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To increase crops yields, applying large amounts of fertilizers has become increasingly common in agricultural regions, resulting in NO

Sugar content and composition are critical to fruit development. Sucrose, a photosynthate unloaded to the fruit, is metabolized by sucrose synthase, which might play a dominant role in sucrose accumulation during strawberry fruit ripening. However, substantial evidence regarding the molecular mechanism underlying sucrose accumulation in strawberry fruit development is lacking. Here, a strawberry sucrose synthase gene, FaSS1, was cloned and identified. Its 2421-bp cDNA includes an intact open reading frame and encodes an 806 amino acid protein, in which sucrose synthase-related conserved domains were predicted by a homology analysis. Using tobacco rattle virus-induced gene silencing, the downregulation of FaSS1 transcripts significantly delayed fruit ripening, as evidenced by the changes of firmness, and soluble sugar and anthocyanin contents, as well as the transcripts of several ripening-related genes, including PE1, PL1, XYL2, CHS, CHI, and DFR. Furthermore, the mRNA expression level of FaSS1 was inhibited by abscisic acid or sucrose, but not by glucose after fruit disc incubation in vitro. In conclusion, FaSS1 plays an important role in the regulation of strawberry fruit ripening, and its expression could be inhibited by abscisic acid and sucrose.

To clarify the microbial pathway of the N以北京地区白菜地为研究对象进行肥料试验,结合乙炔抑制试验设置有机肥乙炔组、有机肥无乙炔组、无机肥(尿素)乙炔组、无机肥无乙炔组4个处理,利用N

To understand the mechanisms of agricultural N以华北平原菜地为研究对象,通过控制灌溉量设置不同的土壤水分对照,利用稳定同位素

Background: Recent studies have shown that vitiligo is a T-cell mediated autoimmune disease. Skin-homing cytotoxic T lymphocytes expressing cutaneous lymphocyte-associated antigen (CLA) have been suggested to be responsible for the destruction of melanocytes in vitiligo. An aberration in the suppressive function of regulatory T cells (Tregs) has been reported in vitiligo patients. However, whether the weakened suppressive ability of the Tregs contributes to hyper-activated skin homing CD8+CLA+ T cells remains to be determined. Objectives: To investigate the inhibition of circulating Tregs on the proliferation of autologous CD8+CLA+ T cells in non-segmental vitiligo patients. Methods: CD8+CLA+ T cells and Tregs were obtained from the peripheral blood of 13 non-segmental vitiligo patients and 7 controls. The proliferative responses of CD8+CLA+ T cells were assessed in the absence or presence of autologous Tregs, and the levels of Transforming Growth Factor β1(TGF-β1) and IL-10 in culture supernatants were detected by enzyme-linked immunosorbent assay. Results: The proliferative responses of circulating CD8+CLA+ T cells in the presence of Tregs were significantly higher in the active vitiligo than in the stable vitiligo and control groups. Tregs from active vitiligo patients exhibited a lower inhibitory effect on proliferation of CD8+CLA+ T cells. The levels of TGF-β1 produced by Tregs were significantly lower in active vitiligo than other groups and anti-TGF-β1 antibodies could abrogate the suppressive function of Tregs. Conclusions: The functional activity of Tregs is compromised in active vitiligo patients. TGF-β1 plays an important role in the autoimmune mechanism of the disease.

Much progress has been made toward understanding plant drought resistance. However, the coordinate responses of plant to drought on the basis of ABA level at physiological, ecological and molecular levels remains unclear. Here, the potted winter wheat (triticum aestivum) was cultivated under relative soil moisture (RSM ) respectively at 85% (well-watered), 65% (moderate stress), and 45% (severe stress), and a series of physiological and ecological parameters including ABA level, stomatal conductance, leaf temperature, leaf water potential, together with transcripts of ABA biosynthesis-metabolism key genes including9-cis-epoxycarotenoid dioxygenase(TaNCED),ABA glucosyltransferase(TaGT),ABA8'-hydroxylase(TaCYP707A), andβ-glucosidase(TaBG) were carried out. We found that ABA contents responsive to soil water loss increased rapidly and showed a significantly-negative correlation with the stomatal conductance and the leaf water potential and a significantly-positive correlation with the leaf-air temperature difference, respectively. The continuous accumulation of ABA was resulted mainly from the increased transcripts of bothTaNCEDsandTaBGsgenes. The transcripts ofTaCYP707A1andTaGTdeclined sharply from 85% to 65% RSM and then increased slightly from 65% to 45% RSM, indicating that ABA metabolism not only accelerates the accumulation of ABA level but also contributes to maintain ABA homeostasis. In conclusion, the macroscopic-microscopic changes responsive to water deficient reflects the ABA-regulated, drought-resistance coordinate mechanisms at physiological, ecological and molecular levels intriticum aestivum.

