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A series of linear diborazanes (R1R2R3NBH2NH2BH3, R1, R2, R3 = H, Me, Et, nPr, iPr) have been synthesized at room temperature by the reaction of aminodiborane (ADB) with alkylamine. Theoretical calculations demonstrate that the formation mechanism of the linear diborazanes is a one-step nucleophilic reaction, where the amine molecule approaches a B atom along a line nearly colinear with a B–Hbridging bond in the ADB, and the nucleophilic reaction is controlled by thermodynamics and can occur spontaneously. The crystal structure of the linear diborazanes is affected not only by the capped alkylamine, but also by the extensive dihydrogen bonds. Both anti and gauche conformations of the linear diborazanes are observed, which are stabilized by inter-/intramolecular DHBs.

Furosemide, abbreviated as FS, is a loop diuretic drug with low solubility and permeability. Herein, three adducts derived from FS and hexamethylenetetramine (HTEM), amantadine (AMD) and isonicotin...

N-doped hierarchically structured carbon pellicles (CZIF-8/PAN) were prepared from the carbonization of zeolitic imidazolate framework (ZIF-8)/polyacrylonitrile (PAN) composite fibers which were fabricated by electrospinning technique. The resultant free-standing nanofiberic pellicles can be cut into membrane disks and directly used as anode materials without any binder and additive. As an anode for sodium-ion batteries (SIBs), the CZIF-8/PAN nanofiberic carbon pellicles showed superior reversible capacities of 186.2 mAh g−1 at high current density of 1.0 A g−1 and an excellent cyclic stability (93.5% remaining after 600 cycles) compared to other similar reported carbonaceous anode materials for SIBs. The improved electrochemical performance of CZIF-8/PAN carbon pellicles is mainly attributed to the hierarchical porous structures produced by introducing large ZIF-8 particles as a template, which greatly promotes the large sodium cation transportation and electron transfer rates due to the enlarged pores and increased contact area between the electrode and electrolyte. In addition, the enhanced electrochemical performance of CZIF-8/PAN nanofiberic anodes also benefits from the doping of nitrogen atoms which enhance the conductivity and increase the active sites.

Nicotinic acid (NA), known as vitamin B3, has been widely studied in pharmaceutical science. Herein, three salts derived from NA and (1R,2R)-1,2-diphenylethylenediamine (DPEN), including one solvent-free salt (DPEN)(NA)2 and two solvated salts, (DPEN)(NA)2(EA) and (DPEN)(NA)2(ACN) (EA: ethyl acetate, ACN: acetonitrile), have been obtained and characterized by solid-state techniques. By the investigation of single-crystal structures, the synthons, acid–ammonium heterodimer and Nammonium—H...Npyridine between functional groups of 1,2-diphenylethylenediammonium and NA are revealed and further identified using Hirshfeld surface analysis. The utility of the synthons is further demonstrated by making salts with the NA isomer, isonicotinic acid. Here the synthon occurrences in cocrystals/salts of NA (including NA derivatives) and diamine coformers reported in the Cambridge Structure Database (CSD) are compared. The robustness of acid–ammonium heterodimer and Nammonium—H...Npyridine is investigated by a search of the CSD. The NA salts also show their improved solubility in pH 1.2, 4.5 and 6.8 buffer mediums compared with pure NA material.

Owing to the high working voltage and energy-storage density and excellent cycling stability, Na3V2(PO4)2O2F (NVPOF) has been recognized as a promising cathode material for sodium ion batteries (SIBs). Usually, NVPOF is prepared by a high-temperature solid-state method, which easily leads to many deficiencies including large particle size, irregular morphology and poor high-rate capability. In order to avoid these deficiencies, the present study reveals a simple hydrothermal method to effectively regulate the morphology and size uniformity of the NVPOF particles and optimize the electrochemical properties by precisely adjusting the key preparation parameters including pH and temperature. It is disclosed that the optimized NVPOF prepared at pH = 7.00 ± 0.05 and 170 °C can achieve outstanding electrochemical properties in terms of high specific capacity of 123.2 mA h g−1 at 0.1 C, superior high-rate capability of 85.9 mA h g−1 at 20 C and long cycling stability (e.g., a capacity retention up to 94.8% at 1 C after 500 cycles). All of the properties are obviously better than those of the controls obtained at other preparation parameters. The much enhanced performance should be beneficial from the short and fast Na+ transport pathways because of the high uniformity and nanometer size of the NVPOF particles, making them a promising cathode material for high-performance SIBs.

Objectives: The aim of this study is to evaluate the analgesic effect of erector spinae plane block (ESPB) in patients undergoing thoracic surgery. Methods: We systematically searched Embase, PubMed, The Cochrane Library, VIP database, CNKI, Wanfang database, CBM, from 2010 to December, 2020 to perform a meta-analysis of randomized controlled trials (RCTs) on the analgesic effect of ESPB in thoracic surgery patients. The primary outcome were postoperative pain scores at various time points. Results: Eighteen studies with a total of 1303 patients were included. The meta-analysis found that ESPB reduced postoperative 48-hour pain scores at rest or movement at different time points compared with the control group, reduced the incidence of postoperative nausea and vomiting (PONV) (odds ratio, OR = 0.48, 95% CI = 0.33∼0.71, P < 0.05), and reduced the number of patient-controlled intravenous analgesia (PCIA) pressing times (mean difference, MD = −6.83, 95% CI = −8.73∼−4.94, P < 0.05). Conclusions: Compared with general anesthesia (GA), GA combined with ESPB significantly decreases postoperative pain, PONV and opioids requirements following thoracic surgery.

