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Solvothermal subcomponent self-assembly of 2-hydroxy-3-(pyridin-4-yl)benzaldehyde, chiral diaminocyclohexane, and Zn(ii) ions offered a pair of two-dimensional chiral metal–organic frameworks, which display circularly polarised luminescence.

Water oxidation to molecular oxygen is indispensable but a challenge for splitting H2O. In this work, a series of Co-based metal-organic cages (MOCs) for photoinduced water oxidation were prepared. MOC-1 with both bis(μ-oxo) bridged dicobalt and Co-O (O from H2O) displays catalytic activity with an initial oxygen evolution rate of 80.4 mmol/g/h and a TOF of 7.49 × 10-3 s-1 in 10 min. In contrast, MOC-2 containing only Co-O (O from H2O) in the structure results in a lower oxygen evolution rate (40.8 mmol/g/h, 4.78 × 10-3 s-1), while the amount of oxygen evolved from the solution of MOC-4 without both active sites is undetectable. Isotope experiments with or without H218O as the reactant successfully demonstrate that the molecular oxygen was produced from water oxidation. Photophysical and electrochemical studies reveal that photoinduced water oxidation initializes via electron transfer from the excited [Ru(bpy)3]2+* to Na2S2O8, and then, the cobalt active sites further donate electrons to the oxidized [Ru(bpy)3]3+ to drive water oxidation. This proof-of-concept study indicates that MOCs can work as potential efficient catalysts for photoinduced water oxidation.

A unique metal-organic framework (MOF) with tetrazole-padded helical channels has been successfully synthesized in one pot from iron(II) trifluoromethanesulfonate, 4-formylimidazole, hydrazine, and sodium azide under solvothermal conditions and features a rare unh topology and porous structure for gas adsorption. Transformations of condensation, cycloaddition, and coordination occurred during the synthetic process, in which a 1,5-disubstituted tetrazole ligand was formed in situ.

As a creation platform for multifunctional materials, crystalline metal–organic frameworks (MOFs) can integrate different chromophores through reticular chemistry to adjust their spatial arrangement and intermolecular interaction, in turn achieving the purpose of improving the nature of optoelectronic properties. Herein, a stepwise reticular synthesis approach is successfully used to construct a multicomponent MOF, in which the well-known bis-terpyridyl ruthenium chromophore is orderly arranged into the skeleton of the material. Remarkably, this method promotes the excited state lifetime of the bis-terpyridyl ruthenium core, by two orders of magnitude (from 0.39 to 22.09 ns), to the extent that it can produce singlet oxygen under visible light irradiation at room temperature. Meanwhile, the obtained multicomponent MOF has been established to have considerable porosity for exposure of substrates to the catalytic sites, rendering it suitable for heterogeneous photocatalysis, including as a photooxidation detoxifier for sulfur mustard simulant. Moreover, DFT and TDDFT calculations reveal that the synergistic charge transfer among different components in the MOF may play a crucial role in improving the excited state properties of the bis-terpyridyl ruthenium motif.

A triangular prismatic metal-organic cage based on mixed valence copper ions has been designed and synthesized by using metallocycle panels and pillar ligands. The triangular prism will be quickly transformed to a 10-nuclear cage upon an external chemical stimulus, which features a bicapped square antiprism structure. This prismatic cage can act as a catalyst for oxidation of aromatic alcohols to their corresponding aromatic aldehydes with high yields at room temperature under O2 atmosphere.

Two mixed-valence CuII/CuI and two heterometallic CuII/AgI metallocycles have been synthesized by the assembly of designed metalloligands and CuI/AgI ions, respectively. The CuII/CuI metallocycle can catalyze the oxidation of alcohols to aldehydes mediated by a co-catalyst, TEMPO (2,2,6,6-tetramethylpiperdine-1-oxyl), with ambient air as an oxidant, while the CuII/AgI metallocycle has no catalytic effect.

