Hierarchically Designed Three‐Dimensional Macro/Mesoporous Carbon Frameworks for Advanced Electrochemical Capacitance Storage

Mesoporous carbon (m‐C) has potential applications as porous electrodes for electrochemical energy storage, but its applications have been severely limited by the inherent fragility and low electrical conductivity. A rational strategy is presented to construct m‐C into hierarchical porous structures with high flexibility by using a carbon nanotube (CNT) sponge as a three‐dimensional template, and grafting Pt nanoparticles at the m‐C surface. This method involves several controllable steps including solution deposition of a mesoporous silica (m‐SiO₂) layer onto CNTs, chemical vapor deposition of acetylene, and etching of m‐SiO₂, resulting in a CNT@m‐C core–shell or a CNT@m‐C@Pt core–shell hybrid structure after Pt adsorption. The underlying CNT network provides a robust yet flexible support and a high electrical conductivity, whereas the m‐C provides large surface area, and the Pt nanoparticles improves interfacial electron and ion diffusion. Consequently, specific capacitances of 203 and 311 F g^?1 have been achieved in these CNT@m‐C and CNT@m‐C@Pt sponges as supercapacitor electrodes, respectively, which can retain 96 % of original capacitance under large degree compression.     

Azopyridine-imidacloprid derivatives as photoresponsive neonicotinoids

A series of imidacloprid derivatives containing an azopyridine motif as a photoswitchable functional group were designed and synthesized. The new version of photoresponsive imidacloprid analogues showed improved solubility in comparison with their azobenzene analogues. 1.2 to 2-fold activity difference was observed for these azopyridine-imidacloprids against house fly (Musca domestica) and cowpea aphid (Aphis craccivora) upon irradiation.     

钴掺杂MoSe2共生长中氢气的作用分析及磁电特性研究

采用原位共生长化学气相沉积法,以Co3O4、MoO3、Se粉末为前驱物,710℃下在SiO2衬底上生长掺钴MoSe2纳米薄片,分析讨论氢气含量对其生长及调节机理的影响.表面形貌分析表明,氢气的引入促进了成核所需的氧硒金属化合物以及横向生长中需要的CoMoSe化合物分子的生成;AFM(Atomic Force Microscope)结果表明氢气有利于生长单层二维超薄掺钴MoSe2.随着Co3O4前驱物用量的增加,样品的拉曼和PL(Photoluminescence)谱图分别表现出红移和蓝移现象,带隙实现从1.52—1.57 eV的调制.XPS(X-ray photoelectron spectroscopy)结果分析得到Co的元素组分比为4.4%.通过SQUID-VSM(Superconducting QUantum Interference Device)和器件电学测试分析了样品的磁电特性,结果表明Co掺入后MoSe2由抗磁性变为软磁性;背栅FETs器件的阈值电压比纯MoSe2向正向偏移5 V且关态电流更低;为超薄二维材料磁电特性研究及应用拓展提供了基础探索.     

Three-ligand Co-assembled 2D Au(I)-Thiolate Nanosheets

Two-dimensional (2D) Au(I)-thiolate assemblies are a special type of material that can balance high structural stability and rich surface functionality, which shows promising prospects in both fundamental research and applications. Co-assembly of multiple ligands is a facile way to further enrich the surface properties and functions, and expand their application potentials. In this work, taking 3-mercaptopropionic acid (MPA), cysteine (Cys) and 1-thioglycerol (TGO) as example ligands, we studied in detail the possibility to co-assemble them into one nanosheet. Although the three ligands have significantly different controllability and pathways when self-assembling individually with Au(I), they can still be effectively co-assembled by reacting with HAuCl₄ together to obtain three-ligand nanosheets with good colloidal stability. The key points for successful co-assembly are also revealed by comparing single- and three-ligand self-assembly processes, laying a solid foundation for co-assembly of even more ligands. The easy but powerful strategy for 2D materials with closely-packed and multiple tunable surface functional groups addresses the surface engineering problem for 2D materials and paves the way for their wider applications in sensing and biomaterials.     

Prediction of allergic reaction risk of Shenmai injection based on real-world evidence coupled with UPLC–Q-TOF-MS

The allergic reaction (AR) of Chinese herbal injection (CHI) has become one of the most noticeable focuses of public health in China. However, it still remains a considerable controversy as to whether low-molecular-weight components in CHI have potential sensitization. In this study, the relationship between AR and low-molecular-weight component profile of Shenmai injection was explored by an interdisciplinary technology integrating real-world evidence and ultra-performance liquid chromatography–quadrupole time-of-flight mass spectroscopy (UPLC–Q-TOF-MS). The AR information of hospitalized patients was obtained by comprehensively analyzing real-world evidence from January 2015 to June 2019 at two Chinese hospitals. The UPLC–Q-TOF-MS was exploited to systematically investigate the low-molecular-weight component profile with 50–1500 m/z mass range, and 3725 MS1 peaks were detected. The optimized partial least squares discriminant analysis model was established to map the influence of low-molecular-weight components on AR. The results of this study showed that high levels of organic acids administered intravenously might be a potential risk factor for inducing AR. By using this method, Shenmai injection with high AR risk could be recognized precisely with 100% accuracy before clinical use.     

