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Hydrogen bonding is a vital driving force for organizing the hierarchy molecular structure, especially in biologic field. Due to its directionality, selectivity and moderate strength, hydrogen bonding has been extensively introduced into the molecular recognition, sensing and electronic devices. Electric meas-urements at single-molecule level facilitate the investigation of hydrogen bonds and provide a comprehensive understanding of the electron transport properties governed by the hydrogen bonding, which is essential for the development of self-assembled electronic systems. This review provides a de-tailed overview of recent advancements in constructing single-molecule junctions utilizing intramolecular and intermolecular hydrogen bonding. We first introduce the methods utilized for characterizing the electric and dynamic properties of non-covalent interactions. Next, we discuss the mechanisms of electron transport, relevant influencing factors, and typical applications utilizing electrical signals based on single-molecule junctions. Finally, we propose our perspective on the existing challenges and prospective opportunities in utilizing hydrogen bonding for electronic device applications.

Quantum interference (QI) has been identified as a promising strategy for designing molecular-scale electronic devices. Heteroatom doping can effectively tailor the local structures and electronic states of intrinsic molecules, and endow them with modified electron transport properties. Herein, the impacts of multiple heteroatom substitution on destructive quantum interference (DQI) have been investigated based on tripodal

Thermally-induced phase transformation (PT) is of significance and value to the application of NiTi alloy components. Low-temperature aging (LTA) treatment was used to alter PT characteristics of NiTi alloys avoiding undesirable grain growth. Effect of LTA on PT of NiTi wires with a wide range of grain sizes from 34 nm to 8021 nm was investigated in this study. As the average grain size varies from 34 to 217 nm, the temperature of the B2↔R transformation increase as a result of LTA, and the increasing effect is more obvious at a larger grain size. For NiTi alloys with average grain sizes ranging from 523 to 1106 nm, transformation sequence changes from B2↔B19' to B2↔R due to LTA. For the sample with an average grain size of 2190 nm, the B2↔B19' transformation is replaced by B2↔R←B19' after LTA. When the average grain size is larger than 2190 nm, transformation sequence changes from B2↔B19' to B2↔R↔B19' after LTA. Transmission emission microscope observations reveal that the above-mentioned PT behavior correlates with the coupled effect of grain size and precipitation. The precipitation of Ni4Ti3 in the grains with a size smaller than ~150 nm is inhibited after LTA, the temperature of B2→R of samples with average GS smaller than ~150 nm still is elevated due to the inhomogeneous grain size of NiTi wires.

Image-based target tracking methods rely on continuous image acquisition and post-processing, which will result in low tracking efficiency. To realize real-time tracking of fast moving objects, we propose an image-free target tracking scheme based on the discrete cosine transform and single-pixel detection. Our method avoids calculating all the phase values, so the number of samples can be greatly reduced. Furthermore, complementary modulation is applied to reduce the measurement noise, and background subtraction is applied to enhance the contrast. The results of simulations and experiments demonstrate that the proposed scheme can accomplish the tracking task in a complex background with a sampling ratio of less than 0.59% of the Nyquist-Shannon criterion, thereby significantly reducing the measurement time. The tracking speed can reach 208 fps at a spatial resolution of 128 × 128 pixels with a tracking error of no more than one pixel. This technique provides a new idea for real-time tracking of fast-moving targets.

The application of solid-state batteries (SSBs) is challenged by the inherently poor interfacial contact between the solid-state electrolyte (SSE) and the electrodes, typically a metallic lithium anode. Building artificial intermediate nanofilms is effective in tackling this roadblock, but their implementation largely relies on vapor-based techniques such as atomic layer deposition, which are expensive, energy-intensive, and time-consuming due to the monolayer deposited per cycle. Herein, an easy and low-cost wet-chemistry fabrication process is used to engineer the anode/solid electrolyte interface in SSBs with nanoscale precision. This coordination-assisted deposition is initiated with polyacrylate acid as a functional polymer to control the surface reaction, which modulates the distribution and decomposition of metal precursors to reliably form a uniform crack-free and flexible nanofilm of a large variety of metal oxides. For demonstration, artificial Al