Gas separation performances are usually degraded under humid conditions for many crystalline porous materials because of the lack of water stability and/or the competition of water vapor toward the interaction sites (e.g., open metal sites). Zeolitic imidazolate frameworks (ZIFs) are suitable candidates for practical applications in gas separation because of their excellent physical/chemical stabilities. However, the limitation of substituent positions in common ZIFs has prevented extensive pore engineering to improve their separation performance. In a type of gyroidal ZIFs with

This review summarizes experimental evidence indicating that subcutaneous mast cells are involved in the trigger mechanism of analgesia induced by acupuncture, a traditional oriental therapy, which has gradually become accepted worldwide. The results are essentially based on work from our laboratories. Skin mast cells are present at a high density in acupuncture points where fine needles are inserted and manipulated during acupuncture intervention. Mast cells are sensitive to mechanical stimulation because they express multiple types of mechanosensitive channels, including TRPV1, TRPV2, TRPV4, receptors and chloride channels. Acupuncture manipulation generates force and torque that indirectly activate the mast cells via the collagen network. Subsequently, various mediators, for example, histamine, serotonin, adenosine triphosphate and adenosine, are released from activated mast cells to the interstitial space; they or their downstream products activate the corresponding receptors situated at local nerve terminals of sensory neurons in peripheral ganglia. The analgesic effects are thought to be generated via the reduced electrical activities of the primary sensory neurons. Alternatively, these neurons project such signals to pain-relevant regions in spinal cord and/or higher centers of the brain.

The SiF62- anions are in situ formed in the reactions of MF2 (M = Cu2+, Zn2+, Ni2+, and Co2+) salts and nitrogen-containing ligands in borosilicate glass tubes under solvothermal conditions and then used to further construct a family of metal-organic frameworks (MOFs). This in situ reaction demonstrates a new and facile strategy for the fabrication of MOFs based on SiF62-.

A family of polyhedral metal-imidazolate cages based on the flexible bi-imidazole ligand L and Cu2+ ions have been synthesized and characterized, featuring an unusual Cu10L8 bicapped square antiprism structure (or Johnson solids, J17) with an adaptable cavity. These metal–organic cages encapsulate anions, and they will expand or compress after they are filled with different-sized anions.

In this study, Mg-12Zn magnesium alloys alloyed with Al additions (0, 2, 4, 6, 8 and 10, wt.%) were fabricated by permanent mould casting. The Al content on their microstructure and mechanical properties were systematically examined with an optical microscope (OM), a scanning electron microscope (SEM), an X-ray diffractometer (XRD) and mechanical tests at room temperature. The experimental results indicate that the microstructure of the alloys is mainly composed of α-Mg and semi-continuous or continuous eutectic phases. A higher addition of Al (≥6%) causes the generation of the Mg17Al12 phases. Notably, the grain sizes of the alloys gradually decrease, whilst the partial morphology of some eutectic phases is modified into lamellar structure with increasing of Al addition. Mechanical properties characterization manifested that, the alloys with different Al additions reveal distinguishing tensile properties. Among them, the alloy with 4% Al provides an excellent mechanical properties, i.e., a UTS of 206 MPa and an EL of 7.92%, which is respectively higher 28 MPa and 1.08% than that of ZA120 alloy. The deterioration in the tensile properties for the higher Al-bearing alloys is possibly related to the lamellar structure, coarse and continuous net-work morphology and β-Mg17Al12 phases, respectively.

In contrast to the regular postsynthetic modification (PSM) approach which is global and random in principle, a diffusion-controlled PSM strategy utilizing size mismatch between pores and reactants has been developed to target selective functionalization and fine-tuning of material performance. Demonstrating through narrow-pore ZIF-90 reacting with amines of contrasting aliphatic chain lengths, we manage to regulate the extent and distribution of hydrophobic functionalization, and to judiciously tune the hydrophobicity of the crystalline materials. A subtle balance between reagent dose, water tolerance enhancement, and maintenance of gas adsorption performance has been achieved. ZIF-90 crystallites are imparted with surface hydrophobicity by only 1% aliphatic modification of ligands, while its hydrothermal stability is enhanced by 5% aliphatic modification, owing to the coverage of the vulnerable mesopore regions in the overall structure. Moreover, such low-dose PSM avoids severe pore blockage which would result in significant repellence of gas/vapor adsorbates (e.g. N2, CO2, H2O), as also predicted by ideal adsorbed solution theory (IAST), showing largely unaffected CO2/N2 and CO2/CH4 separation performance. This proposed spatially-differentiated strategy provides a facile route to implementing diffusion-limited PSM processes to fabricate core–shell-like MOFs.

