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排序方式: 共有4468条查询结果,搜索用时 62 毫秒
1.
Dr. Sirinapa Wongwilawan Dr. Doyun Kim Dr. Thien S. Nguyen Wonki Lim Prof. Dr. Sheng Li Prof. Dr. Cafer T. Yavuz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(72):e202202340
Through accumulation, mercury contamination in aquatic systems still poses serious health risks despite the strict regulations on drinking water and industrial discharge. One effective strategy against this is adsorptive removal, in which a suitably functionalized porous material is added to water treatment protocols. Thiol (SH) group-grafted structures perform commendably; however, insufficient attention is paid to the cost, scalability, and reusability or how the arrangement of sulfur atoms could affect the HgII binding strength. We used an inexpensive and scalable porous covalent organic polymer (COP-130) to systematically introduce thiol functional groups with precise chain lengths and sulfur content. Thiol-functionalized COP-130 demonstrates enhanced wettability and excellent HgII uptake of up to 936 mg g−1, with fast kinetics and exceptionally high selectivity. These Hg adsorbents are easily regenerated with HCl and can be used at least six times without loss of capacity even after treatment with strong acid, a rare performance in the domain of Hg-removal research. 相似文献
2.
Nonlinear Dynamics - This paper considers the distributed adaptive neural consensus tracking control problem for a class of uncertain nonaffine nonlinear multi-agent systems. By making use of the... 相似文献
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Sung Hwan Koo Dong Jun Li Taeyeong Yun Dong Sung Choi Kyung Eun Lee Gil Yong Lee Youngtak Oh Joonwon Lim Suchithra Padmajan Sasikala Ho Jin Lee In Ho Kim Hong Ju Jung Rishabh Jain Sang Ouk Kim 《Particle & Particle Systems Characterization》2019,36(7)
Efficient water electrolysis catalyst is highly demanded for the production of hydrogen as a sustainable energy fuel. It is reported that cobalt derived nanoparticle (CoS2, CoP, CoS|P) decorated reduced graphene oxide (rGO) composite aerogel catalysts for highly active and reliable hydrogen evolution reaction electrocatalysts. 7 nm level cobalt derived nanoparticles are synthesized over graphene aerogel surfaces with excellent surface coverage and maximal expose of active sites. CoS|P/rGO hybrid aerogel composites show an excellent catalytic activity with overpotential of ≈169 mV at a current density of ≈10 mA cm?2. Accordingly, efficient charge transfer is attained with Tafel slope of ≈52 mV dec?1 and a charge transfer resistance (Rct) of ≈12 Ω. This work suggests a viable route toward ultrasmall, uniform nanoparticles decorated graphene surfaces with well‐controlled chemical compositions, which can be generally useful for various applications commonly requiring large exposure of active surface area as well as robust interparticle charger transfer. 相似文献
6.
Indermeet Kohli Taylor L. Braunberger Amanda F. Nahhas Fatima N. Mirza Mohsen Mokhtari Alexis B. Lyons Nikiforos Kollias Eduardo Ruvolo Henry W. Lim Iltefat H. Hamzavi 《Photochemistry and photobiology》2020,96(1):208-214
Human skin is exposed to visible light (VL; 400–700 nm) and long-wavelength ultraviolet A1 (UVA1) radiation (370–400 nm) after the application of organic broad-spectrum sunscreens. The biologic effects of these wavelengths have been demonstrated; however, a dose–response has not been investigated. Ten subjects with Fitzpatrick skin phototype IV-VI were enrolled. Subjects were irradiated with 2 light sources (80–480 J cm−2): one comprising VL with less than 0.5% UVA1 (VL+UVA1) and the other pure VL. Skin responses were evaluated for 2 weeks using clinical and spectroscopic assessments. 4-mm punch biopsies were obtained from nonirradiated skin and sites irradiated with 480 J cm−2 of VL+UVA1 and pure VL 24 h after irradiation. Clinical and spectroscopic assessments demonstrated a robust response at VL+UVA1 sites compared with pure VL. Histology findings demonstrated a statistically significant increase in the marker of inflammation (P < 0.05) and proliferation (P < 0.05) at the irradiated sites compared with nonirradiated control. Threshold doses of VL+UVA1 resulting in biologic responses were calculated. Results indicate that approximately 2 h of sun exposure, which equates to VL+UVA1 dose (~400 J cm−2), is capable of inducing inflammation, immediate erythema and delayed tanning. These findings reinforce the need of photoprotection beyond the UV range. 相似文献
7.
