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• At elevated temperatures, TiO 2 (B) formed during laser powder bed fusion decomposes, leading to the formation of Ti 2 Ni precipitation. • The presence of Ti 2 Ni impedes the movement of grain boundaries, hinders grain growth, and serves as a brittle phase, resulting in brittleness in the NiTi alloy. Powder bed fusion-laser beam with metals (PBF-LB/M) can be used to manufacture intricate NiTi components. However, the ductility of NiTi alloys fabricated by PBF-LB/M is generally ∼20 % less than those made via conventional processes. Although many heat treatment methods have been proposed, solving this issue has been proven difficult. An intractable problem is the brittleness of PBF-LB/M-fabricated NiTi after solid-solution treatment at 1000 °C. By investigating the microstructural and fractography change after heat treatment in the range of 100–1000 °C, this study found that this ductile-to-brittle transition stems from abnormal oxygen-containing Ti-rich precipitates being generated in the PBF-LB/M fabricated Ni-rich NiTi. We identified laser processing-induced local oxygen segregation and tiny TiO 2 (B) particles at the fusion and grain boundaries. During the heat treatment at temperatures above 700 °C, these oxides decompose due to their low thermal stability. After this decomposition, most oxygen diffuses into the matrix, with titanium remaining in local regions. This process enriches titanium in the interfaces, forming a brittle oxygen-rich Ti 2 Ni network that is known to hinder the recrystallization process in heat treatment. Furthermore, when subjected to external loading, these precipitates can induce high misfit levels and local distortion, resulting in brittle fractures along the interfaces. Based on these results, we also propose approaches to avoid high-temperature-induced embrittlement in Ni-rich NiTi. [Display omitted] [ABSTRACT FROM AUTHOR]

Refractories have an important effect on the cleanliness of molten steel. The interaction between CeAlO3refractories and Ce treated steel was explored and compared with that between Al2O3refractories and Ce treated steel. The results show that the Ce content in steel decreases sharply after contact with Al2O3refractories and the pick-up of dissolved Al occurs. Compared with the test of Al2O3refractories, the loss of Ce content is less in the test of CeAlO3refractory, and the total oxygen content and dissolved Al content in steel increase less. The dense and continuous Ce2O2S interface layer is observed at the CeAlO3refractories/steel interface, which can serve as the metallurgical isolation layer and hinder the further interaction between refractories and steel. Therefore, the higher steel cleanliness and less penetration of refractories by molten steel are obtained in the test of CeAlO3refractories. The CeAlO3refractories show a promising prospect in the production of clean Ce treated steel.

In order to explore the corrosion mechanism of Al2O3–C refractories in the mold flux bearing MnO, the immersion test of Al2O3–C refractories in CaO–SiO2–CaF2–MnO slag with different MnO contents was carried out at 1550 °C. The results show that Mn particles were observed in the slag after experiment, due to the reduction of MnO by graphite in refractories. Large amounts of graphite were observed at the interface between refractories and slag, indicating that the oxidation of graphite is limited by the poor contact between graphite and molten slag. Therefore, the oxidation of graphite is not the main cause of damage to refractories. A small quantity of CaO·2Al2O3(CA2) and CaO·6Al2O3(CA6) adjacent to Al2O3grain was detected at the slag/reaction layer interface. CA2and CA6possess relatively high melting points, which is beneficial to hindering the further penetration of slag. However, the dissolution of Al2O3into slag is still the main cause for refractories damage. The increase in the MnO content of mold slag decreases the viscosity and then results in the severe corrosion of Al2O3–C bricks.

In this article, the experimental and finite element analysis is utilized to investigate the quasi-static compression features of sandwich constructions built with tapered tubes. 3D printing technology was utilized to create the hollow centers of the tapering tubes, with and without corrugations. The results demonstrate that the energy absorption (EA) and specific energy absorption (SEA) of the single corrugated tapered tube sandwich are 51.6% and 19.8% higher, respectively, than those of the conical tube sandwich. Furthermore, the results demonstrate that energy absorbers can benefit from corrugation in order to increase their efficiency. Additionally, the tapered corrugated tubes’ resistance to oblique impacts was studied. Compared to a straight tube, the tapered tube is more resistant to oblique loads and has a lower initial peak crushing force (PCF), according to numerical simulations. After conducting a parametric study, it was discovered that the energy absorption performance of the sandwich construction is significantly affected by the amplitude, number of corrugations, and wall thickness. EA and SEA of DTS with corrugation number of 8 increased by 17.4% and 29.6%, respectively, while PCF decreased by 9.2% compared to DTS with corrugation number of 10.