On the basis of stack augmented electromagnetic rail launcher, using an H type armature to connect the upper and lower two groups of guideways through four contact surfaces to form an electromagnetic rail launcher. By changing the shape of the contact surface of the armature and the guide rail, different launcher models were set up, and compared with the traditional augmented electromagnetic launchers. The simulation analysis was carried out by Maxwell software. The results show that the electromagnetic thrust of the H type armature is obviously greater than that of the double-armature. For the arc shaped contact surface, the current distribution on the contact surface of the double-armature is the most uniform, and the ablation and melting can be well suppressed. The current distribution on the contact surface of the H type armature is more uniform and has the greatest electromagnetic thrust, so it is more suitable electromagnetic rail launch.

Phosphorescence/fluorescence hybrid white organic light-emitting diodes (OLEDs) are highly appealing for solid-state lighting. One major challenge is how to fully utilize the electrically generated excitons for light output. Herein, an efficient strategy to realize full exciton radiation is successfully revealed by a judicious molecular design and suitable device engineering. A blue host emitter TP-PPI is designed and synthesized, exhibiting a near 100% photoluminescence quantum yield and a high triplet energy level, enabling high-performance blue fluorescence and sensitization of a yellow phosphorescent dopant. Full exciton radiation in hybrid white OLEDs is demonstrated with a single emitting layer formed by doping a yellow phosphor (PO-01) into TP-PPI. Near 100% exciton utilization and state-of-the-art external quantum efficiency of 27.5% are achieved with the high-efficiency blue-emitting host and an electron-trap engineered device architecture.

This study aimed to characterize the diagnostic and vaccine potential of a novel Mycobacterium tuberculosis antigen Rv0674.To evaluate the diagnostic potential and antigenicity of Rv0674, IgG was evaluated using ELISA and interferon (IFN)-γ was done by using ELISpot assay among TB patients and healthy donors. For immunogenicity evaluation, BALB/c mice were immunized with Rv0674. Cytokine production was determined by cytokine release assay using an ELISA kit, and the antibodies were tested using ELISA.The results of serum Elisa tests showed that Rv0674 specific immunoglobulin G (IgG) response was higher in TB patients than negative controls. And Rv0674 had good performance in serological test with sensitivity and specificity of 77.1% and 81.1%, respectively. While it shows poor sensitivity and specificity of 26.23% and 79.69% for IFN-γ tests. In BALB/c mice, Rv0674 adjuvant by DDA/Poly I:C could also induce a high level of IFN-γ, interleukin-2 and interleukin-6 as well as a high IgG titer in both high- and low-dose groups indicating that Rv0674 is essential in humoral and cellular immunity. Moreover, the cytokine profile and IgG isotype characterized Rv0674 as a Th1/Th2-mixed-type protective immunity with the predominance of Th1 cytokines.Rv0674 may be a good potential candidate for the development of TB serological diagnosis and a new TB vaccine.

To investigate the effect of Li2O, K2O and ZnO on SiO2-Al2O3-B2O3-Na2O vitrified bond for CBN grinding wheels, the refractoriness and fluidity of specimens with different additions were studied. The bending strength was measured by three-point bending tester and the microstructures were observed by super Depth-of-Field microscope. The results show that Li2O, K2O and ZnO can reduce the refractoriness and increase the high-temperature fluidity. Li2O and K2O make a contribution to improving the bending strength; however ZnO is harmful to specimens’ mechanical property. Additionally, the fluidity is important to control the number of gas bubbles in specimen according to the microstructure analysis.

