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PurposeDrawing on the dynamic managerial capability perspective and the dynamic capability perspective of business model (BM) literature, this paper aims to investigate how top management team internal social capital (TISC) promotes BM design and how such effects are moderated by market dynamics (i.e. demand uncertainty and competitive intensity).Design/methodology/approachThe proposed hypotheses were tested by a questionnaire-based survey. The empirical study was conducted on a sample of 210 firms in China. The model was tested via hierarchical regression analysis.FindingsTISC has a positive effect on BM efficiency but an inverted U-shaped effect on BM novelty. The effects of TISC on BM efficiency and novelty are contingent on demand uncertainty and competitive intensity in different ways. Specifically, this study finds that demand uncertainty strengthens the inverted U-shaped effect of TISC on BM novelty. This study also finds that competitive intensity strengthens the positive effect of TISC on BM efficiency but weakens the inverted U-shaped effect of TISC on BM novelty.Originality/valueThe conclusion contributes to the dynamic capability perspective of BM literature in two ways. First, it offers a dynamic managerial capability perspective for understanding the antecedents of BM design. It highlights TISC, a root of dynamic managerial capability, as an important internal antecedent of BM design. Second, it provides a more nuanced understanding of the role of TISC in BM design. The findings show the distinct effects of TISC on BM efficiency and novelty. This study also discusses the contingency role market dynamics play in the TISC–BM design relationship.

To clarify the role of long intergenic nonprotein-coding RNA 1232 (LINC01232) in the progression of gastric cancer and the potential mechanism, we analyzed the expression of LINC01232 in TCGA database using the GEPIA online tool, and the LINC01232 level in gastric cancer cell lines was detected by quantitative real time-polymerase chain reaction (qRT-PCR) as well. Cell proliferation assay, colony formation assay, transwell assay and tumor formation experiment in nude mice were conducted to observe the biological behavior changes of gastric cancer cells through the influence of LINC01232 knockdown. LncATLAS database and subcellular isolation assay were used for subcellular distribution of LINC01232 in gastric cancer cells. The interaction among LINC01232, zeste homolog 2 (EZH2) and kruppel-like factor 2 (KLF2) was clarified by RNA-protein interaction prediction (RPISeq), RNA immunoprecipitation (RIP), qRT-PCR and chromatin immunoprecipitation (ChIP) assay. Rescue experiments were further conducted to elucidate the biological function of LINC01232/KLF2 axis in the progression of gastric cancer. LINC01232 was upregulated in stomach adenocarcinoma (STAD) tissues and gastric cancer lines. LINC01232 knockdown inhibited the proliferative capacities of gastric cancer cells in vitro, and impaired in vivo tumorigenicity. LINC01232 was mainly distributed in the cell nucleus where it epigenetically repressed KLF2 expression via binding to the enhancer of EZH2, which was capable of binding to promoter regions of KLF2 to induce histone H3 lysine 27 trimethylation (H3K27me3). LINC01232 exerts oncogenic activities in gastric cancer via inhibition of KLF2, and therefore, the knockdown of KLF2 could reverse the regulatory effect of LINC01232 in the proliferative ability of gastric cancer cells.

Global climate change, continuous economic development and accelerated urbanization have increased the frequency and complexity of various incidents. Risk assessment is an important means to deal with different crises and incidents. Based on the systematic analysis of the basic connotation, attribute relationship and main contents of risk assessment, this study extends the traditional two-dimensional risk matrix to multi-dimensional risk matrix. On this basis, this study further proposes four comprehensive risk assessment methods, including total ordinal, weighted average, Euclidean distance and two-norm methods. Empirical research was conducted by selecting three types of natural disasters, regional agro-meteorological disasters, geological disasters and forest fires, in 30 related regions in China between 2010 and 2019. The results indicated that compared to the two-dimensional risk matrix, the multi-dimensional risk matrix can intuitively characterise and compare the all-round risk situation of different regions, periods, types and dimensions, which is more helpful for a systematic analysis and risk comparison. All four evaluation methods proposed in this paper proved able to effectively conduct comprehensive regional risk evaluations with consistent results. However, when considering the fitting coefficient between the results obtained by various evaluation methods and the comprehensive evaluation results, it can be found that the accuracy (i.e. fitting coefficient) of Euclidean distance method is significantly higher than that of the other three methods. In the last 10 years, the temporal order of natural disaster risk in China has been more volatile, with Beijing, Shanxi, Tianjin, Hebei, Liaoning, Ningxia, Zhejiang, Shaanxi, Fujian and Gansu experiencing higher volatility in the ranking of natural disaster risk.

