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A protocol for the chemically divergent synthesis of β-lactams and α-amino acid derivatives with isothiourea (ITU) catalysis by switching solvents was developed. The stereospecific Mannich reaction occurring between imine and C(1)-ammonium enolate generated zwitterionic intermediates, which underwent intramolecular lactamization and afforded β-lactam derivatives when DCM and CH

A metal-free amino-heteroarylation of unactivated olefins via new organic photoredox catalysis was reported, providing a concise and efficient approach for the rapid synthesis of various δ (β, ε)-amino ketones under mild conditions. A series of mechanistic experiments and DFT calculations indicate that this transformation undergoes a photoredox catalytic sequential radical addition/functional group migration process.

Organophotoredox catalytic four-component radical-polar crossover cascade reactions for the stereoselective synthesis of β-amido sulfones with high atom-, step-, and redox economy and excellent diastereoselectivity.

We have developed a metal-free, visible-light driven chiral phosphoric acid catalyzed asymmetric intermolecular, three-component radical-initiated dicarbofunctionalization and oxytrifluoromethylation of enamines.

Nickel-metal hydride (Ni-MH) batteries were widely used due to their various advantages, but its further application and development have been seriously hindered by the low electrochemical discharge capacity of conventional hydrogen storage alloy electrode. The hydrogenated amorphous silicon (a-Si:H) thin film electrode for Ni-MH battery has been proven to have a dramatic electrochemical capacity. We prepared a-Si:H thin films by a two-step process of rf-sputtering followed by hydrogenation, and investigated the effect of hydrogenation on the structure and electrochemical properties of which as an anode. The maximum discharge capacity of a-Si:H thin film electrode after hydrogenation increases from initial 180 mAh·g−1to 1827 mAh·g−1, which is over tenfold that of as-deposited hydrogen-less a-Si thin film electrode. Then, the preliminary relationships between hydrogen content and electrochemical performance of a-Si:H thin film electrode were analyzed, and several negative factors of electrochemical performance for a-Si:H thin film electrode were proposed.

Background Diabetes mellitus (DM) is a major risk factor for tuberculosis (TB). Evidence has linked the DM-related dysbiosis of gut microbiota to modifiable host immunity to Mycobacterium tuberculosis infection. However, the crosslinks between gut microbiota composition and immunological effects on the development of latent TB infection (LTBI) in DM patients remain uncertain. Methods We prospectively obtained stool, blood, and medical records from 130 patients with poorly-controlled DM (pDM), defined as ever having an HbA1c > 9.0% within previous 1 year. Among them, 43 had LTBI, as determined by QuantiFERON-TB Gold in-Tube assay. The differences in the taxonomic diversity of gut microbiota between LTBI and non-LTBI groups were investigated using 16S ribosomal RNA sequencing, and a predictive algorithm was established using a random forest model. Serum cytokine levels were measured to determine their correlations with gut microbiota. Results Compared with non-LTBI group, the microbiota in LTBI group displayed a similar alpha-diversity but different beta-diversity, featuring decrease of Prevotella_9, Streptococcus, and Actinomyces and increase of Bacteroides, Alistipes, and Blautia at the genus level. The accuracy was 0.872 for the LTBI prediction model using the aforementioned 6 microbiome-based biomarkers. Compared with the non-LTBI group, the LTBI group had a significantly lower serum levels of IL-17F (p = 0.025) and TNF-α (p = 0.038), which were correlated with the abundance of the aforementioned 6 taxa. Conclusions The study results suggest that gut microbiome composition may modulate host immunity relevant to TB susceptibility, and microbial signature might be a potential diagnostic biomarker and therapeutic target for LTBI in pDM patients.

A green and practical divergent Ritter-type amination via a photoredox catalytic four-component radical-polar crossover process was developed. This versatile protocol presents a modular and powerful strategy to access functionalized β-sulfonyl imides and imines under mild conditions from readily available and stable substrates with high atom-, step- and redox economy. We manipulated carboxylic acids and benzotriazoles to precisely attack the nitrilium ion instead of the carbocation, thus preventing many complicated side reactions of the photocatalytic reactions. Furthermore, the synthetic utility of this divergent Ritter reaction is further demonstrated by the late-stage modification of pharmaceutical and natural product derivatives.

