Search

A dynamic mechanical model is proposed to describe the complexing actions of all the rolls on the ring during the ultra-large radial-axial ring rolling (RARR) process with four guide rolls. Based on the model, the calculation models for bending moment and normal stress at any section of the ring are deduced by force method. If the maximum section bending normal stress exceeds the yield stress of the ring materials, the ring will be distorted thus leading to the instability of the RARR process. According to this, a plastic instability criterion for the ultra-large RARR process with four guide rolls is developed, based on which a mathematical model to calculate the critical guide force for avoiding plastic instability of ring is obtained. The influence rule of the position of guide roll on the dangerous ring section of plastic instability is revealed, from which it is found the dangerous ring section mainly appears at the radial and axial deformation regions and the contact positions of the guide rolls and ring. The optimized layout of guide roll around the ring in favor of stability is determined to be about α1=61° and α2=119°. The plastic instability criterion is proven to be reliable from the aspects of the critical guide force, the section bending moment and normal stress and the dangerous ring section of plastic instability. Intelligent simulation case studies for the RARR process of ultra-large aluminum alloy ring indicate that the stable forming of the process can be effectively realized by regulating the guide force based on the plastic instability criterion. This work could provide a valuable guidance for the control of guide rolls and the optimization of the ultra-large RARR process with four guide rolls.

Objective To propose the suitable diameter of calculus debris produced during flexible ureteroscopy lithotripsy (fURL). Methods A glass tube was used to simulate the stone excretion process during Furl. Different stone diameters (0.50–1.00 mm, 0.25–0.50 mm, and 0.10–0.25 mm) with three sizes of flexible ureteroscopy (fURS) (Fr7.5, Fr8.7, and Fr9.9) and ureteral access sheath (UAS) (12/14Fr) with or without negative pressure suction were employed in the experiment. The intraoperative calculi excretion (ICE) was recorded according to the stones discharged from the gap between Furs and UAS. Results The ICE raised significantly in thinner fURS and UAS due to the smaller ratio of endoscope-sheath diameter (RESD). The gravel size ≤ 0.25 mm was conducive to drainage with traditional UAS, while using fURS with negative-pressure UAS could significantly improve ICE. The gravel size ≤ 0.5 mm was conducive to expulsion. Conclusion We clarify that ICE during ureteroscopy relates to RESD and negative pressure suction. The proper size of the stone fragment is critical in ensuring the expulsion during fURL, ≤ 0.25 mm in traditional UAS and ≤ 0.50 mm in negative-pressure UAS, respectively.

Considering the special requirements for damping materials in the field of building isolation and vibration control, this research aims to improve the mechanical and damping properties of nitrile butadiene rubber (NBR, ACN content: 36–42%)-based matrix material by blending four kinds of minimal particles. Carbon black, light silicon dioxide, graphite powder and AO-80 were blended with the matrix material. Orthogonal test was designed and dynamic mechanical analysis test was carried out. The results were evaluated by multiple indicators, including the glass transition temperature (Tg), the peak value of loss factor (ηmax), the width of large damping range in which loss factor is larger than 0.5 (∆T0.5) and the integral area of Loss factor-Temperature (TA). The results showed that the NBR modified by minimal particles could effectively improve the damping properties of the matrix material and made the Tg closer to the service temperature of buildings. Graphite powder could significantly increase the ηmax, and effectively broaden the ∆T0.5. AO-80 could significantly increase the ηmax and TA value. In addition, the optimal scheme was determined by Analytic Hierarchy Process (AHP), with carbon black: light SiO2: graphite powder: AO-80: matrix material = 15: 30: 40: 50: 100.