Scope Peanut stem and leaf (PSL), a traditional Chinese medicine, is widely used as a dietary supplement to improve sleep quality, however, the underlying mechanism is unclear. Here, we aimed to determine whether active compounds in PSL extract exert their effects by mediating neuronal excitability. Methods and results Aqueous PSL extract (500 mg/kg BW) increased the duration of total sleep (TS), slow wave sleep (SWS) and rapid eye movement sleep (REMS) in BALB/c mice after 7 and 14 continuous days of intragastric administration. Two PSL extract components with flavonoid-like structures: 4',7-di-O-methylnaringenin (DMN, 61 μg/kg BW) and 2'-O-methylisoliquiritigenin (MIL, 12 μg/kg BW), showed similar effects on sleep in BALB/c mice. Moreover, incubation with DMN (50 μM) and MIL (50 μM) acutely reduced voltage-gated sodium and potassium currents and suppressed the firing of evoked action potential in mouse cortical neurons, indicating the inhibition on neuronal excitability. Meanwhile, RNA-seq analysis predicted the potential regulation of voltage-gated channels, which is according with the molecular docking simulation that both MIL and DMN can bind to Nav 1.2. Conclusions DMN and MIL are the active ingredients of PSL that improve sleep quality, suggesting that PSL promotes sleep by regulating the excitability of neurons. This article is protected by copyright. All rights reserved.

The fertilizer and shading management of Coffea arabica in dry-hot area is extensive, resulting in lower yield and fertilizer utilization efficiency. A field experiment was carried out to find the coupling mode of shading and fertilizer for fertilizer-saving and high yield of C. arabica in dry-hot region. Four shading levels (100% NR, 75% NR, 60% NR, 45% NR, NR was natural radiation) and four fertilizer levels (No fertilization and 666.67, 1000, 1333.33 kg·hm干热区小粒咖啡肥光管理粗放,产量和肥料利用率受到限制。为探明干热区小粒咖啡节肥高产的肥光耦合模式,通过大田试验,设置4个遮荫度(100%NR、75%NR、60%NR、45%NR,NR为自然光照)和4个施肥量(不施肥及666.67、1000、1333.33 kg·hm

Laccases (EC 1.10.3.2) are a class of metallo-oxidases found in a variety of fungi, plants, and bacteria as well as in certain insects. They can oxidize a wide variety of organic compounds and can be widely applied in many fields, especially in the field of biodegradation and detoxification of environmental pollutants. The practical efficacy of laccases depends on their ability to capture the target substance as well as their catalytic activity, which is related to their catalytic center, substrate selectivity, and substrate tolerance. Over the past few decades, many laccases have been identified in plants and fungi. Concurrently, bacterial laccases have received increasing attention because of their high thermostability and high tolerance to organic compounds. The aim of this review is to summarize the role of bacterial laccases in the bioremediation of petroleum hydrocarbons and to outline the correlation between the molecular structure of the mononuclear T1 Cu center of bacterial laccases and their substrate preference.

In order to improve the thermal shock behavior of high temperature resistant coating on porous fibrous referactory insulations, the MoSi2-BaO-Al2O3-SiO2(MoSi2-BAS) gradient porous coatings were designed by preparing a dense surface layer and a porous bonding layer with the method of brushing and subsequent sintering at 1773 K. The porous bonding layer was obtained by adding polymethyl methacrylate (PMMA) as pore former. As the content of PMMA increases, the MoSi2-BAS coatings changed from a dense structure into a gradient porous structure. The interface bonding strength and thermal shock resistance of the MoSi2-BAS coatings were investigated. The result shows that the as-prepared coating with gradient porous structure exhibited excellent thermal shock resistance, which remained gradient structure without cracking after thermal cycling 100 times between 1773 K and room temperature. And the interface bonding strength of the gradient porous coating reached 1.5±0.08 Mpa, which was much better than that of the dense coating.