Grinding is applied widely in manufacturing of high-precision component. And, pursuing the forming mechanism, together with predicting topography characteristics and roughness of the grinding surface, is becoming more and more important in improving the grinding quality. The grinding surface is formed by the interaction between the grinding wheel and the workpiece. And, its topography is influenced by the grain shape, grinding wheel surface topography, and machining parameters. In this paper, the study started from establishing the topography of wheel surface. And, according to grinding kinematics, the grain trajectory equations were established. By applying the statistical screening methods, the actual cutting depth was determined. Then, the grinding surface topography was formed by simulating. Considering the influence of vibration in actual grinding, the surface topography of the workpiece under forced vibration was studied. The study results showed that the influence of grinding speed was significant for grinding surface topography, mainly in the influence for amplitude and frequency. Finally, the grinding experiments were used to verify the results of the simulation. The obtained experimental results confirmed that the as-proposed method worked efficiently and rapidly in simulating the grinding surface topography and predicting the grinding surface roughness.

As the central component of rotating machine, the performance reliability assessment and remaining useful lifetime prediction of bearing are of crucial importance in condition-based maintenance to reduce the maintenance cost and improve the reliability. A prognostic algorithm to assess the reliability and forecast the remaining useful lifetime (RUL) of bearings was proposed, consisting of three phases. Online vibration and temperature signals of bearings in normal state were measured during the manufacturing process and the most useful time-dependent features of vibration signals were extracted based on correlation analysis (feature selection step). Time series analysis based on neural network, as an identification model, was used to predict the features of bearing vibration signals at any horizons (feature prediction step). Furthermore, according to the features, degradation factor was defined. The proportional hazard model was generated to estimate the survival function and forecast the RUL of the bearing (RUL prediction step). The positive results show that the plausibility and effectiveness of the proposed approach can facilitate bearing reliability estimation and RUL prediction.

Chiral coordination cages feature both chirality and defined inner space, providing advanced molecular materials. A series of chiral 20-nucleus cobalt-imidazolate cages were synthesized by self-assembly of 72 subcomponents, featuring a novel tetartoid (tetragonal pentagonal dodecahedron) structure. Spontaneous resolution of racemic tetartoidal cages (Δ and Λ) into a conglomerate of homochiral crystals are observed, while both homochiral Δ and Λ tetartoidal cages can be obtained through chiral induction of (d)- and (l)-enantiomers of menthol, respectively. The 2-methyl substituent on imidazolyl is critical to the formation of a tetartoidal cage, and the absence of such steric effect will switch the final structure to a cubic cage.

OBJECTIVE: To investigate the efficacy of ACEI drugs in the treatment of hypertension patients and the effect of two levels of prevention of hypertension complicated with coronary heart disease and stroke. METHODS: 210 cases of hypertension patients in our hospital from January 2012 to December 2015 were randomly divided into experimental group and control group, 105 cases in each group. According to the conventional symptomatic treatment, the experimental group was given lisinopril treatment, while control group was given the captopril treatment. Changes of blood pressure parameters and the level of baPWV in two groups were observed before and after treatment coronary heart disease and stroke, recurrence rate and death rate were compared in these two groups. RESULTS: No significant difference of SBP, DBP, PP and baPWV between two groups before treatment (P > 0.05). The indexes of the two groups were significantly decreased after 1 months and 3 months, and the level of patients in the experimental group was lower than that of the control group (P < 0.05). The recurrence rate in the experimental group was lower than those in the control group (P < 0.05). CONCLUSIONS: ACEI drugs in the treatment of hypertension can effectively reduce the level of blood pressure, improve arterial elasticity function, reduce the recurrence rate and mortality rate of coronary heart disease and stroke. The effect of antihypertensive and two levels of prevention of hypertension complicated with coronary heart disease and stroke of lisinopril is positive.