A facile and efficient cyclization of sodium aminodiboranate to construct a boron-nitrogen-hydrogen ring is presented. This new strategy can be developed into a general method to prepare aminodiborane and its derivatives. Theoretical calculations show that a one-step cyclization mechanism is favored, where the dihydrogen bond plays an important role.

Metal–organic frameworks (MOFs), which are constructed from the assembly of metal ions or metal clusters with organic linkers, represent a new class of crystalline porous materials with potential applications in the fields of gas storage and separation, heterogeneous catalysis and chemical sensing. The development of reliable and reproducible methods to fabricate MOFs with high stability and mesopore characters remains a great challenge to meet many future applications for separation, large molecules adsorption, drug delivery and size-selective catalysis and so on. In this tutorial review, we are mainly focusing on the recent developments in the fabrication of hierarchically structured MOFs based on nanoscience techniques.

Recently, sodium-ion batteries (SIBs) have been considered as the promising alternative for lithium-ion batteries. Although layered P2-type transition metal oxides are an important class of cathode materials for SIBs, there are still some hurdles for the practical applications, including low specific capacity as well as poor cycling and rate properties. In this study, the electrochemical properties of layered Mn-based oxides have been effectively improved via Al doping, which cannot only promote the formation of layered P2-type structure in the preparation processes but also stabilize the lattice during the successive Na-intercalation/deintercalation due to suppression of the Jahn-Teller distortion of Mn3+. Among the as-prepared series of Na2/3Mn1-xAlxO2 (x = 0, 1/18, 1/9, and 2/9), Na2/3Mn8/9Al1/9O2 with x = 1/9 exhibits the optimal doping effect with the best electrochemical properties, in terms of the highest specific capacity of 162.3 mA h g−1 at 0.1 C, the highest rate capability, and the best cycling stability in comparison to the undoped Na2/3MnO2 and the other two materials with different Al-doped contents. Both cyclic voltammetry at varied scan rates and galvanostatic intermittent titration technique disclose the optimal electrode kinetics (the highest Na-diffusion coefficient) of the best Na2/3Mn8/9Al1/9O2.

Layered P2-type Na0.53MnO2 nanorods is prepared by a simple solution reaction. When used as cathode material for sodium ion batteries, the P2-Na0.53MnO2 delivers a high reversible capacity up to 135.7 mA h g−1 (theoretical capacity is 140 mA h g−1) at 0.1 C in the voltage range of 2–4.3 V vs. Na+/Na, corresponding to 0.51 mol of Na insertion/extraction. It presents good cycling performance and high rate capabilities. After 50 cycles, the capacity is just fading about 6.8% at the rate of 2 C. The significant behaviour of fast charging makes it be very attractive for practical application. The electrochemical impedance spectroscopy and galvanostatic intermittent titration technique are employed to investigate its sodium diffusion kinetics. The ex-situ X-ray diffraction technology is also used to study the intercalation/de-intercalation of sodium ions and the phase transition in the charging/discharging processes.

Sodium-ion batteries (SIBs) represent a promising alternative to lithium-ion batteries, owing to the much higher abundance and lower cost of sodium resources in comparison with lithium. However, the electrode materials of SIBs usually suffer from more severe issues, such as low specific capacity and poor cyclability, owing to the much larger Na+ diameter and drastic volumetric variations during sodiation/desodiation. Hence, it is still a huge challenge to develop superior electrode materials for reversible Na storage. In comparison with the crystalline materials conventionally used in batteries, amorphous ones may offer a more stable framework for the uptake of Na. To address these issues, a porous composite composed of amorphous Co2P and N,B-co-doped carbon (A-Co2P/CxNyBz-650) is prepared by controlling the annealing temperature at 650 °C after freeze-drying the precursors. As-prepared A-Co2P/CxNyBz-650 exhibits much better Na-storage properties in terms of higher Na-storage capacity, longer cycling stability, and excellent rate performance compared with the crystalline counterparts. These may benefit from the fact that the amorphous framework can provide easier Na+ accessibility and better strain accommodation, originating from volumetric variations during sodiation/desodiation. More importantly, the electrolyte for all of the electrochemical tests are NaPF6 based, which is more accessible for practical applications because of its higher safety compared with the commonly used NaClO4-based electrolyte.

Novel hybrid batteries are fabricated using an aluminum anode, a sodium intercalation cathode Na3V2(PO4)3 (NVP), and a sodium/aluminum dual salt electrolyte based on NaAlCl4 and an eutectic mixture of 1-ethyl-3-methylimidazolium chloride (EMImC) and aluminum chloride. Cyclic voltammograms indicate that increasing the molar concentration of AlCl3 in the electrolyte is beneficial to high coulombic efficiency of aluminum deposition/stripping, which, unfortunately, results in lower coulombic efficiency of sodium extraction/insertion in the cathode. Therefore, EMImC–AlCl3 with a molar ratio of 1–1.1 is used for battery evaluation. The hybrid battery with 1.0 M NaAlCl4 exhibits a discharge voltage of 1.25 V and a cathodic capacity of 99 mA h g−1 at a current rate of C/10. In addition, the hybrid battery exhibits good rate performance and long-term cycling stability while maintaining a high coulombic efficiency of 98%. It is also demonstrated that increasing salt concentration can further enhance the cycling performance of the hybrid battery. X-ray diffraction analysis of the NVP electrodes under different conditions confirms that the main cathode reaction is indeed Na extraction/insertion. Based on all earth-abundant elements, the new Na–Al hybrid battery is very attractive for stationary and grid energy storage applications.