In this study, W-(Y0.9La0.1)2O3 composite powders are fabricated by means of a combination of wet chemical method and spark plasma sintering. We systematically study the sintering and densification behavior of W-(Y0.9La0.1)2O3 composite powders at different temperatures and pressures. The results indicate that ultrafine tungsten-based composites with a dispersed distribution of (Y0.9La0.1)2O3 particles can be achieved under optimized temperature and pressure conditions. The optimized pressure and sintering temperature for W-(Y0.9 La0.1)2O3 composites are identified to be 75 MPa and 1600 °C, respectively. In addition, the surface damage behavior of W-(Y0.9La0.1)2O3 composites induced by the laser thermal shock and helium ion irradiation are also investigated. It is shown that the presence of holes greatly enlarges the helium retention during helium ion irradiation and promotes the melting caused by local overheating during laser thermal shock. We find that the fine-dispersed distribution of (Y0.9La0.1)2O3 particles in the tungsten-based composites can effectively improve the resistance of helium ion irradiation and laser thermal shock. We hope that these findings could provide some guidance and reference for the fabrication of large-sized tungsten-based materials in fusion engineering.

In this article, Y2O3-reinforced tungsten composites are fabricated by using an improved wet chemical method combined with the spark plasma sintering (SPS). Triethanolamine (TEA) surfactant addition and an appropriate calcination process are innovatively introduced into this wet chemical method. The results show that ultrafine composite powders with nano-sized Y2O3 dispersions in the tungsten matrix can be obtained through the improved wet chemical method. Using the SPS, the average sizes of Y2O3 particles within tungsten grains and at grain boundaries are identified to be 13.5 and 50 nm, respectively. It is found that the phase interface between W and Y2O3 is a typical semicoherent interface. We observe that the W-Y2O3 composites possess superior mechanical properties compared with the pure tungsten counterparts. The results inferred from atomistic simulations reveal that the added Y2O3 particles can effectively pin the dislocation and impede the dislocation movement, thus enhancing the mechanical performances of W-Y2O3 composites. In addition, the addition of Y2O3 particles is also able to improve the helium ion irradiation resistance of tungsten-based composites. This study is expected to provide a certain reference for the manufacture of large-sized tungsten-based materials.

A W–0.4wt% Y2(Zr)O3 (WYZ) alloy plate with superior mechanical properties and improved high-temperature stability was prepared by hot rolling. The tensile properties of WYZ alloys with different orientations and recrystallization states were investigated at a temperature range from room temperature (RT) to 500°C. The texture intensity of the original WYZ alloy was weak, but it was significantly enhanced after annealing. The initial recrystallization temperature of the WYZ alloy was approximately 1400°C. After recrystallization annealing, the strength of the WYZ alloy decreased significantly, but it showed an increased ductility. The ultimate tensile strength and fracture elongation of the samples along the rolling direction (RD) were always significantly higher than those of the samples along the transverse direction (TD). Orientation and annealing had no evident effect on ductile-to-brittle transition temperature (DBTT) from tensile data, but increasing strain rate would overestimate DBTT. The DBTT of the WYZ alloy from tensile data was approximately between 200°C and 300°C. With the increase in tensile test temperature, the strengths of α- and γ-fiber textures on the side of fracture surface increased significantly. The increase in α- and γ-fiber texture contents was beneficial to ductility enhancement in the WYZ plate.

Extreme service environments inevitably lead to the recrystallization of tungsten. This study investigates the behavior of completely recrystallized W–Y2O3 composite materials under transient thermal shock and helium irradiation conditions based on first wall service environment. The addition of Y2O3 particles exhibits a significant effect in terms of the crack resistance of the material. After helium ion irradiation, the aggregation of fuzz structures inside the cracks becomes increasingly evident as the crack width in the thermal shock region increases. Moreover, the resistance of Y2O3 particles to irradiation damage improves as the particle size decreases. The phase interface plays an important role in the helium ions irradiation process.