Developing Flexible Quinacridone-Derivatives-Based Photothermal Evaporaters for Solar Steam and Thermoelectric Power Generation

Solar-driven interfacial vaporization by localizing solar-thermal energy conversion to the air−water interface has attracted tremendous attention. In the process of converting solar energy into heat energy, photothermal materials play an essential role. Herein, a flexible solar-thermal material di-cyan substituted 5,12-dibutylquinacridone (DCN−4CQA)@Paper was developed by coating photothermal quinacridone derivatives on the cellulose paper. The DCN−4CQA@Paper combines desired chemical and physical properties, broadband light-absorbing, and shape-conforming abilities that render efficient photothermic vaporization. Notably, synergetic coupling of solar-steam and solar-electricity technologies by integrating DCN−4CQA@Paper and the thermoelectric devices is realized without trade-offs, highlighting the practical consideration toward more impactful solar heat exploitation. Such solar distillation and low-grade heat-to-electricity generation functions can provide potential opportunities for fresh water and electricity supply in off-grid or remote areas.     

Establishment and validation of an SIL-IS LC–MS/MS method for the determination of ibuprofen in human plasma and its pharmacokinetic study

In this work, we developed and validated a highly sensitive, rapid and stable LC–MS/MS method for the determination of ibuprofen in human plasma with ibuprofen-d3 as a stable isotopically labeled internal standard (SIL-IS). Human plasma samples were prepared by one-step protein precipitation. The chromatographic separation was achieved on a Poroshell 120 EC-C₁₈ (2.1 × 50 mm, 2.7 μm). Aqueous solution (containing 0.05% acetic acid and 5 mm NH₄Ac) and methanol were selected as the mobile phase with gradient elution. An electrospray ionization source was applied and operated in negative ion mode. Multiple reaction monitoring mode was used for quantification using target fragment ions m/z 205.0 → 161.1 for ibuprofen and m/z 208.0 → 164.0 for SIL-IS, respectively. This method exhibited a linear range of 0.05–36 μg/ml for ibuprofen with correlation coefficient >0.99. Mean recoveries of ibuprofen in human plasma ranged from 78.4 to 80.9%. The RSD of intra- and inter-day precision were both < 5%. The accuracy was between 88.2 and 103.67%. The matrix effect was negligible in human plasma, including lipidemia and hemolytic plasma. A simple, efficient and accurate LC–MS/MS method was successfully established and applied to a pharmacokinetic study in healthy Chinese volunteers after a single oral administration of ibuprofen granules.     

Nonlocal Galerkin Strip Transfer Function Method for Vibration of Double-Layered Graphene Mass Sensor

Double-layered graphene sheets(DLGSs) can be applied to the development of a new generation of nanomechanical sensors due to their unique physical properties. A rectangular DLGS with a nanoparticle randomly located in the upper sheet is modeled as two nonlocal Kirchhoff plates connected by van der Waals forces. The Galerkin strip transfer function method which is a semi-analytical method is developed to compute the natural frequencies of the massplate vibrating system. It can give exact closed-form solutions along the longitudinal direction of the strip. The results obtained from the semi-analytical method are compared with the previous ones, and the differences between the single-layered graphene sheet(SLGS) and the DLGS mass sensors are also investigated. The results demonstrate the similarity of the in-phase mode between the SLGS and DLGS mass sensors. The sensitivity of the DLGS mass sensor can be increased by decreasing the nonlocal parameter, moving the attached nanoparticle closer to the DLGS center and making the DLGS smaller. These conclusions are helpful for the design and application of graphene-sheet-based resonators as nano-mass sensors.     

Electrophilic fluoroalkylthiolation induced diastereoselective and stereospecific 1,2-metalate migration of alkenylboronate complexes

A transition metal free process for conjunctive functionalization of alkenylboron ate-complexes with electrophilic fluoroalkylthiolating reagents is described, affording β-trifluoroalkylthiolated and difluoroalkylthiolated boronic esters in good yield and excellent diastereoselectivity. The potential applicability of the method was demonstrated by the preparation of a difluoromethylthiolated mimic 12 of a potential drug molecule PF-4191834 for the treatment of asthma.