Background and objective: Congenital hypothyroidism (CH) is the most common and preventable neonatal endocrine disorder, with an incidence of 1 in 2000–3000 newborns worldwide, and 1 in 2400 in China. However, the genetic causes of congenital hypothyroidism, in particular due to thyroid dysgenesis (TD) remain largely unknown. Previous study indicated that JAG1 is a novel susceptibility gene for congenital thyroid defects. To explore the association between JAG1 and CH, we screened JAG1 variants in a large cohort of 813 CH patients. Methods We performed genetic analysis of JAG1 using next-generation sequencing in 813 CH cases. After data analysis and verification by Sanger sequencing, we identified 10 pathogenic variants in 25 patients. And then we performed further genetic analysis targeting 20 CH related genes in these 25 JAG1 variant carriers. The pathogenicity of variants were assessed by bioinformatics softwares, protein sequence conservation analysis, and hydrophobic analysis. Results We identified 10 pathogenic missense mutations (p.V45L, p.V272I, p.P552L, p.G610E, p.G852D, p.A891T, p.E1030K, p.R1060W, p.A1131T, p.P1174L) carried by 25 patients, the mutation rate of JAG1 in CH was 3.08%. Among these 25 patients, 16 with 1 variant, 6 with 2 variants, and the other 3 with 3 variants. Our findings indicated that JAG1 variants confer genetic susceptibility to both TD and DH, but with different inheritance models. JAG1 variants lead to TD mainly through monogenic model, while for DH cases, both monogenic mechanisms and oligogenic mechanisms play a pivotal role. Oligogenicity may contribute to the disease severity of DH. Conclusion JAG1 is one of the overlap of genetic aetiologies in TD and DH, with the detection rate in CH in China was 3.08%. The comparation between oligogenic group and monogenic group revealed that CH may exhibit a gene dosage effect. Patients with the same JAG1 mutation demonstrate a broad spectrum of clinical phenotypes, indicating the mechanisms involved in its phenotypic heterogeneity is complex.

Background X-linked hyper IgM syndromes (X-HIGM) and autosomal recessive hyper IgE syndromes (HIES) are rare primary immunodeficiency diseases, characterized by recurrent infections due to the impairment in immune system. This study was aimed to investigate genotype-phenotype association and reveal the novel likely pathogenic mutations in CD40L and DOCK8 responsible to patients with X-HIGM and HIES respectively. Methods Whole exome sequencing (WES) and Sanger sequencing were performed to identify and verify the likely pathogenic mutations in the two families. Results A novel hemizygous mutation for CD40L in exon 2 (c.257delA) was identified in the first proband resulting in the substitution of glycine for glutamic acid at 86 codon of the protein causing the early termination of translation at downstream codon 9 (p.E86Gfs*9). Sanger sequencing verified that the variant was inherited from his mother. The second proband carried two novel compound heterozygous mutations in DOCK8, one at exon 14, c.1546C > G inherited from his father, another at exon 41, c.5355 + 6C > T(splicing) from his mother. Conclusion This study extends our knowledge to pathogenetic mutations spectrum of CD40L and DOCK8 which is helpful for accelerating prenatal diagnosis of X-HIGM and HIES and promoting timely treatment of patients.

The low transfer efficiency and high recombination loss of photo-induced carriers in TiO2 are significant issues that hinder its photocatalytic activity. Herein, TiO2 nanoparticles (∼5 nm) were loaded on MnO2 nanosheets (40-60 nm) to form TiO2-MnO2 nanostructured heterojunction (0D-2D nanostructure unit), possessing a high specific surface area. The separation/transfer efficiency of photocarriers and the solar absorptivity of TiO2-MnO2 were improved, thus enhancing solar energy conversion efficiency. The enhanced transfer efficiency of carriers is associated with the 2D network of MnO2 and abundant oxygen vacancies serving as media for electron transport. The enhanced visible absorption and reduced recombination should be attributed to the narrowed bandgap and modified energy band structure. The photocurrent of TiO2-MnO2 increased obviously and the H2 production rate increased to 0.38 mmol g-1 h-1, compared with that of pure TiO2 (0.25 mmol g-1 h-1). The enhanced photocatalytic properties are also associated with the excellent water oxidation kinetics caused by MnO2 nanosheets.