24-Alkyl sterols are the major players in the control of membrane component and plant growth. In this paper, we cloned an important rate-limiting enzyme: sterol-C-24-methyl transferase (SMT) in the sterol biosynthetic pathway according to the transcriptome data of Tripterygium wilfordii. suspension cells, whose full-length c DNA was 1 631 bp with an open reading frame of 1 080 bp, encoding a protein of 359 amino acids. It was estimated that theoretical isoelectric point (pI) was 6.43 and the molecular mass was 40.0 kDa. Bioinformatics analysis attributed the SMT gene to SMT2 family. The expression vector was constructed as the pMAL-c2x-TwSMT2 plasmid and the recombinant protein was expressed in E. coil BL21(DE3) competent cells. After methyl jasmonate treatment, the relative expression level of TwSMT2 has improved significantly in 24 h. SDS-PAGE electrophoresis and Western Blot showed that protein of TwSMT2 in BL21 (DE3) strain was expressed after induction by IPTG. In this study, Tw SMT2 was cloned for the first time and the recombinant protein was expressed, which lay the foundation for elucidation of the sterol biosynthetic pathway of Tripterygium wilfordii in the future.

Cryptomeridiol, a typical eudesmane diol, is the active principle component of the antispasmodic Proximol. Although it has been used for many years, the biosynthesis pathway of cryptomeridiol has remained blur. Among terpenoid natural products, terpenoid cyclases are responsible for cyclization and generation of hydrocarbon backbones. The cyclization is mediated by carbocationic cascades and ultimately terminated via deprotonation or nucleophilic capture. Isoprene precursors are, respectively, converted into hydrocarbons or hydroxylated backbones. A sesquiterpene cyclase in

In recent years, graphene-incorporated micro-/nanocomposites represent one of the hottest developing directions for the composite materials. However, a large number of active nanoparticles (NPs) are still in the unprotected state in most constructed graphene-containing designs, which will seriously impair the effects of the graphene additives. Here, a fully protected Fe3O4-based micro-/nanocomposite (G/Fe3O4@C) is rationally developed by carbon-boxing the common graphene/Fe3O4 microparticulates (G/Fe3O4). The processes and results of full protection are tracked in detail and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and nitrogen absorption–desorption isotherms, as well as scanning and transition electron microscopy. When used as the anode for lithium-ion batteries, the fully protected G/Fe3O4@C exhibits the best lithium-storage properties in terms of the highest rate capabilities and the longest cycle life compared to the common G/Fe3O4 composites and commercial Fe3O4 products. These much improved properties are mainly attributed to its novel structural features including complete protection of active Fe3O4 nanoparticles by the surface carbon box, a robust conductive network composed of nitrogen-doped graphene nanosheets, ultra-small Fe3O4 NPs of 4–5 nm, abundant mesopores to accommodate the volume variation during cycling, and micrometer-sized secondary particles.

In this paper, we study the group decision making (GDM) problem with two-tuple linguistic information .we propose a way to calculate the comprehensive assessment information. Then average preference degree of one alternative over all the other alternatives is calculated. Thus, the ranking of alternatives is obtained by the comparison of linguistic two-tuple information.

Graphene material prepared by reducing graphene oxide (GO, prepared by the modified Hummers method) has been considered as one of the most promising candidates for electrode materials for supercapacitors due to its mass producibility, high electrical conductivity, large specific surface area, and superior mechanical strength. However, it usually exhibits an unfavorable cycling performance, mainly large capacitance fading in the initial thousands of cycles, as shown but not discussed in some previous reports. In this paper, we not only find a similar phenomenon to a commercial graphene material, but also develop a very simple method to successfully enhance its electrochemical properties in terms of cycle life as well as high-rate performance, leakage current and alternating current impedance. For example, the relatively low capacitance retention of about 89.9% at the initial 1000th cycle was increased up to 99.7% after improvement, the capacitance retention was raised to 73% from 43% at a scan rate of 100 mV s−1 in cyclic voltammetry, and leakage current density was significantly more than halved (from 2.42 mA g−1 to 1.01 mA g−1). Additionally, the reasons for the improvement are also disclosed by analyzing the characterization results of X-ray photoelectron spectroscopy, electrochemical impedance spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy and Raman spectroscopy. It is found that the optimization of the functional groups of doped nitrogen and oxygen atoms may contribute to the improvement of cycle life and decrease of leakage current density, and the enhanced rate performance can be attributed to the increase of electrical conductivity.

A metallic nanotube composed of the ferromagnetic spin-3/2 inner shell and spin-1 outer shell with a ferrimagnetic interlayer coupling has been studied by using the effective-field theory with correlations (EFT). With both existence of the magnetic anisotropy and transverse field, we have studied effects of them on the magnetic properties and the thermodynamics. Some interesting phenomena have been found in the phase diagrams. At low temperature, the magnetization curves present different behaviors. Two compensation points have been found for the certain values of the system parameters in the system. The research results of metallic nanotubes may have potential applications in the fields of biomedicine and molecular devices.