A transition metal free process for conjunctive functionalization of alkenylboron ate-complexes with electrophilic fluoroalkylthiolating reagents affords β-tri- and difluoroalkylthiolated boronic esters in good yield and diastereoselectivity.

An electrophile-induced 1,2-metalate migration of an alkenylboron “ate” complex and subsequent base-promoted β-elimination to form a functionalized cis-alkene, now the so-called Zweifel reaction, was first reported by Zweifel and co-workers in 1967 (Fig. 1A).^1–3 The reaction was proposed to proceed via an initial attack of the π electron of the alkene moiety to iodine to generate a zwitterionic iodonium ion, which then undergoes a stereospecific 1,2-metalate to afford a β-iodoboronic ester, followed by anti-elimination upon treatment with a base to afford a cis-olefin. Thus, if the iodine is replaced by an alternative electrophilic reagent and the use of a base is omitted, an interrupted-Zweifel reaction for the preparation of a stereospecific β-functionalized boronic ester could be realized. Toward this end, Aggarwal reported the first example of such a reaction by employing PhSeCl as the electrophilic reagent.⁴ It was proposed that PhSeCl first reacts with an alkenylboronate complex to form a zwitterionic seleniranium ion. Subsequent diastereospecific 1,2-metalate migration affords the stereospecific β-seleno-alkylboronate (Fig. 1B). Likewise, shortly after, Denmark and co-workers reported an analogous Lewis-base catalysed enantioselective and diastereoselective carbosulfenylation of an alkenylboronate complex using N-arylthiosaccharin as the electrophile (Fig. 1C).⁵Open in a separate windowFig. 1The interrupted Zweifel reaction.In light of these discoveries and our recent success in the development of a toolbox of electrophilic fluoroalkylthiolating reagents including three trifluoromethylthiolating reagents α-cumyltrifluoromethane sulfenate,⁶N-trifluoromethylthio-saccharin⁷ and N-trifluoromethylthiodibenzenesulfonimide,⁸ and two difluoromethylthiolating reagents N-difluoromethylthiophthalimide⁹ and S-(difluoromethyl)benzenesulfonothioate,¹⁰ we wondered whether these electrophilic fluoroalkylthiolating reagents could also trigger the proposed stereospecific 1,2-metalatation of the alkenylboronate complex to afford β-fluoroalkylthiolated borane derivatives (Fig. 1D). The trifluoromethylthio (–SCF₃) and the difluoromethylthio (–SCF₂H) groups have gained great attention recently, partially because of their high and tuneable lipophilicity¹¹ that might improve the drug candidate''s cell membrane permeability and consequently, its overall pharmacokinetics.¹² Thus, the development of new efficient reactions for the incorporation of the trifluoromethylthio¹³ or difluoromethylthio groups¹⁴ would be of vital importance in facilitating medicinal chemists'' endeavours in new drug discovery. Herein, we report that by employing electrophilic difluoromethylthiolating reagent PhSO₂SCF₂H 2a as the electrophile, the proposed difluoromethylthiolating induced stereospecific 1,2-metalate migration of alkenyl boronate complexes occurred smoothly to afford β-difluoromethylthiolated boronic esters in good yields and excellent diastereoselectivity. Likewise, when electrophilic trifluoromethylthiolating reagent N-trifluoromethylthiosaccharin 7 was used, an analogous reaction for the diastereoselective formation of β-trifluoromethylthiolated boronic esters was successfully achieved.We began our study by examining the reaction of the electrophilic difluoromethylthiolating reagent 2a with the alkenylboronate complex which was generated in situ by mixing 1a and PhLi in diethyl ether. It was found that the reaction in CH₃CN occurred in full conversion after 12 hours at room temperature, affording the corresponding product 3a in 53% yield (Table 1, entry 1). When the amount of PhLi was increased to 1.3 equivalents, the yield was increased to 76%, while the yield decreased to 66% when 2.0 equivalents of PhLi were used, likely due to the decomposition of the product under strong basic conditions (Table 1, entries 1–5). We then further investigated the effect of the reaction temperature and the solvent. It was found that the temperature did not affect the reaction significantly since the yields of the desired products were decreased slightly to 72% and 70%, respectively, when the reactions were conducted at 0 °C or −15 °C (Table 1, entries 6 and 7). Likewise, the reaction was not sensitive to the polarity of the solvent since reactions conducted in less polar solvents such as THF or CH₂Cl₂ or nonpolar solvents like toluene occurred in slightly lower 60–73% yields (Table 1, entries 9–11). We also found that reaction using N-difluoromethylthiophthalimide as the electrophilic difluoromethylthiolating reagent gave the same product in a slightly lower yield (Table 1, entry 8).Optimization of conditions for the reaction of the alkenyl boronate complex with PhSO₂SCF₂H^a