To find ideal hydrogen storage media, hydrogen storage performance of Li decorated net-τ has been investigated by first-principles calculations. Maximum 6 Li atoms are adsorbed on net-τ, with the average binding energy of 2.15 eV for per Li atom. Based on 6Li-decorated net-τ, up to twenty H2 molecules are adsorbed, with a high H2 storage capacity of 12.52 wt% and an appropriate adsorption energy of 0.21 eV/H2. Finally, H2 uptake performance is measured by GCMC simulations. Our results suggest that Li-decorated net-τ may be a promising hydrogen storage medium under realistic conditions.

To obtain high hydrogen storage performance, Li and Na co-decorated T4,4,4-graphyne have been studied by the method of first-principles calculations in this paper. Li and Na atoms are bound on hexagonal ring and acetylenic ring included in T4,4,4-graphyne, with the average adsorption energy of 1.73 and 2.38 eV, respectively. Our calculations show that the maximum gravimetric density of H2 uptake is 10.46 wt%, and an appropriate adsorption energy is reached. Moreover, by plotting charge density differences, it is found that the induced electric field between Li/Na and T4,4,4-graphyne can enhance the adsorption for hydrogen molecule. Furthermore, this complex is thermodynamic stable at room temperature, which is certificated by molecule dynamics simulation. Our results demonstrate that Li and Na co-decorated T4,4,4-graphyne is an alternative material for hydrogen storage.

In this paper, the hydrogen storage performance of Sc (Ti, Li)-modified [Formula: see text]-graphene ([Formula: see text]-g) is investigated by density functional theory (DFT). Sc and Ti can be stably adsorbed on [Formula: see text]-g with the binding energies of 4.78 eV and 4.83 eV, respectively. Li atoms can also be stably absorbed on B-doped [Formula: see text]-g with the binding energy of 2.51 eV. In addition, Sc and Ti atoms attached on [Formula: see text]-g can adsorb up to ten and eight hydrogen molecules, and the hydrogen gravimetric storage capacity reaches 7.93 wt.% and 6.20 wt.%, respectively. Li atoms attached on B-doped [Formula: see text]-g can adsorb up to eight hydrogen molecules with the hydrogen gravimetric storage capacity 9.32 wt.%, all meeting DOE standards. On the whole, Bader charge analysis shows that the charge is transferred from C atoms to H atoms, which is more conducive to hydrogen adsorption. All the researches prove that the Sc, Ti-decorated [Formula: see text]-g and Li-decorated B-doped [Formula: see text]-g are potential hydrogen storage materials.

Background Working memory deficits are one of the core and most characteristic clinical features of cognitive impairment in schizophrenia. Cognitive training can improve the cognitive function of patients with schizophrenia. However, the overall and transfer effects of working memory treatment (WMT) require improvement. Numerous studies have confirmed that transcranial direct current stimulation (tDCS) enhances neuroplasticity in the brain, providing a new treatment approach for cognitive impairment in patients with schizophrenia. We hypothesize that a training mode combining “preheating” (tDCS, which changes the neural activity of working memory-related brain regions) and “ironing” (WMT) affords greater cognitive improvements than WMT alone. In addition, this study aims to examine the mechanisms underlying the superiority of tDCS combined with WMT in improving cognitive function in patients with schizophrenia. Methods This study will include 120 patients with schizophrenia aged 18–60 years. The patients will be randomized into four groups: the study group (tDCS + WMT), tDCS group (tDCS + simple response training, SRT), WMT group (sham tDCS + WMT), and control group (sham tDCS + SRT). Patients will receive 20-min, 2 mA sessions of active or sham tDCS twice a day on weekdays for 2 weeks. Each stimulation will be immediately followed by a 1 − 2-min rest and 40 min of WMT or SRT. The primary outcome is cognitive function, measured using Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and some subscales of the MATRICS Consensus Cognitive Battery (MCCB). The secondary outcomes are other behavioral measures, variations in brain imaging, and serum levels of brain-derived neurotrophic factor (BDNF). All outcomes will be measured at baseline, post-treatment, and 3-month follow-up, except for brain imaging and BDNF levels, which will be measured at baseline and post-treatment only. Discussion If tDCS combined with WMT results in significant improvements and prolonged effects on working memory, this method could be considered as a first-line clinical treatment for schizophrenia. Moreover, these results could provide evidence-based support for the development of other approaches to improve cognitive function in patients with schizophrenia, especially by enhancing WMT effects. Trial registration Chictr.org.cn; ChiCTR2200063844. Registered on September 19, 2022.