To compare the influence of porosity on bending strength, density, viscosity of slurry of dental zirconia-toughened alumina(Ce-TZP/A) ceramic by gel-casting technique. Ce-TZP/A composite ceramic powder was made from a Al2O3 of micron grade and 3Ce-ZrO2 of nanometer grade, with sintering additives of MgO and TiO2. The slurries of 5(v/v), 52%, 54%, 56% ,58% and 60% were prepared separately, and sintered at 1200°C after in situ molding using gel-casting. The properties such as bending strength, density, viscosity of slurry of specimens were measure and compared. Slurry was prepared with optimum solid content, and applied to form dental CeTZP/A basal crown on the plaster die. The marginal fitness of crowns was observed after sintered. The mean viscosity of slurry (PaS) were: 0.27±0.05, 0.31±0.1, 0.33±0.09, 0.96±0.12, 1.01±0.07, 1.21±0.02. The effect of solid loading (P=0.05) were significant. The mean bending strength (MPa) were: 43.15±0.8, 47.9±1.5, 50.09±1.7, 58.12±1.9, 39.17±1.6, 35.08±1.2. The mean toughness (MPa m^1/2) were: 17.6±0.8, 16.9±0.6, 16.1±0.5, 17.8±0.9, 18.6±0.8, 20.5±0.2. The mean density (g/cm) were: 5.32±0.9, 5.43±0.8, 6.13±0.5, 6.01±0.5, 5.13±0.3, 5.05±0.4. The specimen formed from slurry of 52(v/v) had better properties than that of others solid loading after sintered at 1150º. With the solid loading increased, the viscosity of slurry has a significantly improved.

The compound tribenzylamine (TBA) and its derivatives are a type of classical tripodal ligands in building up diversity of supramolecular arrays or networks. In the present contribution, we described two new supramolecular complexes 2[C21H22N+]·[CoCl4]2−·(1) and 2[C21H22N+]·[CuCl4]2− (2) by reacting protonated TBA with CoCl2·6H2O/CuCl2·2H2O. Different from previous TBA supramolecular complexes, these two supramolecular complexes were easier to obtain by grinding protonated TBA and CoCl2·6H2O/CuCl2·2H2O in an agate mortar than using conventional solution method. The two supramolecular complexes form fascinating 3D helical architectures, with two types of interwoven helical chains involved inside the structures. A comparison of the geometries of TBA in these two supramolecular complexes with the previously reported TBA supramolecular complexes shows that the significant differences are due to the conformation of the three arms of phenyl rings around the N center. Two new tribenzylamine (TBA) supramolecular complexes 2[C21H22N+]·[CoCl4]2− (1) and 2[C21H22N+]·[CuCl4]2− (2) were obtained by reacting protonated TBA with CoCl2·6H2O/CuCl2·2H2O. The two supramolecular complexes form fascinating 3D helical architectures, with two types of interwoven helical chains involved inside the structures.

Honeycombed SnO2 is synthesized by a simple wet chemical method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, and N2 adsorption–desorption isotherms. The porous diameter of the honeycombed SnO2 is about 2 μm. Sensing investigation reveals that the obtained SnO2 with a very small BET surface area (19.7 m2 g−1) owns ultra sensitive properties to H2 at 340 °C. The response is 8.4 when the sensors are exposed to 1 ppm H2, and the response and recovery times are 4 and 10 s, respectively. The theoretical model for the infection of porous diameter on the sensing properties is provided.

A hexagonal nanowire consists of the ferromagnetic spin-3/2 core and spin-1 outer shell coupled with ferrimagnetic interlayer coupling has been studied. The general formula for the temperature dependence of the longitudinal and the transverse magnetization of the system is given. Particularly, emphases of the effects of the physical parameters on transition temperature and the range of physical parameters over which two compensation points exist are given. The competition among the exchange coupling between the outer shell and core, the outer shell coupling, the anisotropies, the transverse field, and the temperature has a profound effect on the characteristic of magnetic properties in the hexagonal nanowire system.

Forest resources are one of the most important resources which men are survival of. We studied sustainable development tactics of regional forest resources . Volume model, describing the growing process of a tree, was built to establish the relationship between the age of grown up and the age of grow stagnation; also 1-D dynamic discrete model was established, considering the characteristic of number of trees in different ages in the condition that there is only a single kind of tree in the forest firstly; then multidimensional dynamic discrete model was formulated, providing the best felling policy that can meet lumber demand and have better age of stand structure. The simulation results show that the age of stand structure finally reach steadiness in one million hectares. Regional forest achieve sustainable development.

Magnetic properties of the cubic nanowire, which consists of a ferromagnetic core of spin-1 and a ferromagnetic shell of spin-3/2 with ferrimagnetic interface coupling, are investigated by the use of the effective-field theory with correlations (EFT). Two compensation points have been found for certain values of the system parameters in the nanowire. In particular, the effects of the transverse field and the crystal field on the magnetization and phase transition are described in detail.

In this study, we cloned a monoterpene synthases, TwMS from Tripterygium wilfordii suspension cells. TwMS gene contained a 1 797 bp open reading frame (ORF), encoding a polypeptide of 579 amino acids, which deduced isoelectric point (pI) was 6.10 and the calculated molecular weight was 69.75 kDa. Bioinformation analysis showed that the sequence of TwMS was consistent with the feature of monoterpene synthases. Differential expression analysis revealed that the relative expression level of TwMS increased significantly after being induced by methyl jasmonate (MeJA). The highest expression level occurred at 24 h. TwMS protein was successfully expressed in Escherichia coli BL21 (DE3), which laid the foundation for identifying the function of T. wilfordii monoterpene synthases.

Kaurenoic acid oxidase involved in biosynthesis pathway of gibberellin. According to the transcriptome database, the specific primers were designed and used in cloning the full-length cDNA of TwKAO, the bioinformatic analysis of the sequence was performed. The qRT-PCR were used to detect the expression level of TwKAO after MeJA treatment.The full-length cDNA of the TwKAO was 1 874 bp encoding a polypeptide of 487 amino acids.The calculate molecular weight was about 56.02 kDa,and the theoretical isoelectric point (pI) was 8.89. The relative expression level of TwKAO was deduced by MeJA and reached the highest at 12 h after the treatment.Plant tissue expression analysis indicated that, TwKAO expressed the highest in leaves,while lowest in roots.For the first time, we cloned and analyzed the expression characteristics of TwKAO, which laid a foundation for deep analysis of growing development and terpenoid secondary metabolites in T. wilfordii.