The introduction of analytic philosophy to China coincided with the second Eastern expansion of Western philosophy in China at the beginning of the twentieth century. The history of the study of analytic philosophy in China can be divided into four periods: the first half of the twentieth century, the time between 1949 and 1980, the 1980s until the end of the last century, and the beginning of the new century. There are four main research fields in which Chinese scholars of analytic philosophy have become interested in succession: the philosophy of science, the philosophy of language and logic, the philosophy of mind, and the philosophy of cognitive science. Modern Chinese philosophy has been integrated with ancient Chinese, Western, and Marxist philosophy. This integration is grounded in some holistic features of contemporary Chinese philosophy, in which textual research, philosophical interpretation, and empirical reasoning as analytic methods are illuminated. [ABSTRACT FROM AUTHOR]

ABSTRACTThe absolute maximum response (AMR) of structures might occur posterior to the end of earthquake excitations, hence, extending the dynamic analysis to the post-shaking phase is required. This phenomenon was found to be more common for long-period and low-damping structures, which are prevailing in regions of low-to-moderate seismicity like Australia. In this article, the mechanism of the occurrence of AMR in the post-shaking phase is first explained using single-degree-of-freedom (SDOF) systems subjected to a simple sine wave. Further investigation on real earthquake ground motions reveals that whether an extended analysis is required depends greatly on the characteristics of the post-significant duration phase. Finally, suitable metrics for describing ground motions that require extended analysis (EAGMs) are identified based on the Kolmogorov–Smirnov test. Regression analyses are then conducted to predict the probability of EAGMs.

A series of nano-WC surface modified AlSi10Mg powders with different WC contentswere synthesized by the electrostatic assembly method. After the selective laser melting (SLM) processing, various Al−W intermetallicswere in-situ formed in the SLM nano-WC/AlSi10Mg composites. A well-coherent Al/Al5W interface with a low lattice mismatch of 4.7% was confirmed with an orientation relationship of (002)α(Al)//(104)Al5W. The nano-WC particles and Al−W intermetallics triggeredthe columnar-to-equiaxed transition, leading to a fine equiaxed microstructure. As a result, the SLMed 3 wt.% nano-WC/AlSi10Mg composites showed remarkable mechanical properties, with an ultimate tensile strength of (464.1±8.68) MPa and elongation of (5.6±0.95)%. Additionally, the SLMed 3 wt.% WC/AlSi10Mg samples also achieved the lowest average coefficient of friction (0.429) and wear rate of 3.842×10−5mm3/(N·m) compared to other WC/AlSi10Mg composites. The remarkable mechanical and wear properties are ascribed to fine-grain and second-phase strengthening.

Although the incidence and death rates of gastric cancer (GC) are decreasing, approximately one million new cases and 800,000 GC‐related deaths were reported worldwide in 2018. Currently, the oncogenesis of GC remains unclear, and the demand for novel treatment options are unmet. Here, we explored the role of aldo‐keto reductase family 1 member B (AKR1B1) in the progression of GC. The proliferation, migration, and invasion of GC cells were evaluated by CCK‐8 assay, wound healing assay, and transwell assay, respectively. The interaction between EBF transcription factor 1 (EBF1) and the promoter region of AKR1B1 was determined by luciferase reporter assay and chromatin immunoprecipitation (ChIP). Gene expression levels were measured by quantitative real‐time polymerase chain reaction (qRT‐PCR) and Western blotting assay. The expression of AKR1B1 was elevated in GC cells, resulting in increased cell proliferation, migration, and invasion. Meanwhile, EBF1 was a negative regulator of AKR1B1; its overexpression suppressed AKR1B1 expression and GC progression. Furthermore, knockdown of ZNF521 induced EBF1 expression, thus suppressing AKR1B1 expression and resulting in attenuated GC growth and invasiveness. Notably, knockdown of ZNF521 attenuated GC progression and was rescued by overexpression of AKR1B1. Our current study revealed a novel ZNF521/EBF1/AKR1B1 axis in GC and elaborated its important role in promoting GC progression, providing potential therapeutic targets for anti‐GC treatments.