A Sc(OTf)3 catalyzed [3 + 2]-annulation reaction between donor–acceptor aziridines and several exo-glycals has been developed. Using this method, some exo-glycals derived from D-ribose, D-galactose and uridine can be converted into carbohydrate-spiro-heterocycles easily in good yields. Simple derivatization of the products gives proline analogues and polycyclic compounds. Moreover, this reaction disclosed the stereochemistry characteristic of the reaction between racemic D–A aziridines and chiral enolethers.

A photocatalytic tandem cyclization of o-alkenylbenzaldehydes using pyridinium salts as the amination reagent is described. A variety of valuable seven-membered nitrogenous heterocyclic skeletons are prepared in modest to excellent yields in concise one-step. This transformation features mild reaction conditions and exceptional functional group tolerance. In addition, combining control experiments and density functional theory (DFT) calculations on the mechanism can explain the reaction selectivity.

Using diverse carbon-centered radical precursors and electron-rich (hetero)aromatics and alcohols as nucleophiles, a visible-light driven chiral phosphoric acid (CPA) catalyzed asymmetric intermolecular, three-component radical-initiated dicarbofunctionalization and oxytrifluoromethylation of enamines was developed, which provides a straightforward access to chiral arylmethylamines, aza-hemiacetals and γ-amino acid derivatives with excellent enantioselectivity. As far as we know, this is the first example of constructing a chiral C-O bond using simple alcohols

The influences of Gd and Co co-substitution for La and Ni on phase structures, and electrochemical properties of La0.83-xGdxMg0.17Ni3.35-2xCo2xAl0.15 (x = 0-0.83) alloys were investigated. All the alloys contained A2B7-type (Ce2Ni7- and Gd2Co7-type) phase, Pr5Co19-type phase, PuNi3-type phase and CaCu5-type phase. The partial replacement of Gd and Co for La and Ni increased the phase abundance of the Ce2Ni7-type superstructure and decreased cell volumes, which contributed to a better hydrogen absorption capacity, cyclic stability and HRD. Compared to those of single Gd- or Co-substitutions, the synergistic effects of Gd and Co on the overall electrochemical properties of alloys were significant. Such a superior overall electrochemical performance may result from appropriate cell volumes and anti-pulverization abilities.

A synergistic catalytic method combining photoredox catalysis, hydrogen-atom transfer, and proton-reduction catalysis for the dehydrogenative silylation of alkenes was developed. With this approach, a highly concise route to substituted allylsilanes has been achieved under very mild reaction conditions without using oxidants. This transformation features good to excellent yields, operational simplicity, and high atom economy. Based on control experiments, a possible reaction mechanism is proposed.

A promising material for supercapacitors based on 4-methylaniline reduced graphene oxide/polyaniline (GP) composite was successfully prepared through a facile one-pot synthesis route. During the preparation process, 4-methylaniline acted as a reducing agent for graphene oxide (GO) as well as a spacer for the resulting reduced graphene oxide (RGO) sheets. The characterization results reveal that GO was successfully reduced by 4-methylaniline and the RGO sheets covered by polyaniline (PANI) nanowires retain favorable dispersibility in the GP composite. The GP composite shows a high specific capacitance (530.4 F g−1 at 0.5 A g−1) with a good cycling stability (87.61% retention after 3000 cycles). Moreover, the GP composite also delivers a good rate performance of 77.5% retention from 0.5 A g−1 to 20 A g−1, but for the graphene oxide/polyaniline (GOP) composite and pure PANI, the retentions are only 47.2% and 28.9%, respectively.

A novel one-pot triple-reaction strategy for the asymmetric construction of polycyclic skeletons with multiple consecutive chiral centers through aza-Michael/Michael/Wittig/ketyl radical addition/esterification processes is reported. A wide range of polycyclic tetrahydroquinoline derivatives were smoothly obtained from easily available starting materials with good results (up to 80% yield, >20:1 dr, >99% ee) under mild conditions. In this transformation, five chemical bonds and five consecutive chiral centers were successively formed.