Based on the transcriptome data, the study cloned full-length cDNA of TwGPPS1 and TwGPPS2 genes from Tripterygium wilfordii suspension cells and then analyzed the bioinformation of the sequence and protein expression. The cloned TwGPPS1 has a 1 278 bp open reading frame (ORF) encoding a polypeptide of 425 amino acids. The deduced isoelectric point (pI) was 6.68, a calculated molecular weight was about 47.189 kDa. The full-length cDNA of the TwGPPS2 contains a 1 269 bp open reading frame (ORF) encoding a polypeptide of 422 amino acids. The deduced isoelectric point (pI) was 6.71, a calculated molecular weight was about 46.774 kDa.The entire reading frame of TwGPPS1,2 was cloned into the pET-32a(+) vector and expressed in E. coli BL21 (DE3) cells to obtain the TwGPPS protein, which laid a basis for further study on the regulation of terpenoid secondary metabolism and biological synthesis.

The magnetization of a ferrimagnetic mixed-spin nanoparticle for a series of different single-ion anisotropies D1 and D2 with increasing external magnetic field is studied by the use of the effective-field theory with correlations. At low temperature, the magnetization exhibits an obvious step effect for different anisotropies, exchange couplings, and external magnetic field. The results show that the positive single-ion anisotropy D1 (or D2) is a necessary element for the emergence of the accessional magnetization plateaus for the ferrimagnetic mixed-spin nanoparticle. However, for the stronger D2 the magnetization plateaus dissatisfy the 2S+1 criterion in such a ferrimagnetic nanoparticle system.

In this study, we have deliberately utilized the second-sphere coordination approach into the construction of supramolecular inclusion solids Cl ⊂ [H2L1]·[InCl4] (Crystal I) and Br ⊂ [H2L1]·[TeBr6] (Crystal II). The chloride or bromine anions can be encapsulated inside the host assemblies formed by the diamine molecule (4,6-dimethyl-1,3-phenylene) bis(N,N-dibenzylmethane) (L1) and the metal complexes ([InCl4]− and [TeBr6]2−) via second-sphere interactions. The inclusion complexes have been structurally characterized by X-ray crystallography, indicating that weak C–H···Cl and C–H···Br hydrogen bonding synthons play a significant role in the construction of host framework. 2-D networks are formed in both complexes by the interconnection of 1-D networks through the multiple weak hydrogen bonding interactions with [InCl4]− or [TeBr6]2−. The guest Cl− or Br− anions are encapsulated inside the host cages through N–H···Cl hydrogen bonds. The inclusion selectively was studied for the two host assemblies.

The magnetic properties of a nanoparticle described by the transverse Ising model with single-ion anisotropis, which consists of a concentric spin-3/2 core and a hexagonal ring spin-5/2 shell coupled with a ferrimamagnetic interlayer coupling, are studied by the effective-field theory with self-spin correlations. Particular emphasis is given to the effects of the both the transverse field and the single-ion anisotropis on the longitudinal and transverse magnetizations, phase diagrams of the nanoparticle. We have found that, for appropriate values of the system parameters, one or two compensation points may be obtained in the present systems.

The circular layout of the heat transfer soil tank experiments on the dynamic transmission of underground storage mechanism. By analyzing and comparing the dynamic and static, with or without heat shield of the storage conditions, explore ways to make a favorable energy storage ,which has better effect on energy injected and preservation. The results show that, compared to the static continuous loading , intermittent loading and storage with heat shield are more conducive to the storage of energy injected and improve the ability of cohesion of temperature field; controlling the ratio of the heat for the heat shield to the total load is the key issues on application of heat screen.

The reverse micellar peroxotitanium-containing catalyst [C18H37N(CH3)3]7[PW10Ti2O38(O2)2] was assembled in the organic solvent and the structure was characterized by Fourier transform infrared spectroscopy(FT-IR), Diffuse reflectance UV–vis spectrum (DR-UV–vis), X-ray photoelectron spectrum (XPS), transmission electron microscopy (TEM), Energy dispersive X-ray analysis (EDAX), and Matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry. Direct oxidation of dibenzothiophene (DBT) using O2 was performed by this reverse micellar catalyst with ∼100% selectivity in the oxidation of DBT to sulfone. By this catalyst, it could catalytically decrease sulfur level in diesel from 500 ppm to 1.0 ppm at ambient pressure and moderate temperature.

In this work, we have utilized the second-sphere coordination approach toward the construction of supramolecular inclusion solids Cl · 2H2O ⊂ [H2L1]0.5 · [CuCl4]0.5 (Crystal 1) and Cl ⊂ [H2L1] · [TeCl6]0.5 (Crystal 2). The chloride anions can be encapsulated inside the host assemblies formed by the diamine molecule (4,6-dimethyl-1,3-phenylene)bis(N,N-dibenzylmethane) (L1) and the metal complexes ([CuCl4]2− and [TeCl6]2−) via second-sphere coordination. The complexes have been structurally characterized by X-ray crystallography, indicating that weak C–H ··· Cl hydrogen-bonding synthons play a significant role in the construction of second-sphere coordination complexes. 2-D networks are formed in both complexes by the interconnection of 1-D networks through multiple C–H ··· Cl hydrogen-bonding interactions with [CuCl4]2− and [TeCl6]2−. The guest chlorides are encapsulated inside the host cages through N–H ··· Cl hydrogen bonds.