Oral squamous cell carcinoma (OSCC) is one of the most frequent malignancies found in head and neck cancers. Dysregulation of lncRNAs has been proposed to be related to the development of OSCC. Here, we investigated the function and probable mechanisms of lncRNA DLEU1 in OSCC. OSCC cell lines and human oral keratinocytes (HOKs) were cultured, while SCC‐25 and CAL‐27 cells were transfected with the corresponding plasmids. Reverse transcription quantitative PCR (RT‐qPCR) and western blot were carried out to measure the RNA and protein levels. Cell proliferation, migration and invasion were evaluated using MTT assays, wound healing and Transwell assays. The StarBase database predicted the interactions between DLEU1 and miR‐126‐5p, as well as miR‐126‐5p and GAB1, which were further validated using a dual‐luciferase reporter assay. Our results indicated that DLEU1 and GAB1 were upregulated, while miR‐126‐5p was downregulated in OSCC cells. Silencing DLEU1 reduced OSCC cell proliferation, migration, and invasion, while DLEU1 overexpression had the opposite effects. DLEU1 mediated biological effects in OSCC through binding to miR‐126‐5p, which directly targeted GAB1. miR‐126‐5p knockdown rescued the inhibitory function of DLEU1 depletion on proliferation, migration and invasion. Meanwhile, the miR‐126‐5p mimic exerted suppressive functions in the progression of OSCC, which were neutralized after GAB1 overexpression. In summary, lncRNA DLEU1 targets the miR‐126‐5p/GAB1 axis to aggravate OSCC progression, providing a novel target for treating OSCC.

Over the past decade, the electric vehicle industry of China has developed rapidly, reaching one of the highest technological levels in the world. Nevertheless, most electric buses currently serve urban areas, being unsuitable for all-climate operations. In response to the objective of massively adopting electric vehicles for transportation during all the events of the 2022 Beijing Winter Olympics, a dual-motor coaxial propulsion system for all-climate electric vehicles is proposed. The system aims to meet operating requirements such as high speed and adaptability to mountainous roads under severely cold environments. The system provides three operating modes, whose characteristics are analyzed under different conditions. In addition, dual-motor collaborative control strategy with collaborative gearshift and collaborative power distribution is proposed to eliminate power interruption during gearshift process and achieve intelligent power distribution, thus improving the gearshift quality and reducing energy consumption. Finally, gear position calibration for all-climate operation and proper gearshift is introduced. Experimental results demonstrate the advantages of the proposed dual-motor coaxial propulsion system regarding gearshift compared with the conventional single-motor automatic transmission.

Stay cables in cable-stayed bridges are essential components to transmit deck loadings. However, cable loss events have been occasionally observed both in service life and under extreme situations like earthquakes. This study systematically investigates the seismic performance of a case cable-stayed bridge considering the loss of one cable or multiple cables during earthquake excitations. It is revealed that the cable loss would lead to the larger seismic demands of the cable-stayed bridge whereas the detrimental effect due to cable loss is highly sensitive to the cable loss location and loss stress. In general, the loss of the longer cable would be more harmful to the bridge system due to the back-stay effect. Meanwhile, the largest seismic response is reached when the maximum cable-loss-induced responses and the maximum earthquake-induced responses occur at the same time. The loss of one cable causes a large increase in force variation of the adjacent cables, which might lead to progressive cable loss. The ultimate states of the bridge are defined concerning the ultimate longitudinal displacement at the deck end, the ultimate deck bending moment, and the ultimate tower bending moment. The case cable-stayed bridge can sustain at maximum the loss of four cables; otherwise the ultimate state of the longitudinal displacement at deck end is exceeded. Due to the significant interactions between the oscillations induced by the earthquake and by the cable loss, the linear superposition method does not apply to the seismic response of the bridge including the cable loss effect.

A meso-analysis method which is derived from the base force element method (BFEM) was proposed for recycled aggregate concrete (RAC). A simple algorithm was used to generate the convex recycled concrete aggregate (RCA) model. Uniaxial compression numerical simulations were carried out on the numerical specimens with different replacement rates of RCA. The model predictions were in a good agreement with the test results. The proposed method is very promising. It can totally predict the full stress-strain curve of RAC, as well as the failure process and failure mode, including strain softening and strain localization.

In the design of a BeiDou navigation satellite system(BDS) receiver, the carrier loop is largely influenced by the loop filter, and the selection of loop filter parameters is crucial to the performance of the carrier loop. In this paper, by analyzing the relationship between the parameters of the loop filter transfer function of the BDS receiver's fourth‐order carrier loop system and the time‐domain index of the system, the loop filter transfer function parameters of the fourth‐order system are obtained when the dynamic performance is best optimized under the condition that the maximum steady‐state error is limited. The relationship between the phase margin, magnitude margin of the system and the parameters of the system transfer function is obtained through simulation experiment and theoretical derivation. The simultaneous equations of deriving the loop system transfer function parameters are given under the following conditions: the optimal phase margin and magnitude margin of the system are settled. These research results have important reference significance for the design of a high‐performance BDS receiver.

