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In this study, NiGa2O4 ultra-thin nanosheets were synthesized using the LDH template method, and showed excellent gas sensing properties for xylene.

To further determine how BHE affected the growth of HCC cells, the proportion of each cell cycle phase was explored in HCC cells by flow cytometry. Blue honeysuckle (Lonicera caerulea L.) is a species of bush that grows in eastern Russia. Blue honeysuckle extract (BHE) is rich in bioactive phytochemicals which can inhibit the proliferation of tumor cells. The mechanism underlying the anticancer activity of BHE in primary liver cancer is poorly understood. The purpose of this study was to evaluate the growth inhibition mechanism of bioactive substances from blue honeysuckle on hepatocellular carcinoma (HCC) cells and to explore its protein and gene targets. The compounds in BHE were determined by high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS). Cell counting kit-8 (CCK8) assay was used to evaluate the effects of BHE on HCC cell proliferation, and flow cytometry assay (FCA) was used to determine how BHE arrested the proportion of each cell cycle phase in HCC cells. Western blot (WB) was performed to determine the expression of cell cycle-related proteins in HCC cells treated with different concentrations of BHE. The xenograft tumor animal models were established by HCC cell implantation. The results showed that cyanidin-3-o-glucoside and cyanidin-3-o-sophoroside which are the main biologically active components were detected in BHE. BHE is highly effective in inhibiting the proliferation of HCC cells by arresting the HCC cell cycle in the G2/M phase. BHE also downregulated the expression of conventional or classical dendritic cells-2 (cDC2) and cyclin B1 by promoting the expression of myelin transcription factor 1 (MyT1) in HCC cells. The weight and volume of xenografts were significantly decreased in the BHE treated groups when compared to the control group. BHE increased the expression of MyT1 in xenograft tissues. These findings showed that blue honeysuckle extract inhibits proliferation in vivo and in vitro by downregulating the expression of cDC2 and cyclin B1 and upregulating the expression of MyT1 in HCC cells.

Ultrathin indium-doped NiO nanosheets with simultaneously optimized nanostructures and electronic properties were developed to achieve a high response to a low concentration of xylene.

Isotrema pseudohei, a new species from Yunnan, Southwest China, is described and illustrated. It is morphologically similar to I. hei and I. moupinense, but differs from the former in the colour of flower and throat, the size of throat and the shape of gynostemium lobes, and from the latter in the shape of lamina and gynostemium lobes.

Two new steroidal alkaloids, Grandivine A and B (1 and 3), together with eight known related compounds were obtained from the roots of Veratrum grandiflorum Loes. The structures of the compounds were elucidated though extensive spectroscopic techniques. Compounds 3 and 4 exhibited moderate cytotoxic effects against four cancer cell lines.

Although the incidence of adenocarcinoma of the esophagogastric junction (AEG) has been increasing since the past decade, the proportion of AEG cases in two previous clinical trials (ACTS-GC and CLASSIC) that investigated the efficacy of adjuvant chemotherapy was relatively small. Therefore, whether AEG patients can benefit from adjuvant chemotherapy remains unclear.Patients who were diagnosed with pathological stage II/III, Siewert II/III AEG, and underwent curative surgery at three high-volume institutions were assessed. Clinical outcomes were analyzed by using Kaplan-Meier curves, log-rank test, and Cox regression model. Propensity score matching (PSM) was used to reduce the selection bias.A total of 927 patients were included (the chemotherapy group: 696 patients; the surgery-only group: 231 patients). The median follow-up was 39.0 months. The 5-year overall survival was 63.1% (95% confidence interval [CI]: 59.0-67.6%) for the chemotherapy group and 50.2% in the surgery-only group (hazard ratio [HR] = 0.69, 95% CI: 0.54-0.88; p = 0.003). The 5-year, disease-free survival was 35.4% for the chemotherapy group and 16.6% for the surgery-only group (HR = 0.66, 95% CI: 0.53-0.83; p0.001). After PSM, the survival benefit of adjuvant chemotherapy for AEG was maintained. Multivariate analysis for overall survival and disease-free survival further demonstrated the survival benefit of adjuvant chemotherapy, with HRs of 0.63 (p0.001) and 0.52 (p0.001), respectively.Postoperative adjuvant chemotherapy was associated with improved overall survival and disease-free survival in patients with operable stage II or III AEG after D2 gastrectomy.