Advanced electrocatalysts for complete oxidation of ethylene glycol (EG) in direct EG fuel cells are strongly desired owing to the higher energy efficiency. Herein, Pd-PdSe heterostructural nanosheets (Pd-PdSe HNSs) have been successfully fabricated via a one-step approach. These Pd-PdSe HNSs feature unique electronic and geometrical structures, in which unconventional p-d hybridization interactions and tensile strain effect co-exist. Compared with commercial Pd/C and Pd NSs catalysts, Pd-PdSe HNSs display 5.5 (6.6) and 2.5 (2.6) fold enhancement of specific (mass) activity for the EG oxidation reaction (EGOR). Especially, the optimum C1 pathway selectivity of Pd-PdSe HNSs reaches 44.3 %, illustrating the superior C-C bond cleavage ability. Electrochemical in situ FTIR spectroscopy and theoretical calculations demonstrate that the extraordinary p-d hybridization interaction and tensile strain effect could effectively reduce the activation energy of C-C bond breaking and accelerate CO* oxidation, boosting the complete oxidation of EG and improving the catalytic performance.

Objective: We aimed to study the types and characteristics of TUBB1 mutations in a large Chinese cohort with congenital hypothyroidism (CH) and thyroid dysgenesis (TD). Methods: Mutation of the entire coding region of TUBB1 was analysed by Sanger sequencing in 289 children with CH and TD from China. Functional studies were further used to identify the effect of novel mutations on thyroid cells. Results: Among the 289 children with CH and TD, 4 (1.4%) had a c.952C>T(p.R318W) heterozygous mutation in TUBB1, resulting in a change from tryptophan to arginine at codon 318 of the TUBB1 protein. Functional studies indicated that the p.R318W mutant decreased TUBB1 expression and inhibited cell proliferation in a human thyroid cell line. Conclusions: A novel heterozygous missense mutation of TUBB1 in children with CH and TD was identified first in China, laying the foundations to expand the genotype-phenotype spectrum of TD.

Mutations in DUOX2 are the frequent cause of congenital hypothyroidism (CH), a common neonatal metabolic disorder characterized by great phenotypic variability. CH can be traditionally subclassified into two subtypes: thyroid dysgenesis (TD) and thyroid dyshormonogenesis. The objectives of this study were to analyze the genetic data of two familial CH cases, to elucidate the pathogenesis from the perspective of genetics and to review and summarize the previous findings. Targeted regions sequencing (TRS) technology covering all exons and intron-exon boundaries of 35 known and potential CH-related candidate target genes in combination with Sanger sequencing were performed to identify the likely pathogenic mutations of the six patients with familial CH. In family 1, two DUOX2 missense mutations, namely, c.1060C>T/p.R354W in exon 10 and c.3200C>T/p.S1067L in exon 25, were found. Patient 1 (P1), P2 and P3 were transient CH (TCH) patients with eutopic thyroid glands of normal size and function. In family 2, only the mutation c.3200C>T/p.S1067L was identified. P4, P5, and P6 were diagnosed with permanent CH (PCH), which requires lifelong levothyroxine (L-T4) treatment. Furthermore, both P4 and P5 harbored properly located thyroid glands, whereas P6 had a mildly reduced gland. P1, P3, P6, and other family members carrying monoallelic or biallelic DUOX2 mutations showed no obvious abnormal clinical symptoms or signs, while P2, P4, and P5 showed umbilical hernias. The present study suggests that the phenotypic features resulting from DUOX2 mutations vary greatly. The p.R354W and p.S1067L alterations or the combination of the two alterations in DUOX2 are probably only predisposing to CH and DUOX2 may be involved in the morphogenesis of the human thyroid gland. Simultaneously, the compensation of DUOX1 for the loss of DUOX2, undetectable pathogenic mutations, the effects of environmental factors, epigenetic mechanisms and the involvement of multiple genes cannot be excluded in the explanation of these genetic results.