Impact flash occurs when objects collide at supersonic speeds and can be used for real-time damage assessment when weapons rely on kinetic energy to destroy targets. However, the mechanism of impact flash remains unclear. A series of impact flash experiments of flat-head long-rod projectiles impacting thin target plates were performed with a two-stage light gas gun. The impact flash spectra for 6061 aluminum at 1.3–3.2 km/s collision speeds were recorded with a high-speed camera, a photoelectric sensor, and a time-resolved spectrometer. The intensity of the impact flash exhibited a pulse characteristic with time. The intensity (I) increased with impact velocity (V0) according to I∝V0n, where n = 4.41 for V0 > 2 km/s. However, for V0 < 2 km/s, n = 2.21, and the intense flash duration is an order of magnitude less than that of higher V0. When V0 > 2 km/s, a continuous spectrum (thermal radiation background) was observed and increased in intensity with V0. However, for V0 < 2 km/s, only atomic line spectra were detected. There was no aluminum spectral lines for V0 < 2 km/s, which indicated that it had not been vaporized. The initial intense flash was emission from excited and ionized ambient gases near the impact surface, and had little relationship with shock temperature rise, indicating a new mechanism of impact flash.

Barium strontium zirconate titanate ceramics ((BaSr)(ZrTi)O3-BSZT) with Zr4+ionic contents of 15 and 20 mol % and Sr2+ionic contents of 15, 20, 25, and 30 mol % were prepared using a solid-state reaction approach. X-ray diffraction and scanning electron microscopy were used to characterize the lattice structure and morphologies of the ceramics. Permittivity and polarization as a function of temperature were characterized using an impedance analyzer and a Tower–Sawyer circuit. The electrocaloric effect was measured directly and calculated using the Maxwell relation (indirectly). The results indicated that the BSZT ceramics change from a normal ferroelectric to a relaxor ferroelectric with increasing Zr4+ionic content, which can be further modified by the addition of Sr2+ionic content. The optimized adiabatic temperature change ΔTobtained is 2.43 K in (Ba0.85Sr0.15)(Zr0.15Ti0.75)O3ceramics, and ΔT>1.6 K over a wide temperature span of 120 °C was obtained.

Microstructure design of high-strength materials based on single-principal-microstructure advantage can hardly meet the increasingly strict service requirements of modern aviation and aerospace industries. Compared with conventional forming methods, additive manufacturing (AM) technology introduces more regulatory variables, making it possible to gain multiple microstructure advantages simultaneously for critical components. This study introduces a universal process strategy in laser-powder bed fusion (L-PBF) to achieve hierarchical-microstructure optimization for titanium alloys. Specifically, a higher energy density can refine (R) martensite lath, and an appropriate scanning strategy can split (S) both coarse prior-β grains and α’-colony. For L-PBF-fabricated Ti-6Al-4 V (Ti64) alloy, the proposed refinement-splitting (R & S) optimization strategy improved yield strength (up to ∼1.3 gigapascals) by 30% and the total elongation increase by about 1.9 times compared to the alloy samples with a conventional rich α’-colony microstructure. The split prior-β grains also help with the complex service environment by reducing the anisotropy-induced deterioration of mechanical properties. The R&S approach is, in principle, applicable also to other titanium alloys beyond Ti64.

N-Acetylgalactosamine (GalNAc)-conjugated small interfering RNA (siRNA) therapies have received approval for treating both orphan and prevalent diseases. To improve in vivoefficacy and streamline the chemical synthesis process for efficient and cost-effective manufacturing, we conducted this study to identify better designs of GalNAc-siRNA conjugates for therapeutic development. Here, we present data on redesigned GalNAc-based ligands conjugated with siRNAs against angiopoietin-like 3 (ANGPTL3) and lipoprotein (a) (Lp(a)) two-target molecules with the potential to address large unmet medical needs in atherosclerotic cardiovascular diseases. By attaching a novel pyran-derived scaffold to serial monovalent GalNAc units before solid-phase oligonucleotide synthesis, we achieved increased GalNAc-siRNA production efficiency with fewer synthesis steps compared to the standard triantennary GalNAc construct L96. The improved GalNAc-siRNA conjugates demonstrated equivalent or superior in vivoefficacy compared to triantennary GalNAc-conjugated siRNAs.