This study aims to explore the correlation between X-linked inhibitor of apoptosis protein (XIAP) gene polymorphisms (rs8371 and rs9856) with the susceptibility and prognosis of esophageal squamous cell carcinoma (ESCC), providing a potential treatment for ESCC.A total of 170 ESCC patients (case group) and 191 healthy people (control group) were enrolled in our study. Genotyping was conducted on the basis of the ligase detection reaction (LDR). The expressions of XIAP polymorphisms were detected. The patients were followed up every three months until death or the last follow-up day. The overall survival (OS) and progression free survival (PFS) were recorded by Kaplan-Meier survival curve, and the relationship between XIAP gene polymorphism and risk and prognosis of ESCC was assessed by Cox multivariate analysis.TT+CT genotype and T allele frequencies of XIAP rs8371 and rs9856 in the case group were significantly lower compared to those of the control group (all P0.05), suggesting that TT+CT genotype of XIAP rs8371 and rs9856 was associated with ESCC susceptibility. XIAP rs8371 and rs9856 polymorphisms were associated with tumor node metastasis (TNM) staging, depth of invasion and lymph node metastasis. The OS and PFS of TT+CT genotype carriers of rs8371 were longer than those of CC genotype carriers. Smoking, alcohol, TNM staging, depth of invasion, and lymph node metastasis were significantly associated with the OS and PFS in ESCC patients. Higher TNM staging, depth of invasion, and presence of lymph node metastasis were independent risk factors, while XIAP rs8371 was an independent protective factor for the prognosis of ESCC patients.The present study demonstrates that XIAP rs8371 and rs9856 are associated with susceptibility to ESCC, and rs8371 polymorphisms might serve as an indicator for improved clinical efficacy and prognosis of ESCC patients.

Background Gastric cancer remains one of the leading cause of death in the world. Drug combinations are potential approaches to provide more efficient treatments that minimize side effects. Purpose We investigated the pharmacological effects of the combination of wogonin with oxaliplatin on gastric cancer cells in vitro and in vivo. Methods and Results In the present study, we found that wogonin enhanced the cytotoxicity of oxaliplatin; the drug combination resulted in strong synergistic inhibition of the cell viability in BGC-823 cells and in a zebrafish xenograft model. Interestingly, the combined treatment of wogonin and oxaliplatin modulated the expression of phospho-JNK (Thr183/Tyr185), phospho-ULK1 (Ser555) and the formation of LC3II. Confocal imaging data consistently showed that wogonin exacerbates the oxaliplatin-induced dissipation of the mitochondrial membrane potential (ΔΨm) and formation of peroxynitrite in BGC-823 cells. Moreover, wogonin allows a reduction in oxaliplatin dose when they are combined; therefore, it is a relevant strategy for reducing the side effects of oxaliplatin while achieving the same response. Conclusion These results suggest that wogonin can be a potential therapeutic candidate for enhancing the efficacy of oxaliplatin in gastric cancer treatment.

In order to control the speed of hydraulic cylinder precisely through a given voltage signal on proportional valve, we adopt the pressure compensator and proportional directional valves throttle circuit in the hydraulic feed system of the designing coal and rock cutting test equipment. The simulation model of the system based on AMESim is built, the dynamic characteristic on the feed system of proportional valve-controlled cylinder’s speed is analyzed, experiments under no-loading condition on the hydraulic pump station is done. Simulation and experimental results show that the cylinder’s speed can be controlled precisely through a given voltage signal on proportional valve, the experimental and simulation results are close, which can better meet the test requirements of coal and rock cutting. Finally the sorting curves of the cylinder’s speed varies with the proportional valve opening can provide the basis of cutting parameters of coal and rock cutting test equipment.

To study the mechanical property of concrete column confined by GFRP, we conducted 6 groups of specimens under axial compress. The influences of GFRP wind mode and layers were taken into account. According to the results, bearing capacity and ductility of the spiral winding specimen was improved greatly. The bearing capacity of the 6° spiral winding concrete column’s improvement is 28%, more than it of 0°. The fiber polymer’s utilization ratio can be improved greatly when column were combined with all spiral wind. Strengthen the concrete column of ±15°cross spiral winding pretend to be stronger capacity of bearing axial press than it of 6° spiral winding, but limiting strain tends to be lower. Shearing crack often happens at the 45°of the specimen, so shearing failure can be prevented effectively by GFRP (45°).Effective deformation and strength can be provided by FRP at the direction of axial and circular, and the reinforcing steel bar in concrete column can be substituted partially.