Diabetes mellitus (DM) is a major metabolic disorder and an increasing health problem worldwide. Effective non-invasive therapies for DM are still lacking. Here, we have developed Microcurrent electrical nerve stimulation (MENS), a non-invasive therapy, and tested on 46 mice clustered into five groups, such as control, STZ-induced DM, and MENS treatment groups. Experimental results show that MENS treatment is able to improve seven biochemical indexes (e.g., hemoglobin A1c and glucose level). To investigate the mechanisms of MENS treatment on STZ-induced DM, we selected six representative samples to perform microarray experiments for several groups and developed an integrated Hierarchical System Biology Model (HiSBiM) to analyze these omics data. The results indicate that MENS can affect fatty acid metabolism pathways, peroxisome proliferator-activated receptor (PPAR) signaling pathway and cell cycle. Additionally, the DM biochemical indexes and omics data profiles of MENS treatment were found to be consistent. We then compared the therapeutic effects of MENS with anti-diabetic compounds (e.g., quercetin, metformin, and rosiglitazone), using the HiSBiM four-level biological functions and processes of multiple omics data. The results show MENS and these anti-diabetic compounds have similar effect pathways highly correlated to the diabetes processes, such as the PPAR signaling pathway, bile secretion, and insulin signaling pathways. We believe that MENS is an effective and non-invasive therapy for DM and our HiSBiM is an useful method for investigating multiple omics data.

Hookah smoking is becoming increasingly popular worldwide and recent epidemiological studies indicate that it is significantly associated with respiratory diseases, and could contain constituents more harmful than cigarette smoking. However, the gene expression alterations and mechanisms of disease development induced by the hookah constituents are still unclear. Here, we are the first to propose a new experimental design and use RNA sequencing to profile bronchial epithelial cells from different hookah smoking exposure conditions (GSE162386). For our hookah-smoking dataset, we developed an integrated genome-wide model, hierarchical-systems biology model (HiSBiM), to systematically investigate the effects of smoking hookah and to compare the biological pathways with public cigarette smoking datasets. Our results show that the infectious disease-related pathways were enriched in hookah smoking than in cigarette smoking, which could be due to polluted hookah devices or pathogen contaminated water filters. Furthermore, we investigate the subsystem and pathway differences in hookah smoking between charcoal and electronic heating ways. We observed that cardiovascular and atherosclerosis-related pathways were activated after exposure to charcoal combustion, which may relate to combustion components carbon monoxide and polyaromatic hydrocarbons. Overall, our results show that hookah smoking could involve a higher risk in several diseases than cigarette smoking and link the relations between hookah constituents to diseases. We believe that our HiSBiM is a useful integrated method for providing multiple-level valued insights for genome-wide analysis on various omics data sets.

An efficient preparation method for the multisubstituted spiro[4,4]nona-6,8-dienes has been developed via a palladium catalysed [3 + 2]-annulation reaction between vinylcyclopropanes and pentafulvenes. The highlight of this method is the interesting regioselectivity. Furthermore, the products could be converted into more complex polycyclic systems easily.

The correlation between phase structure and electrochemical properties of La0.83Mg0.17Ni3.1Co0.3Al0.1 was investigated firstly by partial substitution of La with Sm. It was found that the La0.83-xSmxMg0.17Ni3.1Co0.3Al0.1 alloy consists mainly of the Ce2Ni7-type phase, the abundance of which reaches the maximum (92.23 wt.%) at x = 0.2 when x is changed from 0 to 0.4. The alloy containing more Ce2Ni7-type phase exhibited the better the cyclic and high rate discharge ability examined by electrochemical measurements, i.e. the best electrochemical performance was confirmed at x = 0.2. Furthermore, the influence of unit cell volumes of the Ce2Ni7-type main phase on electrochemical properties was investigated systematically based on the comparison of substitution effect of Sm, Nd and Y for La at x = 0.2. Compared to those of Nd- and Y-substitutions, the Sm-substituted alloy containing Ce2Ni7-type main-phase showed better overall electrochemical properties, especially Cmax = 393.3 mAh g–1 and S100 = 87.2%. Such superior electrochemical performance may result from appropriate cell volumes and anti-pulverization abilities.

In this paper, we studied the improved flotation behavior of pentlandite by ammoniacal copper(II) solution. The microflotation tests showed that ammoniacal copper(II) solution exhibited better activation effect for the flotation of pentlandite in alkaline pulping (pH 8–11) than CuSO4. Ultraviolet–visible spectroscopy analysis further comfirmed that ammoniacal copper(II) complexes were the dominant species in ammoniacal copper(II) solution, which was responsible for the superior activation effect. Systematic electrochemical studies including cyclic voltammetry (CV) measurements, polarization curves (Tafel plots) and electrochemical impedance spectroscopy (EIS) demonstrated that the electrochemical processes were improved and the hydrophilic hydroxide layers were converted to hydrophobic species on the surfaces of pentlandite in ammoniacal copper(II) solution.