The effects of resveratrol (RES)-loaded whey protein isolate (WPI)–dextran nanocomplex on the physicochemical stability of β-carotene (BC) emulsions were evaluated. WPI–dextran was prepared by Maillard-based glycation and confirmed with gel electrophoresis and OPA assay. WPI–RES and WPI–dextran–RES nanoparticles were prepared with a simple nanocomplexation protocol. Fluorescence spectra indicated that hydrophobic interaction was the main driving force for the WPI–dextran–RES nanocomplex. Spherical and uniformly dispersed structures as well as nanoscale Z-average size (<100 nm) were confirmed for WPI–RES and WPI–dextran–RES nanocomplex with DLS and TEM. The Z-average diameter of emulsions with WPI–dextran conjugate was remarkably lower than that with WPI. Environmental stress (ionic strength, heat, and pH) and storage stability were pronouncedly improved. The chemical stability of BC with WPI–dextran–RES and WPI–RES was also remarkably enhanced when exposed to UV light and thermal treatment. The advantages of the WPI–dextran–RES colloidal complex may provide a better alternative to effectively protect and deliver hydrophobic nutraceuticals.

Calmodulin (CaM) is a pivotal multifunction regulator of calcium metabolism in nearly all organisms, and earlier studies revealed its underlying involvement of shell or pearl formation in oysters. Culture pearls are formed within complete pearl sacs. However, whether CaM functions in pearl sac formation or not is not reported. In this study, we prepared a polyclonal antibody against the CaM from the freshwater pearl mussel Hyriopsis schlegelii(HsCaM) and then detected the expression and distribution of HsCaM in pearl sac using the method of immunofluorescence in situ hybridization (IISH). Results revealed that strong fluorescent signals were observed in pearl sac as well as epithelial border of mantle. In addition, quantitative analysis results indicated that the mRNA expression level of HsCaMin pearl sac of H. schlegeliiwas significantly up-regulated during pearl sac formation. The fact that HsCaM highly expressed is present in pearl sac suggested that it might facilitate pearl sac formation in H. schlegelii.

Barium zirconate titanate (BZT) (Ba(ZrxTi1–x)O3) ceramics with Zr4+contents of x= 5, 10, 15, 20, 25, and 30 mol % were prepared using a solid-state reaction approach. The microstructures, morphologies, and electric properties were characterized using X-ray diffraction, scanning electron microscopy, and impedance analysis methods, respectively. The dielectric analyses indicate that the BZT bulk ceramics show characteristics of phase transition from a normal ferroelectric to a relaxor ferroelectric with the increasing Zr4+ionic content. The electrocaloric effect adiabatic temperature change decreases with the increasing Zr4+content. The highest adiabatic temperature change obtained is 2.4 K for BZT ceramics with a 5 mol % of Zr4+ionic content.

Although tremendous efforts have been devoted to the exploration of cost-effective, active, and stable electrochemical catalysts, only few significant breakthroughs have been achieved up to now. Therefore, exploring new catalysts and improving catalyst activity and stability are still major tasks at present. Controllable synthesis of Pt-based alloy nanocrystals with a uniform high-index surface and unique architecture has been regarded as an effective strategy to optimize their catalytic efficiency toward electrochemical reactions. Accordingly, here we present a one-pot facile solvothermal process to synthesize novel unique Cu@CuPt core–shell concave octahedron nanocrystals that exhibit both outstanding activity and long durability. By regulating temperatures during the synthesis process, we were able to control the reduction rate of Cu and Pt ions, which could subsequently lead to the sequential stacking of Cu and Pt atoms. Owing to the concave structure, the as-prepared core–shell nanoparticles hold a high-index surface of {312} and {413}. Such surfaces can provide a high density of atomic steps and terraces, which is suggested to be favorable for electrochemical catalysts. Specifically, the Cu@CuPt core–shell concave octahedron presents 8.6/13.1 times enhanced specific/mass activities toward the methanol oxidation reaction in comparison to those of a commercial Pt/C catalyst, respectively. Meanwhile, the as-prepared catalyst exhibits superior durability and antiaggregation properties under harsh electrochemical conditions. The facile method used here proposes a novel idea to the fabrication of nanocrystals with desired compositional distribution, and the as-prepared product offers exciting opportunities to be applied in direct methanol fuel cells.

Abstract

We report what we believe to be potential improved performance for a Nd:YAG discrete path slab amplifier configuration based on a hybrid resonator system. The amplifier is driven by a Q-switched 0.3 mJ nanosecond oscillator that generates an initial laser pulse at a repetition rate of 5 KHz and has beam quality of M^2<1.3. The input pulse makes 12 passes through the slab amplifier to yield 25 mJ output pulse energy at the absorbed pump power of 878 W. A corresponding optical-to-optical efficiency of 14.3% was obtained, and the beam quality factors M^2 in the unstable and stable direction were 1.7 and 1.5, respectively. No detectable signs of amplified spontaneous emission were observed.