We have presented herein the utilization of second sphere coordination approach to construct supramolecular inclusion solids with varieties of guest molecules. Two distinct types of host frameworks were constructed by cobalt chloride anion ([CoCl4]2− or [Co2Cl6]2−) and diprotonated N-bidentate ligand L1 (N,N,N′,N′-tetra-p-methylbenzyl-ethylenediamine) or chloride anion-directed L1. The pillared double - layered host framework constructed by cobalt chloride anion ([CoCl4]2− or [Co2Cl6]2−) and chloride anion-directed L1 can encapsulate o-hydroxybenzaldehyde and p-hydroxybenzaldehyde molecules, leading to the formation of supramolecular inclusion solids: {[C7H6O2]1.5·[CH4O]0.5} ⊂ {[L1]2·4H+·2Cl−·[CoCl4]2−} (1) and {[C7H6O2]0.5·[CH4O]0.25} ⊂ {[L1]·2H+·Cl−·[Co2Cl6]0.52−} (2); whereas the channel-cave host framework constructed by [CoCl4]2− and L1 can include acetic acid molecules, leading to the formation of supramolecular inclusion solid [C2H4O2]2 ⊂ {[L1]·2H+·[CoCl4]2−} (3).

Reducing amplicon sizes has become a major strategy for analyzing degraded DNA typical of forensic samples. However, amplicon sizes in current mini-short tandem repeat-polymerase chain reaction (PCR) and mini-sequencing assays are still not suitable for analysis of severely degraded DNA. In this study, we present a multiplex typing method that couples ligase detection reaction with PCR that can be used to identify single nucleotide polymorphisms and small-scale insertion/deletions in a sample of severely fragmented DNA. This method adopts thermostable ligation for allele discrimination and subsequent PCR for signal enhancement. In this study, four polymorphic loci were used to assess the ability of this technique to discriminate alleles in an artificially degraded sample of DNA with fragment sizes

Second-sphere coordination refers to any intermolecular interaction with the ligands directly bound to the primary coordination sphere of a metal ion. In this article, we have successfully applied the second-sphere coordination approach in the construction of versatile host frameworks that can accommodate various guest molecules. We have used a family of bidentate flexible molecules as second-sphere ligands, and the tetrachlorometalate anion [MCl4]2– (where M = Cu, Co, Cd, Zn, and Hg) as the primary coordination sphere to synthesize new second sphere adducts. By introducing an alkyl spacer −(CH2)n– (n = 1, 2, 3, 4) to bibenzylamine (L0), the ligands L1, L2, L3, and L4 with higher degree of flexibility were synthesized. Different guest molecules such as alcohol, acetic acid, acrylic ester, or acetonitrile can be included in the host framework self-assembling diprotonated L1–L4 and [MCl4]2–, leading to a novel type of supramolecular assemblies: CH3CH2OH⊂[L2]2H+·[CuCl4]2– (2), CH3OH⊂[L3]2H+·[MCl4]2– (3), CH3...

Correction for ‘New promising lithium malonatoborate salts for high voltage lithium ion batteries’ by Xiao-Guang Sun et al., J. Mater. Chem. A, 2017, 5, 1233–1241.

We have applied crystal engineering as a tool to study the solid-state transformation from molecular salts to coordination complexes via mechanochemical dehydrochlorination reactions. The -(CH2)n- (n = 2, 3) alkyl chains were introduced into the bibenzylamine moiety to form the two nitrogen bases N,N,N',N'-tetrabenzylethylenediamine (L(1)) and N,N,N',N'-tetrabenzylpropydiamine (L(2)), which were self-assembled with tetrachlorometalates to form a series of supramolecular salts through second-sphere coordination. Single crystals of salts [L(1)]2H(+)·[CuCl4](2-)·solvent (1) and [L(2)]2H(+)·[XCl4](2-)·solvent (2-4; X = Cu, Hg, Zn) were obtained and their structures determined by single-crystal X-ray diffraction. The effect of different alkyl chains (two and three -CH2- units) on the solid-state reactivity showed that the chelating complexes resulting from the mechanochemical dehydrohalogenation reaction depend on the formation of quasi-chelating hydrogen-bonding salts. Quantum-mechanical calculations have been used to gain insight in this mechanochemical dehydrohalogenation reaction, demonstrating that not only is size matching between reactants is important but also conformational energies, intermolecular interactions, and the symmetry of frontier molecular orbitals play an important role.

To analyze the prevalence characteristics and influence factors of pneumoconiosis of workers exposed to dusts in an iron mine, to provide the base of preventive measures for pneumoconiosis of iron mine.The subjects of cohort study were all workers exposed to dusts for at least one year registered in an iron mine during 1960 to 1974, and followed-up to the end in 2003. The cases with pneumoconiosis were diagnosed by the local diagnosis group of pneumoconiosis, according to the national diagnostic criteria of pneumoconiosis. The risk factors were analyzed with Cox risk model.A total of 3647 miners were included in the cohort study and were followed up by 132 574.4 person years. There were 316 cases with pneumoconiosis, and the incidence of pneumoconiosis for a year was 0.24 per thousand. There were 274 cases (86.7%) with pneumoconiosis in workers exposed to dusts before 1960, the incidence of pneumoconiosis for a year was 0.40 per thousand, which was significantly higher than that (0.07 per thousand) of workers exposed to dusts after 1960. The average latency of pneumoconiosis was 26.0 +/- 7.3 years. The average durations of upgrade from stage 0(+) to I , I to II and II to III were 5.3 +/- 3.2, 6.6 +/- 5.2 and 11.3 +/- 5.0 years, respectively. However, 164 cases with pneumoconiosis were diagnosed after ceasing exposure to dusts for mean 8.3 years. The risk of pneumoconiosis in iron miners increased with exposure doses, and there was an obvious dose-effect relationship. The average cumulative exposure dose of cases with pneumoconiosis was 173.7 +/- 91.6 mg/m3 x y, which was significantly higher than that (112.1 +/- 64.8 mg/m3 x y) of workers without pneumoconiosis. Also the tuberculosis (HR = 5.9, P0.001) and smoking (HR = 1.7, P0.01) were the main risk factors.There was an obvious dose-effect relationship between the cumulative exposure dose and pneumoconiosis incidence. Tuberculosis and smoking were the main risk factors influencing the pneumoconiosis incidence.