Tunicosaponins are natural products extracted from Psammosilene tunicoides, which is an important ingredient of Yunnan Baiyao Powder, an ancient and famous Asian herbal medicine. The representative aglycones of tunicosaponins are the oleanane-type triterpenoids of gypsogenin and quillaic acid, which were found to manipulate a broad range of virus-host fusion via wrapping the heptad repeat-2 (HR2) domain prevalent in viral envelopes. However, the unknown biosynthetic pathway and difficulty in chemical synthesis hinder the therapeutic use of tunicosaponins. Here, two novel cytochrome P450-dependent monooxygenases that take part in the biosynthesis of tunicosaponins, CYP716A262 (CYP091) and CYP72A567 (CYP099), were identified from P. tunicoides. In addition, the whole biosynthesis pathway of the tunicosaponin aglycones was reconstituted in yeast by transforming the platform strain BY-bAS with the CYP716A262 and CYP716A567 genes, the resulting strain could produce 146.84 and 314.01 mg/L of gypsogenin and quillaic acid, respectively. This synthetic biology platform for complicated metabolic pathways elucidation and microbial cell factories construction can provide alternative sources of important natural products, helping conserve natural plant resources.

The influence of high concentration Zn2+ on the floatability of sphalerite in an acidic system was investigated via flotation experiments, zeta potential measurements, contact angle measurements, and X-ray photoelectron spectroscopy. The results indicated that Zn2+ was adsorbed on the sphalerite surface and a Zn-hydroxyl complex was formed at a pH of 4 and a Zn2+ concentration of 4×10−2 mol/L. The zeta potential increased and the contact angle decreased from 84.80° to 36.48°, strongly inhibiting the floatability of sphalerite. When S2− or Cu2+ activator was used alone, sphalerite was not activated after Zn2+ was adsorbed, and its contact angle did not change significantly. However, by using a combination of S2− and Cu2+ activators, its floatability was realized after Zn2+ adsorption. This result was attributed to the removal of the Zn-hydroxyl complex on the surface of sphalerite by S2−. After this removal, Cu2+ was adsorbed on the sphalerite surface to form a Cu2S·S0 hydrophobic film.

Reaction between 1,3,5-tris(triazol-1-ylmethyl)-2,4,6-trimethylbenzene (TTTMB), KSCN and Cu(NO3)2·3H2O results in {[Cu3(TTTMB)4 (SCN)6]·3.5H2O}n (1), a special three-dimensional coordination polyme...

The development of cost-effective, high-efficiency bifunctional electrocatalysts as alternatives to the state-of-the-art Pt-based materials toward the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) is of great significance but still challenging. Herein, an advanced bifunctional electrocatalyst is presented, composed of Fe2P encapsulated in carbon nanowalls decorated with well-dispersed Fe3C nanodots (denoted as Fe2P@Fe3C/CNTs), which is achieved by a novel “inside-out” gas–solid reaction protocol. When functioning as a cathodic catalyst for water splitting, the Fe2P@Fe3C/CNT catalyst needs an ultralow overpotential of 83 mV to deliver a current density of 10 mA cm−2, shows a small Tafel slope of 53 mV dec−1 and ensures long-term stability for over 200 h in an alkaline electrolyte. Notably, the Fe2P@Fe3C/CNT catalyst exhibits an extremely impressive ORR performance with an onset potential (Eonset) of 1.060 V and a half-wave potential (E1/2) of 0.930 V, excellent stability (≈94% activity retention after 36 000 s), and a strong methanol resistance ability, even far outperforming commercial Pt/C (Eonset = 0.955 V, E1/2 = 0.825 V, ≈75% activity retention after less than 3500 s). Such outstanding HER and ORR performances are mainly ascribed to the improved corrosion resistance of the unique Fe2P@C core–shell structures, the abundant catalytically active sites of ultrasmall Fe3C nanodots incorporated in carbon nanowalls, and the good electrical conductivity of 2D graphitic carbon nanotubes used as a support.