This study explores the core genes involved in the pathogenesis of ACTH-independent macronodular adrenal hyperplasia (AIMAH), so as to provide robust biomarkers for the clinical diagnosis and treatment of this disease. Gene Expression Omnibus (GEO) database was used to obtain GSE25031 microarray dataset. R package “limma” was applied to identify differentially expressed genes (DEGs) between AIMAH and normal samples. The Database for Annotation, Visualization and Integrated Discovery (DAVID) was employed to perform Gene Ontology (GO) annotation for the DEGs, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis was conducted. A protein-protein interaction network (PPI) was constructed using the STRING online website and visualized using the Cytoscape software. The key modules and hub genes were then identified. Finally, Gene Set Enrichment Analysis (GSEA) enrichment analysis was carried out to find the signaling pathways of significant clinical value in AIMAH. A total of 295 DEGs between AIMAH and healthy samples were screened out, including 164 upregulated genes and 131 downregulated genes. Combining enrichment analysis and PPI network construction, there were 5 signifiant pathways and 10 hub genes, among which 3 genes (FOS, FOSB, and DUSP1) were identified as potential core genes of clinical significance in AIMAH. In conclusion, the 3 core genes, FOS, FOSB, and DUSP1, identified here might be potential biomarkers for AIMAH, and the current study is of guiding significance for clinical diagnosis and treatment of this disease.

Prior studies that examine business model innovations lack consideration on how value propositions are best developed in specific contexts or how restructuring other components can deliver on value propositions. This article first identifies three types of Chinese consumption behaviors—imitation-based “good-enough” consumption, renqing consumption, and face consumption—and their corresponding value propositions based on value-hierarchy theory. We then look at Chinese companies that illustrate how business model innovations that focus on the targeted value propositions are initiated, formulated, and implemented. In particular, we identify four types of business model innovations: imitation-based “good-enough” business models, renqing business models, face business models, and hybrid business models. We conclude with practical implications for conducting and implementing business model innovations in China.

A new-type 3D pillared graphene framework with hybrid fullerene and nanotube pillars (PGF-hFN) has been created depended on density functional theory (DFT) and first-principles molecular dynamics simulations (MD). It is proved to have excellent thermal structural stability. The average adsorption energy of Li is 2.77 eV much higher than the metal cohesive energy excluding lithium aggregation problem. From DFT calculations, for Li-decorated B-doped PGF-hFN, the hydrogen gravimetric density (HGD) is as high as 12.92 wt% and the according volumetric uptake is 96.4 g/L with an average adsorption energy of 0.195 eV per H2. Further grand canonical Monte Carlo (GCMC) simulations predict 7.2 wt% in excess HGD and 53.8 g/L in excess volumetric hydrogen density at near ambient temperature (233 K) and 100 bars with the ideal adsorption enthalpy which have exceeded the 2020 the U.S. Department of Energy (DOE) ultimate target for mobile applications. Our multiscale theoretical simulations indicate this new pillared structure should be a promising carrier accessible for sorption of hydrogen molecules.

Cu2S is considered as one of the potential anode paradigms for advanced rechargeable batteries because of its high theoretical capacity (∼335 mAh·g-1), high and flat charge/discharge voltage plateaus (∼1.7 V vs Li+/Li), stable cycling performance, and its elemental abundance. However, many studies have shown that Cu2S exhibits a dramatic capacity fade in carbonate-based electrolytes, which has precluded its commercialization when paired with high voltage cathodes in state-of-the-art lithium ion batteries. Here, we report on a fundamental mechanistic study of the electrochemical processes of Cu2S in both ether- and carbonate-based electrolytes employing operando synchrotron X-ray methods. Based on our findings, we developed a Cu2S/C composite material that suppresses its failure mechanism in carbonate-based electrolytes and further demonstrated its feasibility in lithium ion full cells for the first time. Our experiment provides the basis for the utilization of Cu2S in industrial-scale applications for large-scale electrical energy storage.