The anisotropy and stability of the mechanical properties of the W alloy plate (W–0.4 wt% Y2(Zr)O3, designed as WYZ) reinforced with Y-Zr-O particles and fabricated by a wet chemical method and hot rolling were studied by compression tests. The initial recrystallization temperature of the WYZ alloy is 200 °C (about 1400 °C) higher than that of pure W with similar processes, and shows obvious increased compressive strength as well. The difference in the microstructure of various surfaces leads to evident anisotropy in the mechanical properties of the WYZ alloy. The different orientation strengths are arranged as follows: rolling direction (R-WYZ) > transverse direction (T-WYZ) > normal direction (N-WYZ). The strength of the WYZ alloy will decrease after recrystallization annealing, but the WYZ alloy annealed at 1600 °C still had an ultimate compressive strength comparable to the pure W sample with a similar preparation process. The increased compression strain rate transformed the WYZ alloy from ductile to brittle. The key factors of orientation and recrystallization influencing the compression behavior of the WYZ samples were analyzed and discussed, and the possible mechanism of the WYZ alloy reinforced with Y-Zr-O particles was also proposed.

Unhealthy dietary patterns are important risk factors for metabolic syndrome (MS), which is associated with gut microbiota disorder. High oleic acid peanut oil (HOPO) and extra virgin olive oil (EVOO), considered as healthy dietary oil, are rich in oleic acid and bioactive phytochemicals, yet efficacy of MS prevention and mechanisms linking to gut microbiota remain obscure. Herein, we investigated HOPO and EVOO supplementation in attenuating diet-induced MS, and the potential mechanisms focusing on modulation of gut microbiota. Physiological, histological and biochemical parameters and gut microbiota profiles were compared among four groups fed respectively with the following diets for 12 weeks: normal chow diet with ordinary drinking water, high-fat diet with fructose drinking water, HOPO diet with fructose drinking water, and EVOO diet with fructose drinking water. HOPO or EVOO supplementation exhibit significant lower body weight gain, homeostasis model assessment-insulin resistance (HOMA-IR), and reduced liver steatosis. HOPO significantly reduced cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL) level, while EVOO reduced these levels without significant difference. HOPO and EVOO prevented gut disorder and significantly increased &beta, diversity and abundance of Bifidobacterium. Moreover, HOPO significantly decreased abundance of Lachnospiraceae and Blautia. These findings suggest that both HOPO and EVOO can attenuate diet-induced MS, associated with modulating gut microbiota.

The piezo-phototronic effect, as a three-way coupling effect of piezoelectricity, semiconductor and optical excitation in piezoelectric semiconductors to improve the performance of optoelectronic devices, has a wide range of applications in various fields. However, under different light illumination conditions, the piezo-phototronic effect would have different effects on the optoelectronic performance due to the different photo-generated carrier excitation regions. Here, the piezo-phototronic effect is utilized to modulate the carrier transport behavior of a p-Si/n-CdS heterojunction PD during the optoelectronic process in a broadband range from visible to near-infrared light. The strain-induced piezo-charges significantly improve the photoresponse performance of the heterojunction PD. The photoresponsivity increases by 1867% under −0.35‰ strain under 808 nm light illumination, with a remarkable reduction in the rise and fall times to ∼2.1 ms (reduced by 83.3% and 50.0%, respectively). However, since the photo-generated carriers are produced only at the n-CdS side under 442 nm light illumination, the photoresponse performance is greatly weakened by the piezo-phototronic effect. The corresponding working mechanism of the piezo-phototronic effect on the heterojunction photodiode under different light illumination conditions is proposed in detail. These results provide an in-depth understanding about the piezo-phototronic effect, which would enable more efficient utilization of the piezo-phototronic effect in optoelectronic devices.

Tungsten (W) is considered as an ideal candidate matrix metal for plasma-facing materials (PFMs) in a fusion reactor owing to its high melting point and elastic modulus, high thermal conductivity and low vapor pressure, as well as low sputtering yield. However, pure W has low recrystallization temperature (RCT: 1200 ℃) and high ductile-brittle transition temperature (DBTT) which makes its low strength above RCT and poor plasticity at room temperature (RT) of pure W, thereby limiting its practical applications. In this paper, recent research progress in ODS/CDS-W alloys has been reviewed, including fabrication routes (from composite powder preparation to advanced sintering technology and then to mechanical processing) and performance assessments (mechanical properties, thermal shock behavior, hydrogen isotope retention behavior, and resistance to H/He plasma irradiation), which presents the research prospects and development directions of ODS/CDS-W alloys for fusion devices.