Nikolaus Nestle Zi Jian Lim Tobias Böhringer Sarah Abtmeyer Sven Arenz Felix C. Leinweber Thomas Weiß Erik von Harbou 《Magnetic resonance in chemistry : MRC》2020,58(12):1213-1221
The considerations for use of compact nuclear magnetic resonance in a large-scale industrial environment clearly differ from those in academic and educational settings and even from those in smaller companies. In the first part of this article, these differences will be discussed along with the additional requirements that need to be fulfilled for successful applicability in different use cases. In the second part of the article, outcomes from different research activities aiming to fulfill these requirements will be presented with a focus on an online reaction-monitoring study on a lab-scale nucleophilic chlorination reaction. 相似文献
8.
Dr. Joohyun Lim Ghoncheh Kasiri Dr. Rajib Sahu Kevin Schweinar Dr. Katharina Hengge Prof. Dr. Dierk Raabe Prof. Dr. Fabio La Mantia Prof. Dr. Christina Scheu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(22):4917-4922
The structural changes of copper hexacyanoferrate (CuHCF), a Prussian blue analogue, which occur when used as a cathode in an aqueous Zn-ion battery, are investigated using electron microscopy techniques. The evolution of ZnxCu1−xHCF phases possessing wire and cubic morphologies from initial CuHCF nanoparticles are monitored after hundreds of cycles. Irreversible introduction of Zn ions to CuHCF is revealed locally using scanning transmission electron microscopy. A substitution mechanism is proposed to explain the increasing Zn content within the cathode material while simultaneously the Cu content is lowered during Zn-ion battery cycling. The present study demonstrates that the irreversible introduction of Zn ions is responsible for the decreasing Zn ion capacity of the CuHCF cathode in high electrolyte concentration. 相似文献
9.
Dr. Gao Li Wu-Yue Yang Wen-Hao Li Yun-Yi Luo Yeh-Jun Lim Prof. Dr. Yang Li Dr. Ashim Paul Prof. Dr. Daniel Segal Liu Hong Prof. Dr. Yan-Mei Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(16):3499-3503
It has been reported that many molecules could inhibit the aggregation of Aβ (amyloid-β) through suppressing either primary nucleation, secondary nucleation, or elongation processes. In order to suppress multiple pathways of Aβ aggregation, we screened 23 small molecules and found two types of inhibitors with different inhibiting mechanisms based on chemical kinetics analysis. Trp-glucose conjugates ( AS2 ) could bind with fibril ends while natural products ( D3 and D4 ) could associate with monomers. A cocktail of these two kinds of molecules achieved co-inhibition of various fibrillar species and avoid unwanted interference. 相似文献
10.
K.C. Devarayapalli S.V. Prabhakar Vattikuti T.V.M. Sreekanth Ki Soo Yoo P.C. Nagajyothi Jaesool Shim 《应用有机金属化学》2020,34(3):e5376
Herein, cobalt (Co)-based metal–organic zeolitic imidazole frameworks (ZIF-67) coupled with g-C3N4 nanosheets synthesized via a simple microwave irradiation method. SEM, TEM and HR-TEM results showed that ZIF-67 were uniformly dispersed on g-C3N4 surfaces and had a rhombic dodecahedron shape. The photocatalytic properties of g-C3N4/ZIF-67 nanocomposite were evaluated by photocatalytic dye degradation of crystal violet (CV), 4-chlorophenol (4-CP) and photocatalytic hydrogen (H2) production. In presence of visible light illumination, the photocatalytic dye results showed that 95% CV degradation and 53% 4-CP degradation within 80 min. The H2 production of the g-C3N4/ZIF-67 composite was 2084 μmol g−1, which is 3.84 folds greater than that of bare g-C3N4 (541 μmol g−1). 相似文献