Background Symptomatic intracranial haemorrhage (SICH) is a severe and deadly complication in patients with large vessel occlusion (LVO) who receive endovascular treatment (EVT). Recent studies have indicated that many risk factors, including pretreatment scores and the operation process, may be associated with the occurrence of SICH after thrombectomy. This study aims to identify independent risk factors and establish a novel nomogram-based model for patients with anterior LVO to predict the occurrence of SICH after direct thrombectomy or bridge therapy (thrombectomy based on intravenous thrombolysis). Methods Patients with acute ischaemic stroke after EVT to recanalize the blocked artery in anterior circulation were consecutively recruited from November 2017 to March 2019. Baseline information was collected from each patient. These data were subsequently analysed by R Project for Statistical Computing. Results A total of 127 patients with complete data were classified into the training set, among whom 37 patients (29.1%) fulfilled the criteria for SICH. The results of the multivariate analyses showed that NIHSS (P=0.024), ASPECT (P

Long noncoding RNAs (lncRNAs) display essential roles in cancer progression. FLVCR1-AS1 is a rarely investigated lncRNAs involved in various human cancers, such as hepatocellular carcinoma and lung cancer. However, its function in glioma has not been clarified. In our study, we found that FLVCR1-AS1 was highly expressed in glioma tissues and cell lines. And upregulation of FLVCR1-AS1 predicted poor prognosis in patients with glioma. Moreover, FLVCR1-AS1 knockdown inhibited proliferation, migration and invasion of glioma cells. Through bioinformatics analysis, we identified that FLVCR1-AS1 was a sponge for miR-4731-5p to upregulate E2F2 expression. Moreover, rescue assays indicated that FLVCR1-AS1 modulated E2F2 expression to participate in glioma progression. Altogether, our research demonstrates that the FLVCR1-AS1/miR-4731-5p/E2F2 axis is a novel signaling in glioma and may be a potential target for tumor therapy.

In recent years, with the large increase in the number of motor vehicles in colleges and universities and the lag in campus planning, the relative shortage of parking spaces on campus has become increasingly serious. Taking Baoding College as an example, this article analyzes the current situation of static traffic on campus and finds out the problem of parking on campus through questionnaire surveys and field surveys. Analyze the growth trend of the number of motor vehicles based on the data, use the GM (1, 1) model and the linear fitting model to predict the number of motor vehicles in the future, and determine the size and layout of the parking lot based on the campus size, functional zoning, and road layout. The big campus-based parking system planning method based on big data can effectively solve the problems of small sample data, low accuracy, and poor timeliness of traditional methods, which improves the practicability and scientificity of planning results.

Linear algebra has a very important application in physics and technical disciplines. This article conducted a questionnaire survey on the factors that affect the effect of linear algebra learning; the questionnaire contains several aspects of learning attitude, learning interest, learning methods, teaching methods, etc.; based on recycling data, cross chi-square test and multiple logistic regression analysis are used to obtain the factors that affect the effect of linear algebra learning. The research results show that: learning methods, learning attitudes, teaching methods and elementary algebra basics are the main factors that affect the learning effect of linear algebra; among them, there are positive correlations between teaching methods, learning methods, learning attitudes and learning effects; teaching methods, learning methods 3. The three principal components of learning attitude are positively correlated. Based on the research and analysis, the following conclusions are drawn: finding a suitable learning method for the college students and maintaining a positive learning attitude are effective means to improve the linear algebra learning effect of the college students; in teaching, it is recommended to advance with the times, the teaching content and teaching methods innovate to stimulate students’ interest in learning, thus improving the learning effect of college students’ linear algebra courses.

With the expansion of the scale of our hospital robot laboratory, equipment use, reserves are increasing, manual management equipment information has been unable to adapt to daily management, such as data record error rate increased, the number of experiments increased, equipment loss and maintenance is not clearly defined. In order to ensure the safety and accuracy of the equipment, a system of equipment management systems was developed as a result of the conversion to the use of management systems for the recording and storage of information. The design of this system is a perfect robot laboratory equipment management system based on the development of web framework technology for equipment management functions. The back end of this system uses the Java language, the SSM framework as the main body, the database is built by MySQL relational database, the front-end page uses JSP, Bootstrap, jQuery and other technologies, and uses Eclipse project construction tools for system development. After a period of trial operation, the level of laboratory equipment management has been significantly improved.

In spite of the proliferation of Massive Open Online Courses (MOOCs) in higher education, factors influencing user acceptance of MOOCs are not well understood. This study is intended to inv...