To fabricate polyvinyl alcohol (PVA)/chitosan hybrid nanofibrous scaffolds owning the similar physiological structure of ECM, and to observe its biodegradation behavior in vivo and in vitro.(1) The PVA nanofibrous scaffold and PVA/chitosan hybrid nanofibrous scaffold were fabricated by electrospinning technique, and then they were crosslinked by glutaraldehyde vapor method. The morphology of both scaffolds was observed by scanning electron microscope (SEM). (2) Biodegradation experiment in vitro: the samples of two scaffolds with size of 2 cm x 2 cm were placed into phosphate-buffer saline (PBS) fluid under 37.0 degrees C water for incubation, and then they were dried to observe morphologic changes under SEM on post incubation day (PID) 3, 7, and 14. (3) Biodegradation experiment in vivo: 48 Wistar rats were divided into PVA group and PVA/chitosan group according to the random number table, with 24 rats in each group. PVA or PVA/chitosan nanofibrous scaffold was implanted into subcutaneous tissue on both sides of back in rats of both groups, with 4 scaffolds in each rat. The scaffold samples were harvested to observe morphologic changes with HE staining on post operation day (POD) 3, 7, 14, and 28.(1) After crosslinking, the surface of fibers in PVA and PVA/chitosan hybrid nanofibrous scaffolds were smooth, and the diameters of fibers were similar, ranging from 200 to 300 nm, with high porosity. (2) Biodegradation experiment in vitro showed that the morphologic changes in fiber was respectively swelling, dissolution, fusion in PVA nanofibrous scaffold on PID 3, 7, 14, and that in PVA/chitosan hybrid nanofibrous scaffold was respectively swelling, dissolution and fragmentation, and disappearance. (3) Biodegradation experiment in vivo showed that the morphologic changes in scaffold structure was respectively loosening, fuzziness of edges, degradation, and disappearance in PVA group and PVA/chitosan group on POD 3, 7, 14, 28.PVA/chitosan hybrid nanofibrous scaffolds can be prepared with electrospinning technique, and it has an appropriate biodegradation rate compatible with tissue reconstruction after crosslinking.

To study the effect of mining operations on the mental health of residents living in a mining area in Hubei province.Villagers (n = 93) living in the mining area were compared with a control group of residents (n = 101) in mental health status, and knowledge of environment and health. The mental health status of villagers was assessed using the Symptom Checklist 90 (SCL-90), State-Trait Anxiety Inventory (STAI); The knowledge of environment and health was evaluated using a self-designed questionnaire. The urine and hair samples were collected from some subjects. The lead, cadmium, arsenic, copper and zinc contents were detected as well as the total protein, NAG, d-ALA in the urine.The occurrence rate of lead, cadmium, arsenic exposure symptoms was significantly higher in the exposed group than in the control group. The urine cadmium, the hair cadmium, the hair arsenic and hair lead were significantly higher in the exposed group than in the control group (P0.05). The positive symptom detection rate of SCL-90 in the exposed group was 8.60% compared with 0.99% of the control group. For the SCL-90, the total scale, somatization, obsessive-compulsive, interpersonal sensitivity, depression, anxiety, hostility, paranoid ideation, psychoticism, other symptom in the exposed groups were significantly higher than those in the control group (P0.05), indicating the status of the psychological hygiene of the exposed group was worse than the control group. The total S-AI (anxiety) score and the sex-specific value in the exposed group were higher than the control group (P0.05, P0.01), which showed that the anxiety of the exposed group was more evident. The total T-AI score and the sex-specific value in women of the exposed group were significantly higher than the control group (P0.01), showing that the anxiety were more significant in the exposed group, especially the women of the exposed group.The mental health status of the residents who living in a mining area is affected and they have a higher S-AI and T-AI scale than those living a non-mining area.

To investigate the polymorphism of the TPH gene T3792A locus in Han ethnic group of north China and its application value in forensic science.The polymorphism of T3792A locus of the TPH gene was analyzed by the ASPCR of blood samples from 173 unrelated individuals of north Chinese Han population.The distribution of the T3792A locus polymorphism of the TPH gene in Han ethnic group of north China followed the Hardy-Weinberg law, with the allele A and T gene frequency of 0.486 and 0.514, respectively.The TPH gene T3792A locus shows a very good genetic polymorphism, and may be applied to individual identification and paternity testing.