In this work, a novel multichromic cationic coordination polymer, named [Zn4(BTC)3(bcbpy)2]·5H2O (1), based on a new flexible viologen ligand 1,1'-bis(3-cyanobenzyl)-[4,4'-bipyridine]-1,1'-diium (H2bcbpy·2Cl), Zn(NO3)2·6H2O and pyromellitic acid (H4BTC) was synthesized. Compound 1 has good photosensitive activity and can respond to sunlight at room temperature. The colour of compound 1 changes rapidly in response to UV light and blue ray irradiation within 5 s. We rarely obtained the crystal structures after irradiation under UV light and blue ray. At the same time, compound 1 shows the hydrochromism phenomenon when heated at 120 °C, and it also shows the ability of detecting aniline and NO2- under low-concentration conditions (10-4 M).

Transition metal nickel sulfide is widely used in supercapacitors and Li-S batteries due to its excellent capacity, low cost, and environmental friendliness. This article is a continuation of our previous studies where the hydrothermal method was used to grow Ni3S4 on the carbon nanofiber network. The physicochemical properties of Ni3S4/CNFs were characterized by XRD, SEM, and XPS methods. Afterward, a Ni-Zn battery was assembled, and its electrochemical properties were analyzed using an electrochemical workstation and a Land system. The discharge specific capacity reached 215 mAh g-1 at a current density of 5 A g-1. After 100 cycles, the battery retained a specific discharge capacity of 176 mAh g-1 and a retention rate of around 82%. A series of tests indicated that the application of Ni3S4/CNFs in aqueous rechargeable Ni-Zn batteries is a feasible and promising approach.

We report the in situ generation of NiCoV-LTH on nickel foam for the HER. Interestingly, the introduction of Co into NiV-LDH can induce the formation of porous nanosheets to expose a large number of active sites and change the electron density around Ni and V to promote the absorption of hydrogen species and thus accelerate the HER kinetics.

Formaldehyde is the most popular and highly toxic indoor pollutants. It is very urgent to develop more sensitive formaldehyde gas sensors with remarkable sensitivity at the ppb level. In this study, for the first time, the olivine-structured Cd2GeO4 was identified as an excellent formaldehyde sensing material. The as-obtained Cd2GeO4 and other sensing materials were well characterized by XRD, SEM, TEM, XPS, scanning Kelvin probe and O2 temperature-programmed desorption techniques. The sensor based on the as-prepared Cd2GeO4 exhibits a high response of 14.1, a short response time (about 5 s) towards 10 ppm formaldehyde and a low detection limit of 60 ppb formaldehyde at a relatively low operating temperature of 140 °C, benefiting the practical application. We believe that the excellent formaldehyde sensing performance should be attributed to the rich chemisorbed oxygen, the small size and the appropriate Fermi level of Cd2GeO4. It can be expected that it will be a promising material for fabricating excellent formaldehyde gas sensors due to its unique sensing characteristics.

Developing cost-effective, highly-active and robust electrocatalysts is of vital importance to supersede noble-metal ones for both hydrogen evolution reactions (HERs) and oxygen reduction reactions (ORRs). Herein, a unique vanadium-mediated space confined strategy is reported to construct a composite structure involving Co/Co9S8 nanoparticles anchored on Co–N-doped porous carbon (VCS@NC) as bifunctional electrocatalysts toward HER and ORR. Benefitting from the ultrafine nanostructure, abundant Co–Nx active sites, large specific surface area and defect-rich carbon framework, the resultant VCS@NC exhibits unexceptionable HER catalytic activity, needing extremely low HER overpotentials in pH-universal media (alkaline: 117 mV, acid: 178 mV, neutral: 210 mV) at a current density of 10 mA cm−2, paralleling at least 100 h catalytic durability. Notably, the VCS@NC catalyst delivers high-efficiency ORR performance in alkaline solution, accompanied with a quite high half wave potential of 0.901 V, far overmatching the commercial Pt/C catalyst. Our research opens up novel insight into engineering highly-efficient multifunctional non-precious metal electrocatalysts by a metal-mediated space-confined strategy in energy storage and conversion system.

A new species from the Qinghai-Tibetan Plateau is described and illustrated. Rhodiola yushuensis S.Y. Meng et J. Zhang sp. nov. is similar to Rhodiola smithii (Hamet) S. H. Fu, but it differs in its inner caudex leaves with obvious petioles and the leaf blades are obovate-triangular (vs. inner caudex leaves with strongly descends to the base of the petiole, and the leaves are long linear) and the outer caudex leaves are scalelike, triangular-suborbicular (vs. scalelike, narrowly triangular). Principal component analysis (PCA) analysis of the leaf traits and seed coat architecture also showed that R. yushuensis can be separated from R. smithii. The nrDNA internal transcribed spacer (ITS) sequences also support the claim that this plant is a new species, and it is grouped with R. smithii.