This work develops a photocatalysis method for the synthesis of γ-spirolactams through a tandem intramolecular 1,5-HAT reaction-cyclization process. A variety of novel γ-spirolactams are prepared in good to excellent yields with this method. This transformation features mild reaction conditions and exceptional functional group tolerance. Additionally, γ-terpinene is applied to this transformation as a hydrogen atom donor for the first time.

High electrical conductivity is a crucial factor for improving the electrochemical performance of energy storage materials. In the work, amorphous Ni-C nanoparticles with high electric conductivity are fabricated by mechanical alloying and are used as a novel cathode for supercapacitors. It is shown that the amorphous Ni-C retains a high specific capacitance and remarkable cycling stability after the electrode is activated by chronopotentiometry at 0.5 A g−1, and even more gratifyingly, the rate capability of the material is superior to that of other Ni based materials due to its high electrical conductivity, which is convenient for fast electron transfer in active material and fast reversible Faradic reaction characteristics. Finally, an asymmetric supercapacitor based on Ni-C as the positive electrode and activated carbon as the negative electrode could be cycled reversibly at a high working potential of 0–1.6 V and delivered a high energy density of 39.8 Wh kg−1. These results confirm the significance and tremendous potential of amorphous Ni-C materials for the development of high-performance energy supply systems.

A directing group promoting the cyclopropanation of indoles with 2-furylcarbenoids has been developed. These carbenes are derived from enynones and cost-effective ZnI2 is employed as the catalyst for the efficient construction of various polycyclic compounds under mild reaction conditions.

A C1-symmetric N-heterocyclic carbene (NHC)-catalysed activation of isatin-derived enals under oxidative conditions was achieved. The in situ generated α,β-unsaturated acyl azolium species was efficiently trapped by 1,3-dicarbonyl compounds via a Michael addition/spiroannualtion cascade, delivering a series of synthetically important spirooxindole δ-lactones with up to 96% enantioselectivity.

A 3,4,5-trimethylphenol and Lewis acid dual-catalyzed cascade reaction of donor-acceptor (D-A) cyclopropanes via ring-opening and cyclization is developed. In this reaction, a phenolic compound was used as a covalent catalyst for the first time. Additionally, control experiments proved that 3,4,5-trimethylphenol completed the catalytic cycle by accomplishing the C-C bond cleavage. Using this strategy, a wide variety of substituted naphthalenes has been synthesized from D-A cyclopropanes in moderate to high yields under mild conditions.

This paper studied the effects of graphene oxide (GO) on the slime coatings of serpentine in the flotation of pentlandite. The flotation results showed that the flotation recovery of pentlandite was improved with the addition of GO, compared with carboxymethyl cellulose (CMC). The possible mechanisms of the improved flotation recovery were investigated by electrokinetic study, FTIR study, sedimentation tests and scanning electronic microscopy (SEM) analysis. The experimental results demonstrated that both of the two depressants dispersed the hydrophilic serpentine particles from the pentlandite surface. For GO, however, the flocculation of serpentine was a further reason responsible for the enhanced recovery of pentlandite.

A series of novel biselectrophilic β,γ-unsaturated α-ketoesters were designed and synthesized from rhodanine. Under the catalysis of chiral squaramides, the enantioselective [3 + 3] annulation reaction of these novel ketoesters with pyrazolones was developed. This reaction offers an efficient method for the synthesis of chiral 2'-thioxo-5,6-dihydrospiro[pyrano[2,3

A variety of axially chiral biaryldiols were synthesized in good yields with excellent atropo-enantioselectivities through construction of axially chiral indoles catalyzed by asymmetric hydrogen-bond donors. In addition, the new axially chiral compounds were proved to be efficient and practical catalysts for asymmetric catalysis. The strategy not only provides a novel method to synthesize axially chiral compounds but also extends the scope of chiral catalysts.

On the basis of the Lewis acid-catalyzed Friedel–Crafts alkylation between 1-acyl-2-arylcyclopropanecarboxylate esters and electron-rich phenols, a Sc(OTf)3 catalyzed cascade [4 + 2]-annulation reaction was developed for the direct synthesis of polysubstituted dihydronaphthols from phenols. In this reaction, the structure of products is dominated by the directing effect of the substituent groups on phenols. Meanwhile, a one-pot Friedel–Crafts alkylation/oxidative cyclization reaction was also developed for the synthesis of spiro-fused 2,5-cyclohexadienones.