Purpose: To characterize the expression of sphingosine kinase-1 (SPHK1) in human astrocytomas and to investigate the association between SPHK1 expression and progression of astrocytomas. Experimental Design: The expression of SPHK1 in normal human astrocytes, astrocytoma cell lines, and four pairs of matched astrocytoma tissues and their adjacent normal brain tissues were detected by quantitative reverse transcription-PCR and Western blot. In addition, SPHK1 protein expression was examined in 243 cases of histologically characterized astrocytomas by immunohistochemistry. Statistical analyses were applied to test for prognostic and diagnostic associations. Results: SPHK1 in astrocytoma cell lines was elevated at both mRNA and protein levels, and the SPHK1 mRNA and protein were significantly up-regulated by up to 6.8- and 40-fold, respectively, in primary astrocytomas compared with those in the adjacent noncancerous brain tissues. Immunohistochemical analysis showed that 100 of 243 (41.2%) paraffin-embedded archival astrocytoma biopsies exhibited high expression of SPHK1. Statistical analysis suggested that the up-regulation of SPHK1 was significantly correlated with the histologic grade of astrocytoma (P = 0.000) and that patients with high SPHK1 level exhibited shorter survival time (P < 0.001). Multivariate analysis revealed that SPHK1 up-regulation might be an independent prognostic indicator for the survival of patients with astrocytoma. Conclusions: SPHK1 might represent a novel and useful prognostic marker for astrocytoma and play a role during the development and progression of the disease.

To study the distribution of the tryptophan hydroxylase (TPH) gene-T457C locus polymorphism in Han ethnic group in northern China and to find its applicable value in forensic science.Genomic DNA samples, extracted from 180 unrelated individuals in northern Chinese Han population, were analyzed by PCR-RFLP.The discrimination power (DP) value and the power of exclusion (PE) value of the TPH gene-T457C locus were 0.624 and 0.187, respectively. The allele frequency showed significant difference from that of French people (P=0.04).Polymorphism of the TPH gene-T457C locus could show ethnic and regional differences. It has a potential to be used in forensic science.

To evaluate the influence of different types of posts and cores on the final color of the IPS-Emperss 2 crown.Five types of posts and cores (Cerapost with Empress cosmo, Cerapost with composite resin, gilded Ni-Cr alloy, gold alloy and Ni-Cr alloy) were made. The shifts in color of three points of IPS-Empress 2 crown surface (cervical, middle and incisal) with different posts and cores was measured with a spectroradiometer (PR-650).The L* a* b* values of zirconium oxide and gilded Ni-Cr alloy posts and cores with ceramic crown were the highest. The L* a* values of zirconium oxide posts composite cores were higher while the b* values were lower. The L* a* b* values of Ni-Cr alloy were lower than that of gold alloy and were the lowest.In combination with IPS-Empress 2 crown, zirconium oxide posts are suitable for routine use in the anterior dentition, and gilded Ni-Cr alloy and gold alloy posts and cores can be recommended for clinical practice. Ni-Cr alloy posts and cores can not be recommended for clinical practice.

To investigate the effects of luting agent on the final color of glass infiltrated alumina ceramic restorations.12 plate-shaped specimens with 12.5 mm in diameter and 0.5 mm thickness were fabricated from GI-II (color IG2). Vitadur alpha veneering porcelain (color A2) with 1.0 mm thickness was fired to GI- II glass/alumina composite. 12 plate-shaped background specimens simulating the metal alloy post-and-core 12.5 mm in diameter and 2 mm thickness were also made from Ni-Cr alloy. All-ceramic specimens were luted to the metal alloy by Zinc Phosphate cement, glass ionomer cement and composite resin. The color shifts of the specimens were measured by colorimeter.Luting agents had effect on the final color of restorations. The influence of composite resin was least, followed by glass ionomer cement and Zinc Phosphate cement. The color difference between with and without Zinc Phosphate cement could be identified by the eye.To reduce the effect of luting agents, composite resin is recommended to all-ceramic restorations' adhesion.

To investigate the main diseases jeopardizing the health of the iron miners and to explore the relationship between dust exposure and malignancies as well as other diseases.A retrospective study with a cohort of 7,469 workers employed between January 1, 1972 and December 31, 1974 in Daye Iron Ore Mine Co. in Hubei Province was conducted. Standardized mortality ratio (SMR) was calculated for the main causes of death using Chinese national mortality rates for reference.All subjects were followed up through December 31, 2003 with an accumulation of 199, 108.0 person years. A total of 1,752 workers died. The cumulative mortality was 23.5%. The cancers, cerebrovascular diseases, non-malignant respiratory diseases and cardiovascular diseases were main diseases that threatened workers' life span. The SMR for all subjects was a little higher than expected based on the Chinese national mortality rates. The diseases causing the significantly higher death rate were the nasopharynx cancer, liver cancer, lung cancer, pneumoconiosis and accident with SMR 1.84, 1.51, 1.83, 14.94 and 1.25 respectively. Increased mortality was observed among dust-exposed workers in the cohort. The cumulative mortality from all causes such as stomach cancer, lung cancer, nonmalignant respiratory diseases, cardiovascular diseases and accident in dust exposed workers were significantly increased compared with those in non-exposure workers with RR 1.35, 1.83, 1.61, 2.27, 1.34 and 1.69 respectively.The risk factors especially dust exposure affect the health and lifespan of the iron mine workers.

Porous α-Fe2O3 nanowires are synthesized by a simple wet chemical method with a precursor of peroxyacetyl nitrate (PAN), and α-Fe2O3 nanoparticles are also synthesized in the same way except for the addition of PAN. Gas sensors are fabricated by coating the samples on ceramic tubes with Au signal electrodes and Ni-Cr heaters. A sensing investigation reveals that the porous α-Fe2O3 nanowires have a higher sensitivity compared to α-Fe2O3 nanoparticles at 260°C. The corresponding sensor response (Ra/Rg) is 18.2 at the maximum to 100 ppm acetone, and the response and recovery times are about 8 and 12 s, respectively. The porous and one-dimensional nanostructures of the porous α-Fe2O3 nanowires benefit for the gas-absorption and electrical-signal-transfer, and thus improve the sensor sensitivity consequentially.