To enhance the piezoelectric responses, Ba0.85Ca0.15Zr0.1Ti0.9O3 (BCZT) ceramics were fabricated by a sol–gel method in various sintering atmospheres. The effects of oxygen partial pressure on the microstructure and electrical properties of BCZT ceramics were systematically investigated. The samples sintered in air, O2 and N2 are the coexistence of the orthorhombic (O)-tetragonal (T) phase at room temperature. The phase transition temperature of the O–T phase of BCZT samples sintered in air, O2 and N2 is gradually closer to room temperature. The results of EDS, XPS and the activation energy confirm the significant effect of oxygen sintering atmosphere. BCZT samples sintered in oxygen atmosphere show excellent ferroelectricity (2Pr = 31.62 μC/cm2, 2EC = 3.46 kV/cm) and significantly enhanced piezoelectricity (d33 = 604.3 pC/N, d 33 * = 647.5 pm/V and kp = 58%), resulting from the minimum oxygen vacancy, the phase transition temperature of O–T closer to room temperature and dense microstructure. These results demonstrate that adjusting oxygen partial pressure in sintering is an effective way to enhance the piezoelectric responses of BCZT ceramics.

Thyroid dysgenesis (TD) accounts for 80% cases of congenital hypothyroidism, which is the most common neonatal disorder. Until now, the gene mutations have been reported associated with TD can only account for 5% cases, suggesting the genetic heterogeneity of the pathology. Nicotinamide nucleotide transhydrogenase (NNT) plays a crucial role in regulating redox homeostasis, patients carrying NNT mutations have been described with a clinical phenotype of hypothyroidism. As TD risk is increased in the context of several syndromes and redox homeostasis is vital for thyroid development and function, NNT might be a candidate gene involved in syndromic TD. Therefore, we performed target sequencing (TS) in 289 TD patients for causative mutations in NNT and conducted functional analysis of the gene mutations. TS and Sanger sequence were used to screen the novel mutations. For functional analysis, we performed western blot, measurement of NADPH/NADPtotal and H2 O2 generation, cell proliferation, and wounding healing assay. As a result, three presumably pathogenic mutations (c.811G > A, p.Ala271Ser; c.2078G > A, p.Arg693His; and c.2581G > A, p.Val861Met) in NNT had been identified. Our results showed the damaging effect of NNT mutations on stability and catalytic activity of proteins and redox balance of cells. In conclusion, our findings provided novel insights into the role of the NNT isotype in thyroid physiopathology and broaden the spectrum of pathogenic genes associated with TD. However, the pathogenic mechanism of NNT in TD is still need to be investigated in further study.

The low transfer efficiency and high recombination loss of photo-induced carriers in TiO2 are significant issues that hinder its photocatalytic activity. Herein, TiO2 nanoparticles (∼5 nm) were loaded on MnO2 nanosheets (40-60 nm) to form TiO2-MnO2 nanostructured heterojunction (0D-2D nanostructure unit), possessing a high specific surface area. The separation/transfer efficiency of photocarriers and the solar absorptivity of TiO2-MnO2 were improved, thus enhancing solar energy conversion efficiency. The enhanced transfer efficiency of carriers is associated with the 2D network of MnO2 and abundant oxygen vacancies serving as media for electron transport. The enhanced visible absorption and reduced recombination should be attributed to the narrowed bandgap and modified energy band structure. The photocurrent of TiO2-MnO2 increased obviously and the H2 production rate increased to 0.38 mmol g-1 h-1, compared with that of pure TiO2 (0.25 mmol g-1 h-1). The enhanced photocatalytic properties are also associated with the excellent water oxidation kinetics caused by MnO2 nanosheets.