A novel strategy was developed for the application of Rh carbenes generated from readily accessible N-sulfonyl 1,2,3,-triazoles or diazocompouds in the high order cycloadditions, which offered an efficient route to a variety of N-containing medium-sized rings. The process provided a wide range of cyclohepta[b]pyrazine and cyclohepta[b]pyrrolone derivatives with high yields.

A simple carbonization procedure is proposed for the synthesis of hierarchical nanoporous carbons with controllable pore size and effective surface area as electrode materials for high-performance electrochemical double-layer capacitors. The procedure is based on the carbonization of interpenetrating polymer networks (IPNs) composed of cross-linked polystyrene (PS) and poly(methyl methacrylate) (PMMA). The as-obtained hierarchical nanoporous carbons (HNC-IPNs) have controllable pore size, interconnected pore structure, high specific surface area, excellent electrical conductivity and electrochemical stability with the different mass ratio of PS/PMMA. In addition, there is authentically an excellent linear relationship between effective specific surface area (E-SSA) and specific capacitance. Especially, the HNC-IPN-4 exhibits the highest specific surface area (SSA) of 1346 m2 g−1, relative high E-SSA of 603 m2 g−1, and excellent specific capacitance of 260 F g−1 under the current density of 0.5 A g−1 in 6 M KOH. Meanwhile, the HNC-IPN-4 exhibits a superior cycling performance without any degradation after 10000 cycles with the current density of 2 A g−1 as well as exhibits high capacitance retention, i.e., 96.0% of the initial specific capacitance after 20000 cycles.

Reduced graphene oxide/polyaniline (rGO/PANI) composites are prepared through an effective in situ one-pot synthesis route that includes the reduction of graphene oxide (GO) by aniline under weak alkali condition via hydrothermal method and then followed by in situ polymerization of aniline. X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, ultraviolet-visible spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscope and transmission electron microscope are employed to reveal that GO is successfully reduced by aniline under weak alkali condition and PANI can be deposited on the surfaces of reduced graphene oxide (rGO) sheets. The effect of rGO is optimized by tuning the mass ratios of aniline to GO to improve the electrochemical performance of rGO/PANI composites. The maximum specific capacitance of rGO/PANI composites achieves 524.4 F/g with a mass ratio of aniline to GO 10:1 at a current density of 0.5 A/g, in comparison to the specific capacitance of 397 F/g at the same current density of pure PANI. Particularly, the specific capacity retention rate is 81.1% after 2000 cycles at 100 mv/s scan rate, which is an improvement over that of pure PANI (55.5%).

A Lewis acid catalyzed [3+4]-annulation reaction between cyclopropane 1,1-diesters and anthranils has been developed. This annulation consists of a reaction sequence involving ring-opening/aromatization/nucleophilic addition. Thereinto, aromatization is the driving force for this annulation. Using this reaction, a series of 8-oxa-1-azabicyclo[3.2.1]octanes can be prepared conveniently with excellent diastereoselectivity.

In this work, the MoO2/MoS2 composite material with unique flower-like microsphere structure is prepared via a facile hydrothermal synthesis. Furthermore, the composite material is served as negative electrode for supercapacitors. Ascribe to the synergistic effect, including the improved electron conductivity, the coexistence of two energy storage mechanisms, and a stable flower-like microsphere structure, the as-fabricated MoO2/MoS2 exhibits a high specific capacitance of 433.3 F g−1 at a scan rate of 5 mV s−1 and a superior cycling stability of 84.41% retention after 5000 cycles compared to that of pure MoO2 (33.33% retention after 2000 cycles) and pure MoS2 (58.33% retention after 2000 cycles) at a current density of 1 A g−1 in 1 M Na2SO4 electrolyte. Moreover, we also synthesize a series of MoO2/MoS2 electrode materials, which are used to further illustrate the synergistic effect in MoO2/MoS2 composite materials. This work signifies such materials as negative electrodes exhibit bright application prospects for supercapacitors. Keywords: Molybdenum dioxide, Molybdenum disulfide, Negative electrode, Synergistic effect, Supercapacitors