In this study, 38 single nucleotide polymorphism (SNP) markers were developed and characterized in Patelloida pygmaea. The minor allele frequency raged from 0.0833 to 0.5000. The observed heterozygosity varied from 0.0000 to 1.000, and the expected heterozygosity varied from 0.1197 to 0.5496. Polymorphic information content ranged from 0.1103 to 0.4316. The inbreeding coefficient values varied from − 0.3330 to 0.8686. Eleven loci showed significant deviations from the Hardy–Weinberg equilibrium (P

Recently, a novel layered two-dimensional carbon nanomaterial was synthesized named triphenylene-graphdiyne (TpG). The acetylenic ring and triphenylene are included in primitive cell of this structure. In this work, many different strategies have been adopted to investigate hydrogen storage capacity of Li- and Ca-decorated pristine and B-doped TpG by first-principles calculations. The maximum three H2 molecules are captured around every one Li atom by Li-decorated on the acetylenic ring only for TpG. The hydrogen storage gravimetric capacity of 8.17 wt% with an approximate ideal average H2 adsorption energy of 0.18 eV/H2. Moreover, both acetylenic ring and triphenylene are decorated by Li and two H2 molecules are adsorbed for each Li atom. The hydrogen storage capacity reaches to 9.70 wt% with an ideal average hydrogen adsorption energy of 0.27 eV/H2. After two C atoms are doped by B atoms, two more Li atoms are introduced to the triphenylene. Here, maximum 20 H2 molecules are adsorbed on Li-decorated B-doped TpG. The hydrogen storage capacity reaches to 8.77 wt%, with ideal average hydrogen adsorption energy of 0.24 eV/H2. Four H2 molecules can be adsorbed effectively by Ca-decorated pristine TpG with the average hydrogen adsorption energy of 0.19 eV/H2. We also calculated the H2 storage of Ca-decorated B-doped TpG and 5.51 wt% of gravimetric with ideal average hydrogen adsorption energy of 0.25 eV/H2 can be obtained. Our calculation indicates that the Li- and Ca-decorated B-doped TpG and Li-decorated pristine TpG can be a very promising material for reversible hydrogen storage.

Based on density functional theory (DFT) and first-principles molecular dynamics (MD),a new 3D hybrid Boron-Nitride-Carbon–interconnected frameworks (BNCIFs) consisting of organic linkers with Li decoration is created and optimized. Firstly, Li adsorption behaviors on several BNCxcomplexes are investigated and compared systematically. The results indicate C substitution of N atom in pure BN layer could improve the metal binding energy effectively. Secondly, the BNC layer (BNCNN) is chosen to model the frameworks of BNCIFs. The average binding energy of adsorbed Li atoms on BNCIFs is 3.6 eV which is much higher than the cohesive energy of bulk Li and avoids the Li clustering problem. Finally, we study the H2 adsorptions on the Li decorated BNCIFs by DFT. Every Li atom could adsorb four H2 molecules with an average binding energy of 0.24 eV. The corresponding gravimetric and volumetric storage capacities are 14.09 wt% and 126.2 g/L respectively overpassing the published 2020 DOE target. The excellent thermal stability of 160H2@40Li@BNCIFs is also proved by MD. This nanostructure could be served as a promising hydrogen storage medium at ambient conditions.

In this study, 26 single nucleotide polymorphism (SNP) markers were developed and characterized in Nipponacmea schrenckii. The minor allele frequency raged from 0.0238 to 0.3571. The observed heterozygosity and expected heterozygosity ranged from 0.0000 to 0.2381 and from 0.0929 to 0.4866, respectively. Polymorphic information content ranged from 0.0866 to 0.3538. The inbreeding coefficient values varied from − 0.0582 to 0.9985. Four loci showed significant deviations from the Hardy–Weinberg equilibrium (P

Background Overlapping stents represent a new paradigm in endovascular interventions, especially for complex and wide-necked aneurysms. The low-profile visualized intraluminal support (LVIS) device is a new generation of self-expanding braided stents recently introduced in China for stent-assisted coiling of intracranial aneurysms. We report several cases of intracranial aneurysms coiled using overlapping LVIS stents to evaluate its efficacy and safety. Methods Patients with ruptured intracranial aneurysms treated with double LVIS stents at our center between November 2014 and May 2016 were reviewed. The clinical data and technical results are presented. Results Ten patients with 15 aneurysms were treated with double LVIS stents, with a 100% technical success rate. No mortality was observed. Immediate angiographic outcome evaluation showed complete occlusion in 13 aneurysms (86.7%) and neck remnants in 2 aneurysms (13.3%). Conclusions Double LVIS stents are safe and effective in the treatment of intracranial aneurysms, especially complex aneurysms.