More attention has been paid on the technology of BFRP in civil engineering due to it’s unique properties, such as high strength-to-weight radio, good resistance to corrosion and convenient to construction. In order to study the properties of BFRP sheets confined concrete column ,we did it through three groups of columns subjected to axial loading tests and FEM analyses, mainly considering the effect of spacing of straps of BFRP sheets confining concrete column.The results shows that the axial compressive strength and ductility of concrete column winded by BFRP straps have all increased and the process of destruction of concrete column wrapped by BFRP is longer than that of the unconfined concrete column.

Polyaniline nanorods, nanoplates and urchin-like structures have been synthesized successfully by the template-free method of aniline and peroxo–polytungstic acid using ammonium persulphate as the oxidant in aqueous solution. The peroxo–polytungstic acid concentration and reaction temperature play important role in the formation process of polyaniline nanostructures. As the precursor concentration increased to 0.29mol/L, nanorods and urchin structures were obtained. With the decrease of temperature, the amount of PANI nanoplates with radially aligned dendritic surface structures will increase. The radially aligned dendritic surface is probably due to the molecular structures of the dopant, the linear nature of PANI chains and the second nucleation formation.

In the micro EDM method by electrostatic induction feeding, a pulse voltage source is coupled to the tool electrode by a capacitor in order to reduce the minimum discharge energy per pulse. Positive pulse voltage and negative pulse voltage are applied to the tool electrode alternately, relative to the workpiece. In this study, it was found that when the feeding capacitance was large, multiple discharges occurred frequently during a single pulse duration of the pulse voltage source. Since the impedance of the pulse voltage source which was produced by the authors varied depending on the polarity, the multiple discharges occurred in the polarity with the higher impedance, while they did not occur in the opposite polarity. It was also found that when multiple discharges occurred, the discharge energy was released intermittently in the multiple discharges. In this study, using multiple discharges phenomena, better surface was obtained with higher removal speed.

The carrying of Liquid hybrid bearing for ultra-high speed grinding is complex. The oil film temperature distribution in different input state is obtained through CFD analysis by FLUENT. On this basis, the temperature characteristics laws of the oil film with the input parameters change were obtained. Analysis shows that the relationships of oil film temperature with spindle speed and eccentricity are directly proportional and super linear, the relationship of oil film temperature with oil supply pressure is inverse ratio and the relationship with oil supply temperature is approximation directly proportional to the linear. Finally the significant of the various input parameters are analyzed through the orthogonal test. The results show that the effect of spindle speed is most significantly.

Discrete complex method is used in genetic algorithm(GA) and a mixed genetic algorithm called complex genetic algorithm(CGA) is formed. The complex method used here increases the quality of species groups, and improves the searching efficiency. The mixed genetic algorithm method is used in the shape optimization for mixed discrete variables. The integration and coding of the shape variables and the cross-section variables in genetic algorithm can not only solve the coupling problem of two kinds of variables, but also avoid the partial optimum solution resulting from the separation of the two kinds of variables. The result of the exemplification indicates that the complex genetic algorithm for structure shape optimization design of mixed discrete variables is effective.

Analysis on the characters of ground subsidence of Yangjiaping mining area, with same excavation depth and recovery coefficient, the numerical simulations to nonlinear large deformation using finite-difference method(FLAC) are achieved on the different strip extraction schemes that adopted different mining and reservation width. The result indicates that the subsidence values and horizontal deformation increases with the increasing of the strip extraction width on condition of the same recovery rate. Based on probability density function (PDF) method, the relationship of the coal pillar width, the mining width and ground deformation is acquired, which is some useful reference for using the strip extraction method to control the surface movement and deformation.