A series of slag were fabricated by self-shield welding of different flux-cored wire. The microstructure and phase composition of those slag were investigated by means of metallographic microscope, SEM,EDX and X-ray diffraction respectively. The result demonstrated that the slag forming material of TiO2 and Al2O3 tenders to form the framework structure of slag, while CaO and MnO2 inclines to incorporate in the grain boundary. Furthermore, the dense and dendrite phase structure of slag was beneficial for the removal of slag. On the contrary the slag with tiny needle and skeleton-like structure was difficult to clear up. In conclusion, the detachability performance was not only affected by the microstructure, but also by the chemical composition of the slag system.

A convenient and efficient approach was developed to synthesize α-Kdo O-glycosides based on the Tf2O/(p-Tol)2SO preactivation strategy using peracetylated Kdo thioglycoside as a donor. Under the optimized reaction conditions, several O-glycoside products, including α-(2 → 1)-, α-(2 → 2)-, α-(2 → 3)-, and α-(2 → 6)-Kdo products, were stereoselectively synthesized in high yields. Remarkably, a series of aromatic α-Kdo O-glycosides were first and successfully constructed in high yields. An SN2-like mechanism was revealed by DFT calculations and experimental results.

The article focuses on the quality management of the fiber-reinforced plastic (FRP) crude oil pipelines. Topics discussed include the importance of crude oil pipelines safety management, the thermal insulation of FRP, and the thermal conductivity management. Also mentioned are the effects of soil temperature to oil pipelines and the heat transfer simulation.

In die-sinking EDM processing of deep complex cavities, gap status is easy to be deteriorated because of the hardness of debris evacuation. To address this problem, a kind of porous material was applied as the tool electrode. The porous material was prepared by the way of high-temperature sintering of copper particles. With a proper sintering parameters setting, a porous electrode, in which copper particles connect with each other tightly, is able to be fabricated according to a graphite mould. The porous electrode also has a high porosity such that liquid flow channels are formed and the distributed multi-hole inner-flushing can be achieved. A complex porous electrode for the machining of a deep, complex, and semi-enclosed cavity was prepared, and the EDM experiment was carried out. The experimental results showed that the roughing machining efficiency was raised significantly, which therefore revealed a strong capability of porous electrode in complex cavity machining.

Metal oxide nanotubes have been synthesized with varied methods based on mechanisms such as the Kirkendall effect, dislocation-driven growth, and so on. However, most of these methods pose a challenge to these thermally unstable metal oxides. Herein, we first adopted the concept of electrochemical corrosion in the successful synthesis of scalable tubular Cu2O nanoparticle (>10 μm in length, 20–500 nm in diameter) in aqueous solution at room temperature. By investigating different growth stages of the reaction process, a CuBr2–ion diffusion mechanism was rationally put forward associating with the literature, instead of the atom diffusion mechanism in the Kirkendall effect. The products exhibit outstanding specific surface area and photocatalytical activity. The present method provides a new route for synthesizing metal oxides with hollow structures.

The two-dimensional material MoS2 has attracted a growing attention due to its potential applications in electronic devices in recent years [1,2,3], and the monolayer MoS2 is a direct gap semiconductor with a band gap of 1.8eV [4]. In the existing studies, it has indicated that MoS2 can get an available magnetism with doping transition metal atoms [5], and is expected to be a new generation of diluted magnetic semiconductor (DMS) [6,7]. Moreover, we found that Fe-doped MoS2 could present a strong magnetism but a semimetal characteristic, losing its original semiconductor properties while obtaining magnetism. Therefore, it is necessary to explore some methods to make monolayer MoS2 exhibit both magnetic and semiconductor properties. In this paper, we propose the method of N, Fe atoms co-doping to achieve this objective. The structural, electronic and magnetic properties of MoS2 doped with transition metal Fe and VA atoms have been investigated by first principle calculations based on density functional theory. The 3×3×1 supercell of monolayer MoS2 as a calculation model has been used. The result shows that pure MoS2 has no magnetism, while Fe-doped MoS2 exhibits a good magnetism about 1.849μB but a semimetal characteristic. This is due to that Mo-4d, S-2p, Fe-3d states has a strong coupling around the Femi energy for the introduction of Fe atom, and the Femi energy only pass through the spin-up density of states. For the co-doping with VA atoms and Fe atoms, it is found that the magnetic moment of Fe-N, Fe-P and Fe-As co-doped MoS2 is 0.956μB, 0.775μB, 0.782μB. Moreover, the Fe-N co-doped MoS2 presents semiconductor characteristics, in contrast, Fe-P and Fe-As co-doped MoS2 appear semimetal properties. It indicates that the semimetal characteristic of Fe-doped MoS2 could change into indirect band gap semiconductor due to the introduction of N atom. The band gap is 0.2eV. Our study demonstrate that the method of Fe, N co-doping could make MoS2 have good magnetic and also semiconductor properties at the same time.