Plants mainly uptake inorganic nitrogen from soil as ammonium and nitrate. Less energy is required to assimilate ammonium compared to nitrates, and plants prefer to take up ammonium when the external nitrogen concentration is low. Investigating the patterns and mechanisms of ammonium absorption can help improve crop nitrogen utilization. In this study of apple, we isolated MdSAT1, a gene encoding an ammonium-responsive bHLH transcription factor. MdSAT1 promoted the growth and development of lateral roots and root hairs. Overexpression of MdSAT1 increased the transcript levels of genes related to ammonium uptake and assimilation and promoted the activities of ammonium assimilation-related enzymes, indicating that MdSAT1 can enhance ammonium uptake and utilization. MdSAT1 also can modulate ROS accumulation to ultimately regulate plant growth. Taken together, these findings provide insight into the mechanisms by which MdSAT1 controls ammoniun utilization as well as plant growth and development in apple.

Recently, photocatalysts with a hollow mesoporous structure have drawn increasing interest owing to their extensive application in environmental protection. Herein, we prepared hollow mesoporous TiO2 nanospheres decorated with few layer 1T- and 2H- mixed phase MoS2 nanosheets via a template-based method and a hydrothermal reaction. The as-synthesized samples are of hollow mesoporous structure and high specific surface area, providing abundant mass transport and active sites for photocatalytic reaction. 1T-MoS2 in the mixed phase MoS2 mainly play the role as a bridge that transfers photoexcited electrons. Besides, the heterojunction between MoS2 and TiO2 can also efficiently restrain the recombination of photogenerated charge carriers in photocatalysts. As a consequence, under UV–vis light irradiation, the hollow porous TiO2/MoS2 presents a remarkable photocatalytic activity in rhodaming B degradation. Scavenger studies demonstrate that the primary active species in photocatalytic process are hydroxyl radicals. Moreover, a possible photocatalytic reaction mechanism has also been put forward.

Four stoichiometric W-B intermetallic phases, including W2B, WB, WB2 and WB3, are synthesized, and their hydrogen-evolution electrocatalytic properties and electronic structures are investigated comparatively. The electrocatalytic activity for the hydrogen evolution reaction is found to first increase from W2B to WB2 and then decrease; and this activity trend can be rationalized based on their different degrees of hybridization between d orbitals of W and sp orbitals of B.

The decays of $B_{d,s}^0 \to \sigma\sigma, \sigma f_0, f_0 f_0$, with $\sigma$ and $f_0$ denoting the light scalar mesons $f_0(500)$ and $f_0(980)$ in the two-quark picture, are studied in the perturbative QCD approach based on $k_T$ factorization. With the referenced value of the mixing angle $|\varphi| \sim 25^\circ$ for the $\sigma-f_0$ mixing in the quark-flavor basis, it is of great interest to obtain that: (a) these neutral $B$-meson decays into $\sigma\sigma, \sigma f_0$, and $f_0 f_0$ have large branching ratios in the order of $10^{-6} \sim 10^{-4}$, which mean the possibly constructive interferences existed in the decays with different flavor states, and then are expected to be tested at the Large Hadron Collider beauty and/or Belle-II experiments in the (near) future; (b) the large direct CP violations could be easily found in the $B_d^0 \to \sigma\sigma, f_0 f_0$ and $B_{d,s}^0 \to \sigma f_0$ decays, which indicate the considerable interferences between the tree and the penguin decay amplitudes involved in these four modes, and would be confronted with the future measurements; (c) these neutral $B$-meson decays could be examined through the secondary decay chain $\sigma/f_0 \to \pi^+ \pi^-$, namely, the four-body decays of $B_{d,s}^0 \to (\pi^+ \pi^-)_{\sigma(f_0)} (\pi^+ \pi^-)_{\sigma(f_0)}$. On the other side, it seems that other 4 four-body decays of $B_d^0 \to (\pi^+ \pi^-)_{\sigma} (K^+ K^-)_{f_0}$, $B_s^0 \to (\pi^+ \pi^-)_{\sigma(f_0)} (K^+ K^-)_{f_0}$, and $B_s^0 \to (K^+ K^-)_{f_0} (K^+ K^-)_{f_0}$ could also be detected at the relevant experiments, if the $f_0 \to K^+ K^-$ could be identified from the $\phi \to K^+ K^-$ clearly., Comment: 17 pages, 3 figures, 3 tables, references updated, final version to appear in EPJC