In order to perfectly reflect the dynamic corrosion of reinforced concrete (RC) cover in practical engineering, an analytic model of non-uniform corrosion induced cracking was presented based on the elastic-plastic fracture mechanics theory. Comparisons with the published experimental data show that the predictions given by the present model are in good agreement with the results both for natural exposed experiments and short-time indoor tests (the best difference is about 2.7%). Also it obviously provides much better precision than those models under the assumption of uniform corrosion (the maximal improved precision is about 48%). Therefore, it is pointed out that the so-called uniform corrosion models to describe the cover cracking of RC should be adopted cautiously. Finally, the influences of thickness of local rusty layer around the reinforcing steel bar on the critical corrosion-induced crack indexes were investigated. It is found that the thickness of local rusty layer has great effect on the critical mass loss of reinforcing steel, threshold expansion pressure, and time to cover cracking. For local rusty layer thickness with a size of a = 0.5 mm, the time to cover cracking will increase by about one times when a/b (a, semi-minor axis; b, semi-major axis) changes from 0.1 to 1 mm.

The wedge splitting test specimens with three series of different relative crack length were used to study the influences of relative crack length on the fracture toughness of common concrete. The suitable formulation for fracture toughness of concrete with different relative crack length was gotten on comparing between fracture toughness test results and computation results of the model developed from Hu formula.

Grinding temperature is an important parameter in affecting the quality of grinding. The higher grinding temperature would cause thermal damage to workpiece. But in the actual grinding processing, it is difficult to measure the grinding temperature in real time. This paper presents the finite difference method to calculate the grinding temperature. When calculating the grinding temperature, an important physical quantity cannot be avoided; it is the energy partition and it is the fraction of the grinding energy transported as heat to the workpiece at the grinding zone. At present, there are a lot of calculation models for the energy distribution, but no one is very exact, and most models are exclusive for alumina grinding wheel grinding. Based on measuring the grinding force and temperature, the heat flux toward the workpiece can be back-calculated by finite difference method that compared the difference between the thermal model and experimental results; thus, the energy partition can be obtained. The results show that it provides a 3D graphic image of the whole temperature field by using the fused deposition modeling (FDM). And the influences of feed rate on grinding temperature and of energy partition are significant compared with the grinding speed and depth of cut. The improvement of feed rate can effectively reduce the grinding temperature, but energy partition has a significant rise. After repeated research, an approximate value of energy partition was obtained by using vitrified bond cubic boron nitride (CBN) wheel grinding titanium alloy material TC4, and it was about 5 % under dry grinding.

Bovine adenovirus type 3 (BAV-3) is considered one of the most important respiratory tract agents of cattle and is widespread among cattle around the world. A BAV-3 strain was isolated from a bovine nasal swab for the first time in China in 2009 and named HLJ0955. Subsequently, BAV-3 has frequently been isolated from calves with respiratory diseases in China. To date, only limited study on the pathogenesis of BAV-3 infection in cotton rats has been conducted, and the pathogenesis of BAV-3 infection in guinea pigs has not been reported. Therefore, sixteen albino guinea pigs were inoculated intranasally with HLJ0955. All of the infected guinea pigs had apparently elevated rectal temperatures (39.2 °C-39.9 °C) at 2-7 days post-inoculation (PI). Consolidation and petechial hemorrhage were also observed in guinea pigs experimentally infected with HLJ0955. Viral replication was detectable by virus isolation and titration and by immunohistochemistry in the lungs of guinea pigs as early as 24 h PI. Viral DNA was detectable in the lungs of infected guinea pigs during 11 days of observation by real-time PCR. Virus-neutralizing antibodies against BAV-3 were detectable from 11 days PI and reached a peak titer at 15 days PI. Histopathological changes mainly occurred in the lungs of infected guinea pigs and were characterized by thickening of alveolar septa, mononuclear cell infiltration, hemorrhage and alveolar epithelial necrosis. These results indicate that HLJ0955 can replicate in the lungs of guinea pigs and cause fever and gross and histological lesions. The guinea pig infection model of BAV-3 would serve as a useful system for monitoring the infection process and pathogenesis of the Chinese BAV-3 strain HLJ0955, as well as immune responses to BAV-3 vaccines.