It has been a century since Wittgenstein was introduced into China, and his philosophy has been in conflict with traditional Chinese philosophy and culture ever since. During this time, Wittgenstein’s philosophy has been the focus of considerable dialogue regarding Chinese and Western philosophies and has been responsible for introducing many new ideas into Chinese philosophy. There are three ways to study Wittgenstein’s philosophy in China: contextual reading, interpretation of thoughts and extended understanding. Chen Jiaying is one of the foremost scholars of the study of Wittgenstein in China. This scholar incorporates Wittgenstein’s methodology, especially in his later philosophy, to explain meanings of ordinary language. Wittgenstein’s philosophy introduces anti-essentialism into Chinese studies, a new way to interpret the philosophy of language, and his criticism of traditional Western philosophy. Taken together, these factors emphasise the significance of Wittgenstein’s philosophy to philosophical research in China.

Using the prepared gas-shielded flux-cored wire for welding 600MPa high strength steel, the 921A high strength steels were welded at different weld heat input condition of 10 kJ/cm, 15 kJ/cm and 20 kJ/cm. The influence of weld heat input on the electrochemical behavior of the 921A high strength steel welding joints were studied in this paper. The results show that, at different weld heat input condition, the linear polarization resistances (LPR) of all the welding joints welded by using the prepared flux-cored wire were close to that of the 921A base steel, as can be identified as the same LPR value at 15 kJ/cm weld heat input condition. By observing the surfaces of the linear polarized welding joints samples, it was found that the welding joint at 15 kJ/cm weld heat input had the smallest corrosive area by macro observing, showing the pitting corrosion by micro observing and presents the least corrosion pit.

The simulation of support settlement of a transmission angle-tower is actively carried out in this study based on the actual structural damage events. The mechanical model of the transmission angle-tower is developed based on the spatial member finite element approach. The finite element model of the transmission tower-line system is constructed by taking a real 220KV transmission tower as an example. The support settlement of the tower is analyzed and the collected information are utilized in the structural finite element analysis. The made observations indicate that the support settlement may induce large structural internal forces, which may induce potential disk to the structural safety.

Five new icetexane diterpenoids, namely, perovskatones B-D (1, 3, 4), 1α-hydroxybrussonol (2), and 1α-hydroxypisiferanol (5), were isolated from Perovskia atriplicifolia, together with a new natural product (6) and two known compounds, przewalskin E (7) and brussonol (8). The structures of the new compounds were elucidated by detailed analyses of their MS, IR, 1D, and 2D NMR data. Compounds 1-8 were assayed for their inhibitory hepatitis B virus activities in the HepG 2.2.15 cell line. The results suggested that compounds 1 and 2 possessed noticeable anti-hepatitis B virus activity in vitro, suppressing the replication of hepatitis B virus DNA with selectivity index values of 154.3 and 137.7, respectively. [ABSTRACT FROM AUTHOR]

The field investigation and assessment on base conditions of a transmission tower in coastal mound areas is actively carried out in this study. A transmission tower constructed in the southern areas of China is taken as example to examine the geological characteristics. The detailed geological investigation and field inspection were performance for the safety assessment of the tower-foundation system. The geological investigation was carried out based on the Chinese specifications and codes by taking into consideration many factors, such as the base terrain, topographical features, traffic conditions and etc. Testing types and sample numbers of the geological investigation includes the geological exploration, drilling, geotechnical sampling, in situ testing and setting-out measurement.

The dynamic response analysis of a transmission angle tower subjected to wind excitations is actively carried out in this study. The structural model is constructed based on finite element approach with the aiding of commercial package ANSYS. The equation of motion of the transmission tower-line system under wind excitations is established. The dynamic wind loading are applied on the tower-line system to examine the structural responses. The deformation and stresses distribution of the transmission angle tower are computed to explore the structural performance. The made observations indicate that the peak stresses of some members are large than the permitted yielding stresses of steel material.