The cast preformed forming process (CPFP) is increasingly considered and applied in the metal forming industries due to its short process, low cost, and environmental friendliness, especially in the aerospace field. However, how to establish a unified model of a non-uniform as-cast billet depicting the flow stress and microstructure evolution behaviors during hot working is the key to microstructure prediction and parameter optimization of the CPFP. In this work, hot compression tests are performed using a non-uniform as-cast 42CrMo billet at 1123–1423 K and 0.01–1 s−1. The effect laws of the non-uniform state of the as-cast billet with different initial grain sizes on the flow stress and microstructure are revealed deeply. Based on experimental results, a unified model of flow stress and grain size evolutions is developed by the internal variable modeling method. Verified results show that the model can well describe the responses of the flow stress and microstructure to deformation conditions and initial grain sizes. To further evaluate its reliability, the unified model is applied to FE simulation of the cast preformed ring rolling process. The predictions of the rolling force and grain size indicate that it could well describe the flow stress and microstructure evolutions during the process. Keywords: Cast preformed forming process, Flow stress, Grain size, Non-uniform as-cast 42CrMo billet, Ring rolling, Unified model

Bi0.9La0.1FeO3 (short for BLFO) ceramics was fabricated by conventional solid-state reaction and microwave sintering. Effects of microwave sintering temperature on microstructure, electric and magnetic properties have been systematically investigated. The XRD results indicate that BLFO ceramics sintered at 800 °C and 820 °C are single rhombohedral distortion perovskite phase, and there is small amount of secondary phase (Bi2Fe4O9) in the ceramic sample sintered at 780 °C. As microwave sintering temperature rises, the densification of BLFO ceramics enhances and the grain size increases, but the homogeneity of grain becomes worse. Microwave sintering temperature has little effect on room-temperature dielectric constant. The leakage current density decreases with the rise of sintering temperature, which is closely related to enhanced densification. The leakage mechanism of BLFO ceramics changes from bulk-limited Poole-Frenkel emission to space-charge-limited bulk conduction as sintering temperature rises. The remnant polarization of BLFO ceramics sintered at 820 °C is much higher than that of the samples sintered at 800 °C and 780 °C, and the coercive electric field changes little with sintering temperature. The results indicate the higher sintering temperature is benefit for the ferroelectricity of BLFO ceramics. The magnetic hysteresis loops of BLFO ceramics indicate that the ceramic samples sintered at 800 °C and 820 °C show a typical ferromagnetic behavior at room temperature. Compared with BLFO ceramics sintered at 800 °C, the spontaneous magnetization and saturation magnetization of BLFO ceramics sintered at 820 °C are higher, and its remnant magnetization and coercive magnetic field are lower.

(Ca1−xSrx)3(Ti1−yMny)2O7 (CSTMO) ceramics with hybrid improper ferroelectricity were prepared by conventional solid-state reaction method. Effect of Sr2+ and Mn4+ contents on microstructure, dielectric and ferroelectric properties have been systematically investigated. The XRD results show that CSTMO ceramics is single phase with orthorhombic structure. The lattice constants and average grain size increase with the increasing of Sr2+ content and decrease with the increasing of Mn4+ content. The introduction of Mn4+ deteriorates the densification of CSTMO ceramics to some extent, and the substitution of Sr2+ with higher content can improve the densification by promoting a rapid interdiffusion movement via grain-boundary. (Ca0.8Sr0.2)3(Ti0.9Mn0.1)2O7 ceramics present the highest dielectric constant and dielectric loss, while the dielectric loss of (Ca0.8Sr0.2)3(Ti0.95Mn0.05)2O7 ceramics has a significant reduction. The leakage current of CSTMO ceramics decreases with the increasing of Sr2+ and Mn4+ content. The leakage behavior suggests that the Ohmic conduction and Schottky emission dominate the leakage current of CSTMO ceramics. Moreover, the remnant polarization decreases with the increasing of Sr2+ because of its suppression for the rotating and tilting angle (a−a−c+) of oxygen octahedron. And the electrical polarization decreases with the increasing of Mn4+ content due to the instability of MnO6 rotation.