A series of Al-6.3Zn-2.3Mg-2.3Cu-0.15Zr alloys with different reduce of Zn, Mg, Cu and Zr were prepared by ingot-metallurgy processing. The metallurgical structure and mechanical properties were investigated by optical microscope, scanning electron microscopy and other equipment. The results indicated that the ingot’s microstructures of the four alloys contain the phrases of η (MgZn2) and θ (Al2Cu), which mostly distribute at the grain boundaries in a shape of continuous network. After extrusion processing, the grain of laser welding aluminium alloy was elongated along the extrusion direction, therefore forming fibrous structures, and meanwhile the second phase particles with different degrees of fragmentation were arranged along the extrusion direction since the microstructure of extruded bars was inherited by the as-cast structure. Zr could significantly inhibit recrystallization of alloy; the recrystallization of the alloy with lower Zr was more obvious. As the content of Zr reduced, the tensile strength of alloy decreased, but the electrical conductivity and hardness increased. When the content of Cu was lower, the hardness were decreased.

The 6xxx series aluminium alloy wires (with the diameters of 2.84 mm) produced by the continuous drawing and rotary-wheel continuous casting, were directly aged in different conditions. The results show that, when ageing temperature is at 150°C, the tensile strength of the wire firstly decreased from 283 MPa to 265 MPa as the ageing time extended from 0 to 4 hours, and then increased from 265 MPa to 270 MPa as the ageing time extended from 4 to 12 hours, and finally decreased from 270 MPa 263 MPa as the ageing time extended from 12 to 24 hours. The electrical resistively of the wires continued decreases with the ageing time extend from 0 to 24 hours. When the ageing temperature is at 160, 170, 180 and 190 °C, both the tensile strength and the electrical resistively of the wire continuously decreased with the ageing time extended from 0 to 24 hours. When the ageing time was identical, the wires with higher ageing temperature possessed lower tensile strength and electrical resistively.

The effects of final forging temperatures on deformability and structure evolution of high purity aluminum during multi-directional forging process were investigated. The results showed that increasing the initial forging temperature is beneficial for controlling the sample shape in the initial forging passes. Recrystallization during the initial forging passes improves the deformability of the sample in the following low-temperature forging processes. An X-shape fine grain zone is formed in the sample due to the inhomogeneous deformation of multi-directional forging process. When the forging pass is 6, the final forging temperature has an important influence on the grain size in the fine grain zone. The grain size decreases from 302 μm to 60 μm with the final forging temperature decreasing from 310 °C to 65 °C. The X-shape fine grain zone caused by the inhomogeneous deformation cannot be eliminated by increasing the final forging temperature (even higher than the recrystallization temperature of high purity aluminium).

A series of Al-6.3Zn-2.3Mg-2.3Cu-0.15Zr alloys with different reduce of Zn, Mg, Cu and Zr were prepared by ingot-metallurgy processing. Effects of homogenization on the microstructure and properties of Al-Zn-Mg-Cu-Zr aluminium alloy were respectively studied by means of metallographic microscopy, electrical conductivity test, differential thermal analysis and X-ray diffraction phase analysis. The results indicated that the overheating temperature of these alloys is between 473°C and 477°C, and there was little difference to the overheating temperature of 7050 alloy. During homogenization process, using three kinds of developed heat treatment of homogenization of 7050 alloy, with the rising of homogenization temperature and the complication of the homogenization heat treatment, the electrical conductivity decreased and hardness gradually increased. The three-step homogenization has a better effect than single homogenization, as it can completely eliminate the endothermic peak of non-equilibrium phases. Many MgZn2 phases are present in the ingot with three-step homogenization and slow cooling.

