative conversion of methane on a silica-confined single-atom iron catalyst is a landmark discovery in catalysis, but the proposed gas-phase reaction mechanism is still open to discussion. Here, we report a surface reaction mechanism by computational modeling and simulations. The activation of methane occurs at the single iron site, whereas the dissociated methyl disfavors desorption into gas phase under the reactive conditions. In contrast, the dissociated methyl prefers transferring to adjacent carbon sites of the active center (Fe1©SiC2), followed by C−C coupling and hydrogen transfer to produce the main product (ethylene) via a key −CH−CH2 intermediate. We find a quasi Mars–van Krevelen (quasi-MvK) surface reaction mechanism involving extracting and refilling the surface carbon atoms for the nonoxidative conversion of methane on Fe1©SiO2 and this surface process is identified to be more plausible than the alternative gas-phase reaction mechanism. 相似文献
8.
Wei Wei Shu-Hua Yang Ze-Han Bao Chong Zhang Chang Gao Wei-Ru Fan 《中国物理C(英文版)》2020,44(9):094104-094104-10
9.
Ajay Gupta Fillip Kumar Sarkar Rajib Sarkar Ramen Jamatia Chang Yeon Lee Gajendra Gupta Amarta Kumar Pal 《应用有机金属化学》2020,34(9):e5782
Magnetically retrieval CuFe2O4@MIL-101(Cr) metal–organic framework was successfully prepared from easily available starting materials and characterized using various spectroscopic and analytical techniques such as powder X-ray diffraction, scanning electron microscopy, energy dispersive X-ray, transmission electron microscopy, elemental mapping, Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller, vibrating sample magnetometer, and inductively coupled plasma optical emission spectroscopy. The catalyst was then used in the synthesis of benzodiazepines containing a triazole moiety in water. The advantages of this protocol include high yields, reusability of the catalyst, and gram-scale synthesis. 相似文献
10.
Rongzhen Wu Hongyu Chen Dr. Ninghui Chang Yuzhi Xu Prof. Dr. Jiao Jiao Prof. Dr. Hailong Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(6):1166-1195
Bryostatins are a class of naturally occurring macrocyclic lactones with a unique fast developing portfolio of clinical applications, including treatment of AIDS, Alzheimer's disease, and cancer. This comprehensive account summarizes the recent progress (2014–present) in the development of bryostatins, including their total synthesis and biomedical applications. An emphasis is placed on the discussion of bryostatin 1 , the most-studied analogue to date. This review highlights the synthetic and biological challenges of bryostatins and provides an outlook on their future development. 相似文献