The BiFeO3 (BFO) thin films were prepared on Pt(111)TiO2/SiO2/Si substrates by the sol-gel method at different annealing temperatures. The crystalline structure and domain configuration of BFO film...

Magnetoelectric multiferroic materials have attracted great attention due to their intriguing properties and potential applications. In this paper, (1 − x) Co0.8Cu0.2Fe2O4-xBa0.6Sr0.4TiO3 (x = 0, 0.4, 0.45, 0.475, 0.5, 0.525, 0.55, 1) composites were prepared by the conventional solid-state method combining with a sol–gel process. The effect of x on the microstructure, dielectric and multiferroic properties has been systematically investigated and discussed. The results confirm pure bi-phase Co0.8Cu0.2Fe2O4 and Ba0.6Sr0.4TiO3 composites except for slight impurity phases, which are indexed as BaCuO2/BaFe12O19. All the samples show uniform and relatively smooth surfaces with the mean grain size of ∼ 1.5 μm which decreases slightly with the increase of x, demonstrating the moderating effect of the ferroelectric phase on the grain size. The dielectric constant shows intense dependence on the components and the highest value is obtained when x = 0.525. The ferroelectric loops demonstrate that the coercive field and remnant polarization of the sample x = 0.525 are higher than other samples except for the pure Ba0.6Sr0.4TiO3 specimen at room temperature. The Co0.8Cu0.2Fe2O4 shows better magnetic properties and the performance of magnetization decreases with the decrease of Ba0.6Sr0.4TiO3; meanwhile, the impurity phase and inhomogeneous structure have certain influences on the magnetic properties.

In this work, four new dry water fire extinguishing agents (FEAs) were prepared by hydrophobic SiO2 and aqueous solution under certain conditions. The dry water FEAs were developed and we conducted two types of fire extinguishing experiments (i.e., class A solid fire and class B liquid fire test). Thermocouples and a color video camera were used to measure burning temperature and record the fire extinguishing process. Results indicate that the new dry water FEAs have the ability to extinguish A, B and C fires, and have a better cooling effect than dry powder FEA. It is noted, compared with traditional FEAs, that dry water FEAs have the advantages of high efficiency and high speed, and have a potential application prospect.

Purpose The objectives of this study were to analyze the distribution of dual oxidase (DUOX) system genes (containing DUOX2, DUOX1, DUOXA2, and DUOXA1) variants in children with congenital hypothyroidism (CH) and their phenotypes. Methods Target region sequencing technology was performed on DUOX system genes among 606 CH subjects covering all the exon and intron regions. Detailed clinical data were collected for statistical analysis. Results A total of 95 suspected pathogenic variants were detected in the DUOX system genes, showing a 39.11% rate in variant carrying (237/606). DUOX2 had the highest rate in this study. There were statistical differences in maximum adjusted dose and current dose of levothyroxine between the DUOX system genes nonmutated group with the mutated group (both Ps Conclusions Our results showed the high variation rate of DUOX2 in the DUOX system genes among Chinese CH patients. The complex genotype-phenotype relationship of DUOX system genes broadened the understanding of CH phenotype spectrum.

To overcome the recombination issue of photocarriers, TiO2 quantum dots (QDs, nanoparticles in a few nanometers) were used to form heterojunctions with graphene oxide nanosheets. This combination has significantly enhanced the photocatalytic activity by providing more active reaction sites at the nanoscale surface and suppressing photocarrier recombination through fast separating the photocarriers by the internal electric field in the TiO2/graphene oxide heterojunctions. The enhancement in photocatalytic activity has been evidenced by the improved hydrogen generation rate in photoelectrochemical water splitting, about 30% higher than that of bare TiO2 QDs in the same situation. Moreover, the TiO2/graphene oxide composite also exhibits a lower flat band potential, which means a higher reducing potential of photo-excited electrons.