Although much progress has been made towards understanding the ripening of non-climacteric fruit using the strawberry as a model plant, the defined molecular mechanisms remain unclear. Here, RNA-sequencing was performed using four cDNA libraries around the onset of ripening, and a total of 31,793 unigenes and 335 pathways were annotated including the top five pathways, which were involved in ribosome, spliceosome, protein processing, plant-pathogen interaction and plant hormone signaling, and the important DEGs related to ripening were annotated to be mainly involved in protein translation and processing, sugar metabolism, energy metabolism, phytohormones, antioxidation, pigment and softening, especially finding a decreased trend of oxidative phosphorylation during red-coloring. VIGS-mediated downregulation of the pyruvate dehydrogenase gene PDHE1α, a key gene for glycolysis-derived oxidative phosphorylation, could inhibit respiration and ATP biosynthesis, whilst promote the accumulation of sugar, ABA, ETH, and PA, ultimately accelerating the ripening. In conclusion, our results demonstrate that a set of metabolism transition occurred during green-to-white-to-red stages that are coupled with more-to-less DEGs, and the oxidative phosphorylation plays an important role in the regulation of ripening. On the basis of our results, we discuss an oxidative phosphorylation-based model underlying strawberry fruit ripening.

Information on the relationship between crop photosynthetic rate and water use efficiency at the leaf level and these at the canopy level is important on the study of theory and practice of high efficiency and water-saving agriculture. We simultaneous made instantaneous CO2 and H2O exchange rate, and instantaneous water use efficiency measurement at both leaf and canopy level in a rain-fed cropping system with spring corn during filling stage by Li-6400 infrared gas analysis meter and eddy correlation system. The results showed that in arid area water stress was the mainly factor influencing the net photosynthesis rate and water use efficiency. At the diurnal course, when soil relative moisture was about 40% at 0-100 cm soil layer, the maximum of net photosynthetic rate at leaf level occurred at about 10:00 under soil water stress, and at about 12:00 at canopy level on sunny days, the maximum leaf photosynthetic rate reached 1.3 mgm-2s-1 , almost close to those of irrigation corn at similar latitude area, and the maximum canopy assimilation rate were 0.9 mgm-2s-1 , reached 54.5% of those of irrigation corn at similar latitude area during filling stage, respectively;The maximum values of instantaneous water use efficiency at leaf and canopy level were 0.16 g (CO2)/ g (H2O) and 0.06 g (CO2)/ g (H2O), and ranged between 0.0055g (CO2)/ g (H2O) and 0.0123 g (CO2)/ g (H2O), 0.0113 g (CO2)/ g (H2O) and 0.0197 g (CO2)/ g (H2O) around noon, respectively. Instantaneous net photosynthetic rate and water use efficiency at leaf level were higher than those at canopy level after 10:00.

The combustion of paper mill sludge and bituminous coal in air was analyzed using a thermogravimetric instrument. TG and DTG curves for the blends lies between that of the individual fuels, and the main combustion characteristics of blends depended on individual fuels and followed the weighted average. As the blending ratio of paper mill sludge was increased from 10% to 90%, the ignite temperature (Ti) decreased from 529.6°C. to 275.6°C., and residual weight increased from 19.28% to 47.39%. The TG profiles of sample were almost the same at different heating rates, however there was a big difference between the DTG profiles. The maximum weight loss rate of sample increased obviously with the increment of heating rate. This work contributes to the comprehensive understanding of paper mill sludge and bituminous coal combustion and development of co-combustion technology.

The study of Priestley-Taylor (PT) reference crop evapotranspiration model coefficient (α) in local is of great significance in semi-arid agricultural water resources efficient use and precision irrigation in corn. Here, based on the FAO (1998)-recommended Penman-Monteith (PM) reference crop evapotranspiration as a standard method, water and heat exchange and its estimated parameters were determined by eddy covariance technique and Priestley-Taylor model under local climatic conditions. The results indicated that the estimated values of reference crop evapotranspiration (ET0-PT 1.26) in gained by PT mode-recommended coefficient (α = 1.26) lowed by 21.2% during non-growth stages (from November to April next year), and reached an average of 5.5% above PM model reference crop evapotranspiration (ET0-PM) during May to September. The local PT model coefficient α value was 1.15 ± 0.06. The gained average PT mode coefficient at noon during growth stages showed a peak trend with the highest value 0.67 ± 0.08 at tasseling to flowering stage and with the lowest value 0.26 ± 0.13 at seedling stage. In conclusion, the reference crop evapotranspiration estimated accurately by PT mode in the semi-arid climate area, a local PT parameter is required to gain firstly.

Dry-land spring maize is a main cultivated crop in North-West China. To explore the mechanism for changes of evapotranspiration and heat consumption in dry-land spring maize, eddy covariance technique was used to monitor the energy-exchange characteristics of the crop in Eastern Loess Plateau field. The results showed that the field-energy-balance ratio of dry-land spring maize is in the 0.75 - 1.0 range during non-rainfall daily noon (12:00 - 14:00). The Bowen ratio exhibited "L-type" trend during the total growth stages, namely, the highest Bowen ratio was at seedling stage with phase average 4.85 ± 1.42. The evaporation fraction showed a single peak trend in August, and the higher evaporation ratio met with more precipitation with average values 0.55 ± 0.06. The Bowen ratio and average evaporation fraction at the entire growth period were 1.78 ± 1.71 and 0.40 ± 0.18, respectively. About 40% of surface energy obtained from drought agro-ecosystem was used for evapotranspiration and heat consumption.