Objective The prognostic role of the number of cycles of adjuvant chemotherapy (ACT) after total mesorectal excision in stage III and high-risk stage II rectal cancer is unknown. As a result of this, our study was designed to assess the effect of the number of cycles of ACT on the prediction of cancer-specific survival. Methods Four hundred patients that were diagnosed as stage III and high-risk stage II rectal cancer from January 2012 to January 2018 and who had received total mesorectal excision were enrolled in this study. A nomogram incorporating the number of cycles of ACT was also developed in this study. For internal validation, the bootstrap method was used and the consistency index was used to evaluate the accuracy of the model. The patients were stratified into risk groups according to their tumor characteristics by recursive partitioning analysis. Results We found that the risk of death was decreased by 26% (HR = 0.74, 95% CI: 0.61–0.89, P = 0.0016) with each increasing ACT cycle. The N stage, positive lymph node ratio (PLNR), carcinoembryonic antigen, neutrophil-to-lymphocyte ratio, and the number of cycles of ACT were chosen and entered into the nomogram model. Recursive partitioning analysis-based risk stratification revealed a significant difference in the prognosis in rectal cancer patients with high-risk, intermediate-risk, and low-risk (3-year cancer-specific survival: 0.246 vs. 0.795 vs. 0.968, P < 0.0001). Seven or more cycles of ACT yielded better survival in patients with PLNR ≥ 0.28 but not in patients with PLNR < 0.28. Conclusion In conclusion, the nomogram prognosis model based on the number of cycles of ACT predicted individual prognosis in rectal cancer patients who had undergone total mesorectal excision. These findings further showed that in patients with PLNR ≥ 0.28, no fewer than 7 cycles of ACT are needed to significantly reduce the patient’s risk of death.

Saussurea wettsteiniana is a medicinally important herb endemic to Hengduan Mountains. Here, we report and characterize the complete chloroplast genome sequence of S. wettsteiniana to provide genomic resources useful for future study. The complete chloroplast genome is 152,631 bp in length, consisting of a large single copy and a small single copy of 83,552 bp and 18,637 bp, which were separated by a pair of inverted repeats of 25,221 bp. Totally 133 genes were annotated, including 87 protein-coding genes, 36 tRNA genes, and eight rRNA genes. We also detected two pseudo-genes (ycf1 and rps19). The overall GC content of the whole genome is 37.7%. The phylogenetic tree based on 23 complete plastomes indicated that S. wettsteiniana was closely related to S. involucrata of Compositae.

In this paper, based on the multi-scroll chaotic system, multi-direction chain and grid chaotic attractors are generated by a new Julia fractal mapping process. The feasibility and effectiveness of the proposed method are verified by numerical simulation. This scheme not only realizes the combination of unidirectional and bidirectional distributed multi-scroll chaotic system and Julia fractal, but also applies to three-directional distributed 3D grid-like multi-scroll generalized Jerk system. This paper takes unidirectionally distributed multi-scroll chaos as an example. It discusses the influence of Julia fractals with coefficients and complex constants on the system and generalizes them to the higher-order Julia fractal mapping process. Then, three types of chaotic systems with controllable scroll numbers distributed in multiple directions are obtained. The results of the dynamic analysis method show that the post-fractal chaotic system not only increases the bifurcation interval of its parameters compared with the original chaotic system, but also increases the complexity of its sequence and the maximum Lyapunov exponent, and its attraction domain has a very complex fractal boundary. A kind of multi-directional chain chaotic attractor is realized by the Digital Signal Processors (DSP). The phase diagram of the oscilloscope is consistent with the result of numerical simulation, which verifies the possibility of this method in the digital circuit.