Use Geomagic Qualify software, take the distance between the measure point and the surface model as the main evaluation index, respectively evaluate the quality of the shoe last surface reconstructed by tradition surface modeling way and quickly surface modeling approach, through 3D comparison, 2D comparison and special point comparison, get the 3D deviation chart and the error percentage distribution list, through the analysis and comparison of the charts, the two ways of surface reconstruction method are in line with the requirements of the surface, select the appropriate method of surface reconstruction according to the different requirements of surface reconstruction quality, provide the reference basis to surface measurement and surface reconstruction of other models.

The dislocation cellular pattern (DCP) is a predominant microstructure in laser-based additively manufactured metals. Understanding the evolution of DCP paves the way for optimizing the laser-produced microstructure, which can ultimately modify the mechanical properties. In this work, we combined tensile test and multiscale characterization methods to systematically study the development of DCP in deformed Inconel 718 alloy that was processed with laser powder-bed fusion technique. Although the DCP has a similar appearance as the deformation-induced dislocation cell, the wall of DCP consists of solute atoms and small precipitates, which are absent in the conventional dislocation cell. The development of DCP during plastic deformation was independent of crystal orientation. The evolution process of DCP can be divided into two stages. At a tensile strain lower than 10%, the size of DCP was independent of flow stress. At higher strain levels, the DCP size decreased; however, the maximum reduction obtained at the strain-to-failure was only ~27% of the undeformed DCP size. The geometrically necessary dislocation density at DCP boundaries increased as increasing strain. Because of the interactions of dislocation tangles, solute atoms, and precipitates in the DCP wall, the DCP configuration is stabilized, and its role in deformation was neither like that of the dislocation cell nor that of the grain boundary.

A simulation system for intertidal zone environment that can be remotely monitored is proposed. The system is divided into the two parts of remote control center and environment simulator, which are interconnected through wireless network technology. The remote control center performs remote monitoring through upper machine software, while the environment simulator can simulate natural environments such as ocean tides, water temperature and light illumination in different types of intertidal zones. Users can change and access the environmental parameters and data of the environment simulator by making instructions at the remote control center. A stable system is realized in accordance with the design requirements, and actual tests show that main features of the simulated natural environment in intertidal zones are very close to actual environment.

n this paper, Using CSMC 0.5μm CMOS process to design each sub-module, the circuit simulation, and adjustment and validation of parameters have been carried out by simulation tools. The low static power and high conversion efficiency charge pump LED driver circuit has been designed. The circuits nucleus module is adaptive charge pump (1x/1.5x/2x charge pump), to converse a wider range of input voltage to a constant output voltage with high efficiency. This circuit only needs some external capacitors, and dont need inductor. So it reduces EMI electromagnetic interference and application cost, etc.

In this paper, high-speed vertical machining center of the four schemes(namely general reinforcement worktable, strength general reinforcement worktable, diagonal reinforcement worktable and strength diagonal reinforcement worktable) has been entity modeling in Soldworks. After modeling, do finite element analysis and stiffness analysis to four schemes, the conclusion shows strength reinforcement worktable is the best plan. Then, do modal analysis in order to improve the inherent frequency, get the modal of the system frequency and vibration mode. Finally, according to the results of analysis of static dynamics, in order to improve the natural frequencies of strength general reinforcement system, the worktable has been topological optimization. Because of the result of the topological optimization is not obvious, so choose workbench is verified by reasonable structure.

The key techniques of reverse engineering include data acquisition, data processing and model reconstruction.In this paper, with the automobile rearview mirror shell for example, scan the rearview mirror shell surface by laser scanner; then carries on the data processing to point cloud data(data processing include point cloud data registration, joining together and polygon stage processing). On the basis of data processing, fitting NURBS surface by Geomagic Studio software, thus completing surface reconstruction; Finally through the NC machining simulation, gets CNC programming, and to make the rearview mirror surface reconstruction and the numerical simulation.

In traditional single-screw worktable system, the system is always subjected with torque because the driving force and force-bearing point of the workpiece always change with the processing path, so its performance may be affected. Therefore, the scheme of dual-screw worktable system is put forward and modal analysis with ANSYS Workbench is made by taking DVG850 high-speed vertical machining center worktable system for example. Then four alternatives of the machine are proposed based on the position of screw and guide.Through modal analysis of different parameters of the system, we ultimately select the dual-screw worktable system with highest performance (Screws place inside of the guide and horizontal distance of the two screws is 310mm.) as the optimalizing plan. This provides a reliable reference for further study on dynamic analysis of worktable system.