Introduction: Thyroid dysgenesis (TD) is the main cause of congenital hypothyroidism (CH), affecting nearly 1 in 2000–3000 newborns worldwide, as the most common neonatal endocrine disorder. Paired box gene 8 ( PAX8 ), expressed during all stages of thyroid follicular cell, plays a key role in thyroid morphogenesis by a complex regulatory network. In conclusion, the genetic mechanism of PAX8 mutant in TD is still ambiguous; therefore, further research is needed. Material and methods: Blood samples were collected from 289 TD patients in Shandong Province, China. Genomic DNA was extracted from peripheral blood. All the exons of PAX8 along with their exon-intro boundaries were amplified by PCR and analysed by Sanger sequencing. Results: We identified three novel PAX8 nonsense mutations in three patients by sequence analysis of PAX8 : Patient 1 (c.285C>G, p.Tyr95Ter), Patient 2 (c.747T>G, p.Tyr249Ter), and Patient 3 (c.786C>A, p.Tyr262Ter). All the three patients carrying PAX8 variants had obvious clinical phenotypes of thyroid anomaly, such as hypoplasia and athyreosis. Conclusion: We conducted the largest worldwide PAX8 mutation screening so far in TD patients. Three presumably pathogenic PAX8 mutations were detected in 289 TD cases for the first time, showing the mutation rate of PAX8 is 1.04% in Chinese TD patients. In addition, our study expands the gene mutation spectrum of TD.

The band structures, density of states and optical properties of trigonal and hexagonal structures of BiFeO3 (BFO) were calculated by density functional theory (DFT) pseudo-potential plane-wave met...

Sparrow search algorithm has good global search performance, but there is still a probability of falling into local optimum. In order to optimize the algorithm, K-means is proposed to make the population evenly distributed and improve the efficiency at the beginning. Then, the sine-cosine search and adaptive local search strategies are introduced to reduce the probability of falling into the local optimum in the middle and late stages, so that the optimal solution can be obtained easily. Finally, the two strategies are discussed and applied to SVM parameter optimization. The UCI dataset classification results show that the algorithm with the two strategies is suitable for SVM parameter optimization, and the algorithm with sine-cosine search has better optimization ability and stability.

To overcome the recombination issue of photocarriers, TiO2 quantum dots (QDs, nanoparticles in a few nanometers) were used to form heterojunctions with graphene oxide nanosheets. This combination has significantly enhanced the photocatalytic activity by providing more active reaction sites at the nanoscale surface and suppressing photocarrier recombination through fast separating the photocarriers by the internal electric field in the TO2/graphene oxide heterojunctions. The enhancement in photocatalytic activity has been evidenced by the improved hydrogen generation rate in photoelectrochemical water splitting, which is about 30% higher than that of bare TiO2 QDs in the same situation. Moreover, the TiO2/graphene oxide composite exhibits a lower flat band potential, which means a higher reducing potential of photo-excited electrons.

Natural products sourcing chemical reference substances (NPSCRSs) are widely used in the analysis industry to determine the content and quality of food and drug products. Chromatographic techniques have been traditionally used to determine the purity of chemical reference substances (CRSs). However, the uncertainty values of NPSCRSs purity are rarely measured due to the chemical complexity of natural products and the diversity of instrument influencing factors. Recently, differential scanning calorimetry (DSC) technique has been proved to be able to detect the purity of CRSs, but its adaptability for NPSCRSs is rarely researched. Herein, a HPLC-DSC combined method was developed for the purity calibration and uncertainty measurement of 20 NPSCRS samples. As a result, the value of “purity ± uncertainty” was suggested to represent the quantitative result for purity measurement of NPSCRSs. Among four influence factors of HPLC analysis, the influence of peak area was first proposed as the source of uncertainty, and the uncertainty caused by the wavelength was simplified to a five wavelength-based method. As for DSC method using for purity determination of NPSCRSs, it could be used as an alternative and complementary method to verify the purity of a NPSCRS that is more than 98% because of its advantage of practicality, speed, reproducibility, no corresponding reference standard requirement, and no sample preparation is required. Note that, DSC method is not appropriate if the compound lacks standard melting peak, decomposes in the defined temperature range, or exhibits other thermal event (s) which interfere with the melting point of the compound.