High density polyethylene (HDPE) with moderate content of crosslink network (CPE) was successfully prepared through chemical method. Specimens for structural characterization have been molded by conventional injection molding (CIM) and pressure vibration injection molding (PVIM). Influence of crosslink network on hierarchical morphology distribution and mechanical properties was systematically studied. Polarized light microscopy (PLM) revealed that both CIM and PVIM PE samples have a typical “skin-core” structure and the thickness of shear layer of CIM PE and PVIM CPE samples obviously increase. Scanning electron microscopy (SEM) showed that shish-kebab structures are clearly observed in shear layer of CIM CPE sample, indicating that the crosslink network can surely improve the formation of shish-kebab structures. Moreover, we suppose that shish-kebab structures emerged in shear and core layer of PVIM CPE sample. Wideangle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS) confirmed that more orientation and shish-kebab structures form even in core layer of PVIM CPE sample, which demonstrated that the hierarchical morphology was apparently altered by periodical shear and crosslink network. Finally, the mechanical properties revealed that this oriented structure increase the tensile strength from 31 MPa of CIM PE sample to 46 MPa of PVIM CPE sample. However, the tensile behavior tended to change from ductile fracture to brittle fracture.

Complementary and integrative medicine (CIM) has been used for improving health-related quality of life (HRQOL) in patients with cancer. The objective of this review is to evaluate the effects of CIMs on the HRQOL of cancer patients. We identified randomized controlled trials (RCTs) involving patients with cancer at any stage by retrieving electronic databases from the inception to February 14, 2018 (Systematic Review Registration: PROSPERO CRD42018091609). The main outcomes were HRQOL scores and related domains such as physical well-being scores. The standardized mean difference was used for the analysis and heterogeneity was assessed with the I2 statistic. A Bayesian framework was used to estimate the ranking order of efficacy in HRQOL change. Finally, 34 RCTs with 3,010 patients were included. As a whole, the results showed clearly superior efficacy of CIM in improving HRQOL. For different domains of HRQOL, different CIM interventions may play different roles. The ranking order of efficacy in change HRQOL was qigong plus mindfulness, Chinese herbal medicine, multimodal complementary medicine, qigong, nutritional supplement, mindfulness, acupuncture, yoga, and massage, and it was different among different domains. There was no evidence of publication bias. In conclusion, CIM may improve the HRQOL of cancer patients. More studies, especially focusing on male cancer patients, are needed to increase the confidence level of our findings.

A purity of 99.995% high purity aluminum was deformed by multi-forging with different conditions (forged by different forging passes with and without water cooling). The effect of multi-forging on macrostructure and mechanical property of the high purity aluminum was investigated. The results show that the deformation heat during the MDF process can obviously affect the recrystallization of the high purity aluminum. Recrystallization occurs in the easy deformation zone of the sample as forged by 3 passes at room temperature. While, when the sample are cooling by water for each pass, no recrystallization occurs in the whole sample as forged by 9 passes. When the high purity forged at room temperature, the structure difference between the easy deformation zone and stagnant zone can not be eliminated by increasing the forging pass to 9. While, the area of the recrystal grain extends with increment of the forging pass.

Eye opening, a natural and timed event during animal development, influences cortical circuit assembly and maturation; yet, little is known about its precise effect on inhibitory synaptic connections. Here we show that coinciding with eye opening, the strength of unitary inhibitory postsynaptic currents (uIPSCs) from somatostatin-expressing interneurons (SST-INs) to nearby excitatory neurons, but not interneurons, sharply decreases in layer 2/3 of the mouse visual cortex. In contrast, the strength of uIPSCs from fast-spiking interneurons (FS-INs) to excitatory neurons significantly increases during eye opening. More importantly, these developmental changes can be prevented by dark rearing or binocular lid suture, and reproduced by artificial opening of sutured lids. Mechanistically, this differential maturation of synaptic transmission is accompanied by a significant change in the postsynaptic quantal size. Together, our study reveals a differential regulation in GABAergic circuits in the cortex driven by eye opening likely crucial for cortical maturation and function.

5183 welding wire micro-alloyed using Sc, Zr, Er and automatic MIG welding system applied to weld 7A52 aluminum alloy. Optical microscope and universal tensile testing machine utilized to investigate microstructure and tensile property of welded joint, respectively. The results indicated that welded zone and fused zone was composed of uniform isometric crystal and tiny isometric dendrite crystal when the welded joint was fabricated by using 5183 welding wire micro-alloyed via rare earth element, respectively. Tensile strength and specific elongation of welded zone was improved utmostly when the 5183 welding wire micro-alloyed treatment via single Sc or Zr, respectively. Owing to mirco-alloyed treatment of 5183 welding wire by using Sc, Zr or Er, a large number of Al3Sc, Al3Zr, Al3Er granules had generated in micro-poll, which played heterogeneous nucleation role and refined microstructure of welded zone. Meanwhile, there emerged nanoscaled A13Sc, A13Zr, Al3Er strengthening phase dispersed in welded zone, which had led welded joint to exhibit exclent tensile strength.