Screening suitable reference genes is the premise of quantitative Real-time PCR(qRT-PCR)for gene expression analysis. To provide stable reference genes for expression analysis of genes in Aconitum vilmorinianum, this study selected 19 candidate re-ference genes(ACT1, ACT2, ACT3, aTUB1, aTUB2, bTUB, 18S rRNA, UBQ, eIF2, eIF3, eIF4, eIF5, CYP, GAPDH1, GAPDH2, PP2A1, PP2A2, ACP, and EF1α) based on the transcriptome data of A. vilmorinianum. qRT-PCR was conducted to profile the expression of these genes in the root, stem, leaf, and flower of A. vilmorinianum. The Ct values showed that 18S rRNA with high expression level and GAPDH2 with large expression difference among organs were not suitable as the reference genes. NormFinder and geNorm showed similar results of the expression stability of the other candidate reference genes and demonstrated PP2A1, EF1α, and CYP as the highly stable ones. However, BestKeeper suggested EF1α, ACT3, and PP2A1 as the top stable genes. In view of the different results from different softwares, the geometric mean method was employed to analyze the expression stability of the candidate re-ference genes, the results of which indicated that PP2A1, EF1α, and ACT3 were the most stable. Based on the comprehensive analysis results of geNorm, NormFinder, BestKeeper, and geometric mean method, PP2A1 and EF1α presented the most stable expression in different organs of A. vilmorinianum. PP2A1 and EF1α were the superior reference genes for gene expression profiling in different organs of A. vilmorinianum.

Here, by a simple one-step in situ chemical reduction method, the AgxCuy alloy was tailored on the surface of mesoporous TiO2 (M-TiO2), therefore, a series of bi-functional mesoporous TiO2 nanohybrids (M-TiO2/AgxCuy) for both surface enhanced Raman scattering (SERS) detection and photocatalytic degradation of ampicillin (AMP) were achieved. The composition and structure of the nanohybrids were well characterized using XRD, TEM, XPS and HRTEM-EDS measurements. Results indicated that AgxCuy alloy was mainly attached around the pores of M-TiO2 which may generate more active sites than nonporous P25−Ag−Cu. Thus, the M-TiO2/AgxCuy nanohybrids could be used as efficient SERS substrates to sensitively monitor the AMP in water with lower detection limit (˜ 1 ppt) than P25−Ag−Cu. Besides, the M-TiO2/Ag3Cu1 nanohybrid also showed higher photocatalytic activities for the degradation of AMP under UV irradiation over the M-TiO2/Ag, the M-TiO2/Cu and the P25−Ag−Cu. This work provided a simple and effective approach to synthesize bi-functional nanohybrids for detection and degradation of organic contaminants in wastewater.

Purpose: The present study retrospectively analyzed thesafety and efficacy of computed tomography (CT)-guided cryoablationin the treatment ofunresectable or recurrent advanced colorectal cancer, which did not respond well to or experienced progression with radiotherapy or chemotherapy.Materials and Methods: From January 2013 to April 2015, 31 lesions in 27 patients (16 males, 11 females; mean age of 57.2 years) with pelvic unresectableadvanced or recurrent colorectal cancer were included in the study. The tumor diameter was approximately 3.37 ±1.41 cm. The primary tumor included 25 rectal cancers, 1 sigmoid colon adenocarcinoma, and 1 ileocecal mucinous adenocarcinoma. Cryoablation was performed with 17-gauge cryoprobes and monitored by 64-slice spiral CT. Follow-up was carried out by contrast-enhanced magnetic resonance imaging (MRI). The treatment efficacy was evaluated by symptom palliation, decreased carcinoembryonic antigen (CEA) serum level, and tumor response.Results: The cryoablation procedure was well-tolerated in all patients without major complications or procedure-related mortality. Long-term complications included abscess formation (1 patient), skin frostbite and post-sacrum antrum formation (1 patient). Pain relief was satisfactory in patients with perineal pain (P

Development of photocatalysts with high activity and durability for hydrogen generation is extremely desired but still remains a great challenge currently. With Cu nanoparticles (Cu NPs) as a linker between TiO2 microsphere (TiO2 MS) and 5, 10, 15, 20-meso-tetra(4-carboxyphenyl)porphyrin (TCPP), a novel nano-micro hybrid (TiO2 MS-Cu-TCPP) was prepared via a facile method. By bridging TiO2 MS and TCPP with Cu NPs, the absorption and the electron transfer of TiO2 MS were greatly improved. When the TiO2 MS-Cu-TCPP was employed as the photocatalyst for hydrogen evolution, it exhibited higher activity and stability than those of the TiO2 MS, the TiO2 MS-Cu and the TiO2 MS-TCPP, TiO2 MS-Cu-CuTCPP and TiO2 MS-TCPP-Cu. The photocatalytic activity was enhanced for about 6 times with respect to that of the pristine TiO2 MS. The excellent performance for the nano-micro hybrid can be attributed to wide light absorption, more reactive sites, and facilitated interfacial electron transfer owing to the strong interaction between TiO2 and TCPP with Cu NPs as the linker and cocatalyst. Subsequently, a high and stable photocatalytic activity over the TiO2 MS-Cu-TCPP nano-micro hybrid was achieved, demonstrating the importance of interfacial modification to a semiconductor photocatalyst. This result gives us a new perspective of constructing special structures for efficient light utilization and electron transfer.