Metal sulfides have been drawing more and more attention as electrode materials in batteries due to their high theoretical capacities. However, the volume expansion and loss of active materials are two major problems, hindering further improvement in their electrochemical performances. Herein, a strategy based on physical confinement/chemical adsorption is proposed to fabricate CoS and Co9S8 electrodes for advanced lithium batteries. Via a facile two-step method, porous C/CNT micro/nano-spheres embedding cobalt sulfide nanoparticles are successfully fabricated, in which sulfur is immobilized by C S bonds. Physically, the porous C/CNT micro/nano-spheres well accommodate the volume change and inhibit the loss of active materials. Chemically, the sulfur species are anchored by C S bonds to alleviate the migration and loss. Assembled as lithium battery anodes, the porous cobalt sulfide/carbon composites, particularly the CoS/C/CNT (CoS-0.4C) and Co9S8/C/CNT (Co9S8-0.8C), exhibit superior lithium storage properties to those without any complexing or any C S bonding. Furthermore, an in-situ electrochemical measurement is proposed to detect the existence of Li2S, which is helpful to understand the mechanism of conversion reaction-based metal sulfides.

We describe the complete mitochondrial genome of the important Polyplacophora species, Acanthochitona rubrolineatus. The mitogenome sequence of A. rubrolineatus is 14,988 bp, and all genes show the typical gene arrangement conforming to the Mollusca consensus. The overall base composition of the genome is T 39.0%, C 12.4%, A 31.2% and G 17.4%. The cytochrome c oxidase subunit I (COI) sequence of A. rubrolineatus and other 111 species from Chitonida were used for phylogenetic analysis by Bayesian inference and maximum-likelihood methods. The results show that A. rubrolineatus, Acanthochitona achates, and Acanthochitona defilippi is sister group to three lineages, and both together as the sister group of A. rubrolineata.

Recently developed halide double perovskites ${A}_{2}{M}^{+}{M}^{3+}{X}_{6}$ have attracted attention as potential lead-free perovskite solar cell absorbers. Here, the stability, electronic, and optical properties of the lead-free inorganic-organic hybrid double perovskites ${({\mathrm{CH}}_{3}{\mathrm{NH}}_{3})}_{2}\mathrm{InBi}{X}_{6}$ ($X$ = halogen) are studied based on density functional theory. By investigating the thermodynamic stability against decomposition, the ${({\mathrm{CH}}_{3}{\mathrm{NH}}_{3})}_{2}\mathrm{InBi}{X}_{6}$ double perovskites are shown to be stable. Furthermore, the use of a small magnitude of hydrostatic pressure is proposed to improve the thermodynamic stability of double perovskites ${({\mathrm{CH}}_{3}{\mathrm{NH}}_{3})}_{2}\mathrm{InBi}{X}_{6}$. Meanwhile, the calculated electronic band structures of ${({\mathrm{CH}}_{3}{\mathrm{NH}}_{3})}_{2}\mathrm{InBi}{X}_{6}$ double perovskites exhibit suitable direct band gaps, small carrier effective masses, and three-dimensional electronic dimensionality. This, in turn, leads to strong optical absorption. Both the electronic and optical features make double perovskites ${({\mathrm{CH}}_{3}{\mathrm{NH}}_{3})}_{2}\mathrm{InBi}{X}_{6}$ suitable for applications in optoelectronics.

In this paper, an 11kW wireless charging system based on LCC-SP compensation topology is established, in which a rectifier control with the current doubler is adopted. The impedance characteristics of LCC-SP topology are analyzed. The equivalent impedance of the current doubler is derived by Fourier decomposition of the rectifier current, and then the compensation parameters of LCC-SP are modified according to the derived equivalent circuit. Furtherly, the closed-loop control strategy of the system is proposed by establishing the small-signal model of the current doubler. Simulation and experimental results verified the analysis and validity of the proposed system. Finally, an 11kW wireless charging prototype for electric vehicles is built, and 91.6% efficiency from dc power source to load is achieved.