In this paper, according to the actual students management work in the school, and link to the student attendance work, we propose one design of the B/S structure system of student attendance management based on the Java EE framework. The system realizes performances such as request and approval leave online, students' attendance data summarize, and others which reduce the workload of student management and improve the working efficiency. With the rapid development of mobile network on campus, this system also has carried on the development of mobile terminal, to further expand the scope of application of the system with the desktop of the student management system transplantation.

7A52 aluminum alloy was welded by using 5356 welding wire added Sc, Zr and Er. Microstructure of the welding joint was observed by using optical microscope (OM). Bending property was tested by bending tester. The results demonstrated that, compared to employ traditional 5356 welding wire, the grains in welding zone (WZ) were much finer; The grains in fused zone (FZ) nucleated and grew from the matrix; The grain size along heat affected zone (HAZ) dercearsed gradually.The welding joint prepared by using 5356 welding wire added single 0.3%Sc possessed maxium face bending strength. The welding joint fabricated by using 5356 welding wire added compond 0.1%Sc+0.2% Er possessed maxium rear bending strength. The fine isometric crystal and isometric dendrite generated at the welding zone when the new type 5356 wire added gingle Sc or compound Sc+Er was employed, which make the welding joint represent excellent bending property, respectively.

In this study, a purity of 99.995percent high purity aluminum was multi-directionally forged up to a maximum cumulative strain of 4.5 at room temperature. The macro and micro structure evolution in the multi-directionally forge process was investigated by structure observations and hardness measurements. The results show that the inhomogeneous deformation of multi-directional forging results in that the structure and hardness is quite different between the easy deformation zone and stagnant zone. Dynamic recrystallization occurs in easy deformation zone of high purity aluminum sample at room temperature as the cumulative true strain is 1.5 (3 forging passes), while the structure in the stagnant zone is still not recrystallizated even at a cumulative true strain of 4.5 (9 forging passes). The recrystallized grain size in the easy deformation zone is reduced with the number of forging passes, and the area of recrystallize grains increase with the number of forging passes.

Al-Mg welding wires applied extensively in aluminum alloy welding field.5183 ingot and 5356 ingot added Sc, Zr and Er were fabricated by DC casting method and extruded into welding wire, furtherly. Surfacing layer on 7A52 aluminum alloy prepared by using automatic surfacing formation system. Optical microscopy (OM) and 1600-5122VD MICROMET 5104 micro-hardness tester utilized to observe microstructure of 5183 and 5356 ingots, to measure micro-hardness of surfacing layer fabricated by using 5183 and 5356 welding wire with Sc, Zr, Er addition, respectively. The results indicated that, owing to addition of rare earth element, re-crystallization of Al-Mg extruded ingot to generate welding wire was restrained markedly; Microstructure was refined obviously when Sc added; And average size of the grains was about 10μm. Micro-hardness of surfacing layer improved after addition of Sc, Zr, Er element in the ingots.

Environmental risks pertaining to contaminated soils have been well studied, while little attention has been paid to the risks of the soils after remediation. In this study, a concept model developed based on fuzzy set theory was applied to evaluate the uncertainties of three risk indicators, namely, plant growth, groundwater safety and human health, of a restored site that had been previously polluted by heavy metals. The concept model classified the grade and importance of risk factors by an 11-level ranking system and was able to yield a comprehensive risk result rather than multi-risk results for complex risk indicators. Modeling results showed that the risks to the three indicators were effectively reduced after the remediation. Moreover, great sensitivity of the risks was found related to the weight distribution among the three risk indicators. In general, the risks of both polluted and restored soils to the environment were in the order of groundwater safety > plant growth > human health. The model was proved to solve the problems of multi-risk results due to complex risk indicators that previously encountered by other researchers, which made it helpful in decision-making and management of restored soils.