Development of highly active photocatalysts is one of the key topics for H2 production. Modifying the microstructure and exploring the electron transfer mechanism of the materials are very vital to achieve high-quality catalysts. Herein, by means of the bridging of rare-earth ions (Ln), a novel nanohybrid (GO–Ln–DPDPP) constructed of graphene oxide (GO) pillared with 5,15-diphenyl-10,20-di(4-pyridyl)porphyrin (DPDPP) was prepared by electrostatic interaction combined with coordination interaction. It was shown that the microstructure and morphology of the nanohybrid were greatly affected by the Ln introduced. Meanwhile, photoproduced electron transfer in the hybrid can be effectively promoted by the Ln implanted in the GO. Photocatalytic H2 production and the electron transfer mechanism were further explored. It was shown that, on the basis of the bridging of the Ln, lower interfacial resistance and higher separation of electron and hole caused by the strong interaction between DPDPP and GO were responsib...

In this paper the cavitation phenomenon and bubble collapse in submerged water jet added with CTAC were studied. The cavitation simulation was based on an improved cavitation model established by introducing coefficients into traditional cavitation model. The coefficients were obtained by fitting the numerical solutions of Rayleigh-Plesset equation in which the viscosity term and surface tension term were not neglected. Cross model was also employed to express the shear-thinning character of the surfactant solution. Simulation results show that the whole cavitation intensity decreased but the scale of cavitation region increased in drag-reducer solution. The submerged water jet added with drag-reducer was less dispersed and the stagnation pressure near the wall was significantly improved. Simulation results of the bubble collapse process show that the bubble collapsed more slowly in drag-reducer solution in comparison with that in pure water. The two pressure peaks near the wall during the collapse process appeared later in drag-reducer solution and the maximum value of the pressure generated in drag-reducer solution was less than that in pure water.

A numerical study on cavitation in the centrifugal pump during the transportation of pure water and diesel is carried out. An improved cavitation model based on the Zwart–Gerber–Belamri Model is employed in the simulation. A Cash–Karp fourth–fifth order Runge–Kutta method was used to solve the original Rayleigh-Plesset equation to get the numerical solution. The effects from viscosity and surface tension on bubbles’ expansion and compression are taken into account in the improved model instead of the traditional simplification in which the bubble radius is just a function of pressure and density. The coefficients got by fitting the numerical solution are added to the constant pre-multiplier of the Zwart-Gerber-Belrami cavitation model and finally enhance the model. The vapor volume fraction was predicted to be larger in diesel compared to water. The distribution of pressure in diesel is more homogenous than that in pure water. Keywords: Pump, Cavitation, Viscosity, Surface tension, Simulation

The selective detection of methyl benzene (e.g. toluene and xylene) using oxide semiconductor-based gas/vapor sensors is highly desirable but limited by the low chemical reactivity of the benzene compounds. Exploiting p-type semiconductor oxides (e.g., NiO) which provide distinctive catalytic activities for methyl benzene detection is an essential approach. However, the intrinsic responses of p-type semiconductor oxides are often low. In this paper, high-performance toluene and xylene detection has been realized by a sensor based on novel p-p heterojunction NiGa2O4-NiO nanospheres. Construction of optimized p-p heterojunctions, which resulting from the rationally controlling of the NiGa2O4 content in NiGa2O4-NiO, leads to significantly promoted sensing properties for toluene and xylene detection. It is found that the sensor based on 50% NiGa2O4-NiO exhibits the best sensing performances. Its highest response (Rg/Ra = 12.7 to toluene; Rg/Ra = 16.3 to xylene) is almost 10 times higher than that of the pure NiO (Rg/Ra

Development of highly-active photocatalyst is of critical challenge for hydrogen production from water reduction, and optimizing the microstructure and the composition of the relative materials is very necessary to obtain the high-quality catalysts. Here, a novel self-adjusting structure of pompoms-like cadmium molybdate nano-micro hybrid stimulated by copper ions (Cu-CdMoO4) was achieved. It was found that the morphology and property of the CdMoO4 can be modulated greatly by the Cu. The optimal H2 generation amount for the hybrid was about 77.4 times higher than that of pure CdMoO4 under same conditions. The significantly improved activity is associated with wider light response, more active sites, and effective charge separation.