Bovine parainfluenza virus type 3 (BPIV3) is one of the most important of the known viral respiratory tract agents of both young and adult cattle and widespread among cattle around the world. Up to present, three genotypes A, B and C of BPIV3 have been described on the basis of genetic and phylogenetic analysis and only limited studies on the pathogenesis of the genotype A of BPIV3 infection in calves and laboratory animals have been performed. The report about experimental infections of the genotypes B and C of BPIV3 in laboratory animals and calves was scant. Therefore, an experimental infection of guinea pigs with the Chinese BPIV3 strain SD0835 of the genotype C was performed. Sixteen guinea pigs were intranasally inoculated with the suspension of SD0835, while eight control guinea pigs were also intranasally inoculated with the same volume of supernatant from uninfected MDBK cells. The virus-inoculated guinea pigs displayed a few observable clinical signs that were related to the respiratory tract disease and two of the sixteen experimentally infected guinea pigs died at 2 and 3 days post inoculation (PI), respectively, and apparent gross pneumonic lesions were observed at necropsy. The gross pneumonic lesions in guinea pigs inoculated with SD0835 consisted of dark red, slightly depressed, irregular areas of consolidation in the lung lobes from the second to 9th day of infection at necropsy, and almost complete consolidation and atelectasis of the lung lobes were seen at 7 days PI. Histopathological changes including alveoli septa thickening and focal cellulose pneumonia were also observed in the lungs of guinea pigs experimentally infected with SD0835. Viral replication was detectable by virus isolation and titration, real-time RT-PCR and immunohistochemistry (IHC) staining in the respiratory tissues of guinea pigs as early as 24h after intranasal inoculation with SD0835. The results of virus isolation and titration showed that guinea pigs were permissive for SD0835 replication and exhibited a higher virus replication level in both lungs and tracheas. As well, the results of IHC staining implicated that the lungs and tracheas were the major tissues in which SD0835 replicated. Virus-specific serum neutralizing antibodies against BPIV3 were detected in virus-inoculated guinea pigs. The aforementioned results indicated that BPIV3 strain SD0835 of the genotype C was pathogenic to guinea pigs and could cause a few observable clinical signs, and gross and histologic lesions in virus-inoculated guinea pigs. Thus guinea pig is an ideal laboratory animal infection model for BPIV3 and would cast more light on the genotype C of BPIV3 infection process, in vivo tropism and pathogenesis or serve as a useful system for monitoring the pathogenesis of SD0835 and other BPIV3 isolates.

Field survey and site study were conducted to approach the process and causes of salinization-alkalization of Leymus chinensis grassland in Songnen Plain, and to examine the hypothesis of soil disturbance-bareness. In the grassland, surface soil (0-30 cm) had a lower salt content, while deeper soil (30 cm) was in adverse. Thereby, the grassland was defined as soil-salted grassland. There was an increasing salt content in surface soil. This process was called as soil salinization-alkalization, and the grassland under the salinization:alkalization was named as alkali-salinized grassland. The leading reason for the surface soil salinization-alkalization was that the surface soil originally with low salt content was disturbed and lost away, subsurface soil rich in salt emerged as new surface soil, and the salt in deeper soil layers accumulated in the new surface soil and other soil layers. Secondary halophyte communities formed on the surface-soil-disturbed new bare land, but the communities had no succession sequence. The degradation process of the grassland was soil degradation first, followed by vegetation degradation, halophyte invasion, and successive evolution from nearly primitive condition.

Owing to the weak local searching power and slow iteration in the Genetic Algorithm, some strategies such as optimum individual conservation, infeasible individual transformation and local hesitation strategies are used to improve the Genetic Algorithm. when structure shape optimization design of mixed discrete variables is conducted, if the shape variables are continuous and the cross-section variables are discrete, this two kinds of variables should be considered comprehensively. And two-step searching strategies are put forward. The two-step strategies means that in the early stage of evolution, rough searching is carried through the whole searching range, the searching range is reduced to the adjacency of the optimum solution and then local fine searching is done in the late stage of evolution, thus the searching process is accelerated. The result of the exemplification indicates that the Genetic Algorithm for structure shape optimization design of mixed discrete variables is effective.