The magnetic field interference was studied by numerical simulation and experimental examination during dual-ingot low-frequency electromagnetic casting process. By using ANSYS software package to mesh and compute, the magnetic field distribution of semi-continuous casting mold region was simulated. The calculated results were verified with the experimental ones and the effects of current direction, shield, silicon sheet and the coil distance on the distribution of magnetic field and ingot were observed. The result indicated that: regardless of current direction, the magnetic field interference among coils appears and the magnetic flux density weakens in the neighbor part of coils. When the current direction of adjacent coils is opposite, the magnetic intensity in ingots is stronger than that of in the same direction. As the distance between coils increases, the magnetic field reduction generated by interference decreases. The magnetic field interference can be alleviated by setting silicon steel sheets or shield.

The big earthquake is a sudden, devastating natural disasters, and cause great harm to social.Earthquake damage to the structure of the building is the main reason to cause personal injury.Therefore, seismic research is particularly important.With further research,seismic studies from traditional seismic structure gradually developed into the base isolation,and the basis of isolation to become a major research focus.Although many studies of base isolation structure,But for foundation isolation in limit structure research is not enough, and not paid enough attention to practical engineering.Therefore, based on the theory of structural dynamics, create a calculation model, preparation of the limit protective isolation structure analysis procedures, and validation analysis Limit Protection Isolation structure can better analyze dynamic schedule.

2024 Al alloy ingot with diameter of 100 mm is produced by conventional and combined electromagnetic fields (CEMF) horizontal direction chill (HDC) casting processes. The effect of CEMF on the ingot structure is investigated. The results show that the CEMF is effective in changing the inner structure of the 2024 HDC cast ingot. In the conventional HDC ingot, feathery grains mainly distribute over the majority of the area of the ingot, and coarse equiaxed grains mixed with coarse floating grains distribute in a crescent-shaped area near the bottom surface. With the application of the CEMF, the majority of the feathery grains transform to fine equiaxed grains, and the mixture of feathery and fine grains only exist in the area near the upper surface. In addition, the coarse floating grains completely disappeared in the ingot with the application of CEMF.

Commercial aluminum ingot with the diameters of 100 mm is produced by conventional out-phase electromagnetic field HDC casting process. The out-phase electromagnetic field is applied on the HDC casting process. The effect of out-phase electromagnetic filed on the ingot surface and structure is investigated. The result shows that the out-phase electromagnetic field is more effective in improving the upper surface, while, has little function on the bottom surface. The macro/microstructure of the ingot is changed by the out-phase electromagnetic field. Very long and coarse columnar grains evolve to short and thin columnar grains with the application of the out-phase electromagnetic field.

Complex chemical composition is an important reason for restricting herbal quality evaluation. Despite the multi-components determination method significantly promoted the progress of herbal quality evaluation, however, which mainly concerned the total amount of multiple components and ignored the activity variation between each one, and did not accurately reflect the biological activity of botanical medicines. In this manuscript, we proposed a toxicity calibrated contents determination method for hyper toxic aconite, called toxic constituents index (TCI). Initially, we determined the minimum lethal dose value of mesaconitine (MA), aconitine (AC), and hypaconitine (HA), and established the equation TCI = 100 × (0.3387 ×X MA + 0.4778 ×X AC + 0.1835 ×X HA). Then, 10 batches of aconite were selected and their evaluation results of toxic potency (TP), diester diterpenoid alkaloids (DDAs), and TCI were compared. Linear regression analysis result suggested that the relevance between TCI and TP was the highest and the correlation coefficient R was 0.954. Prediction error values study also indicated that the evaluation results of TCI was highly consistent with that of TP. Moreover, TCI and DDAs were both applied to evaluate 14 batches of aconite samples oriented different origins; from the different evaluation results, we found when the proportion of HA was reached 25% in DDAs, the pharmacopeia method could generate false positive results. All these results testified the accuracy and universality of TCI method. We believe that this study method is rather accurate, simple, and easy operation and it will be of great utility in studies of other foods and herbs.