The development of highly active, stable and low-cost non-noble metal catalysts for hydrogen evolution reaction (HER) is extremely imperative. Multi-metal based electrocatalysts have recently become an emerging class of hydrogen evolution reaction (HER) electrocatalysts due to their excellent electrical conductivity and synergistic effects from metal atoms. However, the relationship between the cation and its intrinsic electrocatalytic properties in multi-metallic electrocatalysts is still not clear. Herein, we report a facile method for the preparation of surface-clean, phase-pure bimetallic (or multi-metallic) carbides through the solid reaction between metal salts and carbon nanotubes under an inert atmosphere. These multi-metallic carbides include molybdenum-based carbides (Co3Mo3C and Fe3Mo3C), tungsten-based carbides (Co6W6C, Ni6W6C and Fe6W6C) and trimetallic carbides (CoxFe3−xMo3C and CoxFe6−xW6C). Based on the synergistic effect of the metal atoms, the catalytic activities of the resulting bimetallic and trimetallic carbides are significantly improved compared to that of the single-metal carbides. The catalytic activity of the metal carbides decrease in the order of Co-based > Ni-based > Fe-based and Mo-based > W-based. Among them, Co3Mo3C has an optimized catalytic activity, offering a current density of 10 mA cm−2 at a low overpotential of 169 mV. Our study provides a controllable method for the preparation of the multi-metallic carbides and further justifies that the multi-metallic carbides are effective catalysts for HER.

A family of twelve monometallic diborides, containing transition metals from group IVB elements to group VIII elements, and Ni-W bimetallic diborides are synthesized via a molten salt-assisted method. Their trend in activity for the hydrogen evolution reaction is studied, with Ni-W bimetallic diborides acting as the most efficient, nonprecious electrocatalysts.

Formaldehyde is one of the most harmful environmental toxins, which should be less than 60 ppb indoors. Although some sensors, based on metal oxide semiconductors, are fabricated for the detection of formaldehyde, the sensing performance is not satisfactory yet. In this work, some rare earth metals are successfully introduced into In2O3 by a simple electrospinning method. The structure, composition and chemical state of the products are investigated by XRD, TEM, EDS, XPS, TPD and a Kelvin probe. And the sensor based on 5Y-doped In2O3 exhibits the highest response to formaldehyde. Moreover, this sensor also shows an ultra-low detection limit (50 ppb), a short response time (1 s) and good selectivity. It is believed that the improved sensing response and selectivity may originate from the elevated Fermi level and the increased surface basicity of In2O3, leading to the increase of chemisorbed oxygen on the surface and adsorption of formaldehyde.

Nonwoven geotextiles are widely used in tailings ponds for filtration and drainage, but there is a risk of failure of nonwoven geotextile due to physical clogging. In this study, to reduce the clogging of nonwoven geotextile filter in tailings ponds and improve its long-term drainage performance, a layer of woven geotextile is placed between tailings and nonwoven geotextile to form a composite filter of woven-nonwoven geotextile. A series of gradient ratio tests were conducted to study the influence of the aperture of woven geotextile on the filtration characteristics of composite filter. The long-term filtration performance of composite filter was evaluated, and the filtration mechanism of composite filter was revealed. The results show that after adding a layer of woven geotextile with reasonable aperture upon the nonwoven geotextile, the gradient ratio of filter decreased and the flow rate of filter significantly increased. The filtration performance of composite filter of geotextile was better than that of nonwoven geotextile filter. The aperture of woven geotextile had an important influence on the filtration characteristics of composite filter. With the increase of the aperture of woven geotextile, the gradient ratio value of the composite filter decreased first and then increased. For relatively dense tailings, the recommended ratio of the equivalent aperture of woven geotextile (O95) to the characteristic particle diameter of tailings (d85) s is about 1.6.