A three dimensional (3D) dumbbell-like nanostructure composed by interconnected fullerenes and nanotubes with Lithium decoration and boron-doping (37Li@C139B31) has been proposed in virtue of density functional theory (DFT) and first-principles molecular dynamics (MD) simulations which shows excellent geometric and thermal stability. First-principles calculations are performed to investigate the hydrogen adsorption onto the 37Li@C139B31. The results indicate that B substitution can improve the metal binding and the average binding energy of 37 adsorbed Li atoms on the C139B31 (2.79 eV) is higher than the cohesive energy of bulk Li (1.63 eV) suppressing the clustering. Meanwhile, the H2 storage gravimetric density of 178H2@37Li@C139B31 reaches up to 15.9 wt% higher than the year 2020 target from the US department of energy (DOE). The average adsorption energy of H2 molecules falls in a desirable range of 0.18–0.27 eV. Moreover, grand canonical ensemble Monte Carlo (GCMC) simulations reveal that at room temperature the hydrogen gravimetric density (HGD) adsorbed on 37Li@C139B31 reaches up to 11.6 wt% at 100 bars higher than the DOE 2020 target. Our multiscale simulations indicate that our proposed nanostructure provides a promising medium for hydrogen storage.

Cu

Semiconductor-based photocatalysts have received extensive attention for their promising capacity in confronting global energy and environmental issues. In photocatalysis, a large band gap with suitable edge-position is necessary to warrant enough driving force for reaction, whereas a much smaller band gap is needed for visible-light response and high solar energy conversion efficiency. This paradox hinders the development of photocatalysts. Via state-of-the-art first-principles calculations, we find that the transition dipole moments (TDMs) are changed significantly in O-doped partly polymerized g-C3N4, i.e., OH-terminated polymeric heptazine imide (PHI-OH), and concomitantly, an enhancement of visible-light absorption is achieved; meanwhile a large enough band gap can provide a powerful driving force in the photocatalytic watersplitting reaction. Furthermore, by using TDM analysis of the PHI-OH/BC3N heterostructure, direct light excited transition between two building layers can be confirmed, suggesting it as a candidate catalyst for hydrogen evolution. From TDM analysis of the PHI-OH/BCN heterostructure, we also verify a Z-scheme process, which involves simultaneous photoexcitations with strong reducibility and oxidizability. Thus, TDM could be a good referential descriptor for revealing photocatalytic mechanisms in semiconductor photocatalysts and interlayer photoexcitation behavior in layered heterostructures. Hopefully, more strategies via modification of TDMs would be proposed to enhance the visible-light response of a semiconductor without sacrificing its photocatalytic driving force.

With wide application of electric vehicles and large-scale in energy storage systems, the requirement of secondary batteries with higher power density and better safety gets urgent. Owing to the merits of high theoretical capacity, relatively low cost and suitable discharge voltage, much attention has been paid to the transition metal sulfides. Recently, a large amount of research papers have reported about the application of transition metal sulfides in lithium ion batteries. However, the practical application of transition metal sulfides is still impeded by their fast capacity fading and poor rate performance. More well-focused researches should be operated towards the commercialization of transition metal sulfides in lithium ion batteries. In this review, recent development of using transition metal sulfides such as copper sulfides, molybdenum sulfides, cobalt sulfides, and iron sulfides as electrode materials for lithium ion batteries is presented. In addition, the electrochemical reaction mechanisms and synthetic strategy of transition metal sulfides are briefly summarized. The critical issues, challenges, and perspectives providing a further understanding of the associated electrochemical processes are also discussed.

The solution combustion synthesis (SCS) has been widely used to prepare varieties of materials, especially oxides. Nevertheless, there are just a few reports applying the SCS to synthesize sulfides, and most of them are prepared under the protection of an inert atmosphere. As the counterpart of metal oxides, the metal sulfides (MSs) also play an important role in energy-related devices. Herein, a novel air atmospheric SCS is proposed to prepare classes of MSs and the corresponding carbon composites. Thanks to the evaporation and flash burning of ethanol, the O2 is consumed, protecting the MSs and the carbon nanotubes (CNTs) from oxidation; thus, the mesoporous CoS, NiS, Cu2S, and the CoS/CNT, NiS/CNT, Cu2S/CNT, can be easily and rapidly obtained by directly combusting in the air atmosphere. Compared to the conventional SCS for synthesizing the MSs, the equipment requirements of this proposed method are low, which is suitable for large-scale preparation. The lithium storage properties of MSs and MSs/CNTs a...