Background Idiopathic infantile nystagmus (IIN) is a high genetically heterogeneous ophthalmic disease and is often associated with pathogenic mutations in FRMD7 and GPR143, respectively. Idiopathic infantile nystagmus manifests as involuntary periodic rhythmic oscillation of the eyes in the very early life, which decreases visual acuity and affects the quality of life. Objective and Methods The aim of our study was to reveal a possible pathogenic variant through the investigation of a Chinese Han family with IIN with an implementation of a next‐generation sequencing method. Isolated DNA analysis was followed by Sanger sequencing validation. We also performed the detailed ophthalmological examination of family members. Results We identified a novel frameshift variant in FRMD7 (NM_194277.2: c.1419_1422dup, p.Tyr475fs), which leads to a frameshift mutation since tyrosine (Tyr) at 475 codon of FRMD7 protein (p.Tyr475fs) and co‐segregates with IIN phenotype in this family. Conclusions We found a novel frameshift FRMD7 variant in a Chinese Han family, which may be causative variant for IIN and can further enrich the mutation spectrum and uncover the etiology of IIN.

Spontaneous combustion of coal is one of the major hazards threatening production safety during longwall mining. Mining-induced voids, which provide passages for air leakage, are the key factor triggering spontaneous combustion of coal in longwall goafs. In this study, a comprehensive method, which combined pressure balance, grouting injection, and filling fissures, was proposed to prevent spontaneous combustion of coal in longwall goafs with complex air leakage. Field engineering practice was carried out in Sitai Coal Mine in China. The results demonstrated that with the application of the proposed method, in the working face, the concentration of CO was decreased from 31ppm to 0 and the air leakage quantity was decreased from 261 to below 80 m3min-1. The gas samples analysis from the gob areas also indicated that concentrations of O2 and CO were successively decreased, indicating that the risk of spontaneous combustion of coal in goafs was eliminated. The above mentioned analysis indicates that, the method proposed in this study is useful and efficient. Successful application of this technology could provide reference for the treatment of other coal mines.

Ferroelectric nanowires have attracted great attention due to their excellent physical properties. We report the domain structure, ferroelectric, piezoelectric, and conductive properties of bismuth ferrite (BFO, short for BiFeO3) nanowires characterized by scanning probe microscopy (SPM). The X-ray diffraction (XRD) pattern presents single phase BFO without other obvious impurities. The piezoresponse force microscopy (PFM) results indicate that the nanowires possess a multidomain configuration, and the maximum piezoelectric coefficient (d33) of single BFO nanowire is 22.21 pm/V. Poling experiments and local switching spectroscopy piezoresponse force microscopy (SS-PFM) demonstrate that there is sufficient polarization switching behavior and obvious piezoelectric properties in BFO nanowires. The conducting atomic force microscopy (C-AFM) results show that the current is just hundreds of pA at 8 V. These lay the foundation for the application of BFO nanowires in nanodevices.

The fabrication of melamine-treated graphene oxide (MGO) adsorbed on copper surface was reported. The composition and morphology of MGO were studied by FTIR, Raman, XPS, AFM and SEM analysis. These results clearly indicated that melamine was grafted on the surface of graphene oxide (GO). MGO could be spontaneously adsorbed on copper surface following the Langmuir adsorption isotherm and endow copper with hydrophobic surface. Meanwhile, the copper specimens adsorbed MGO exhibited high inhibition efficiency and outstanding anticorrosion performance according to the electrochemical measurements and immersion tests.