A modified denitrifier method on Tracegas-isotope ratio mass spectrometry (IRMS) was developed to determine the nitrogen and oxygen isotopic compositions of nitrate (NO3-) in water samples. The protocol presented in our previous publication was modified in several aspects. Then, the incubation time, amount of NO3-sample, and effect of trapping time in the Tracegas system were analyzed using the standard reference USGS34. Both δ15N and δ18O values demonstrated accurate and reproducible at incubation times exceeding 12 h or overnight as well as added 0.2 μg to 0.4 μg NO3--N samples. Our data also showed that 100 s for trapping time in Tracegas system was adequate to achieve accurate and reproducible results. Finally, the δ15N and δ18O values of nitrate in animal wastewater were measured using this method. The results indicate that the denitrifier method can be used widely for tracing nitrate sources and controlling nitrate contamination in China.

The surface quality of graphite cannot be completely evaluated only by the roughness value Ra measured by profilometer. The surface damage ratio Sc is presented to give quantitative description of surface quality of graphite, which was calculated as the ratio of the projection area of fracture craters to the overall area of free surface. The machined surface was observed and taken photo by use of the stereo microscope with CCD image acquisition system. Matlab image processing tool was used to convert the color photo to binary image, in which fracture craters were shown as black pixels and the other surfaces as white pixels. The surface damage ratio is the result of the sum of black pixels divided by the overall pixels. Under the same conditions of high speed machining experiments for verification, the surface damage ratio was calculated in comparison with the Ra values measured by profilometer. The variation tendency of surface damage ratios exhibited good coherence to the measured roughness.

CNC machine tools and programming is a professional core curriculum of the vocational colleges in machinery manufacturing and automation, and CNC machining technology. This course involves teaching and professional practice, which requires us to improve teaching methods, improve the quality of teaching to promote students 'understanding of CNC machine tools and programming course and mastery, in order to develop students' practical capacity. In this paper, we use the conception, design, implementation, and operation of the CDIO model implementation of teaching reform, providing engineering teaching model with a new teaching ideas, and this also plays an active role in the training to cultivate innovative talents.

Temperature measurement methods always including contact method and non-contact method, generally speaking, non-contact method used for detecting remote measuring objects temperature, in especially as to particular occasions such as factory workshop. This paper provides a system based FPGA(field programmable gate array)for accurate measure and analysis long distance objects temperature. The system could be used in process of industrial produce fabrication.

In this essay, the surface microstructure of infiltration casting of low-carbon ductile iron was studied in detail. The results show that the micro hardness from the cast infiltration layer to the matrix zone increased at first and then decreased, the maximum micro hardness was about HV1400, maternal surface hardness are greatly enhanced. Low carbon ductile iron can obtain good surface microstructure by using casting infiltration technology. The hardness of alloy layer on low carbon ductile iron matrix is greatly improved.

The industrial effluents produced in petrochemical production contain kinds of pollutants and fluctuate wildly, also lead sewage plant to be impacted frequently. It is significant to develop a method that warms the effluents quality early, efficiently and accurately. As a result, it can make the biochemical devices run and manage smoothly. Based on the extreme sensitivity of Oxygen Uptake Rate (OUR) and Dehydrogenase Activity (DHA) to the abnormal effluents and toxicants, this study proposed a comprehensive assessment method of biodegradability and biotoxicity with Specific Oxygen Uptake Rate (SOUR) and Specific Dehydrogenase Activity (SDHA). And it also discussed the biodegradability and biotoxicity of the industrial effluents with different pH and toxicant by detecting OUR, SOUR and DHA. The results showed that, these three indexes were extremely sensitive and accurate to the effluents quality change. And the maximum concentrations of phenol, formaldehyde and carbinol that the microorganisms can allow in the industrial effluents were 350mg/L, 70mg/L and 170 mg/L. When the sewage plant was functioning normally, SOUR and SDHA fluctuations were 3.0~7.0 and 1.0~4.0 respectively. Therefore, they have important application value and prospect to early warming in the effluents quality.

Organic farming is a good way to reduce environmental pollution. However, no related detection of fertilizer applications, which are extremely important in organic farming, exists. The δ15N value of chemical fertilizer (–3.8 to +2‰) is far lower than compost (>+10‰). Thus, natural 15N abundance (δ15N) in leaves and fruits may be used to reveal the application of N fertilizer. In this experiment, six treatments were laid out: 635 g (C1), 952 g (C2), and 1270 g (C3) of compost were applied as basal fertilizer in each pot. Alternately, 10.7 g (U1), 16 g (U2), and 21.3 g (U3) of urea were applied as basal fertilizer and 10.7 g (U1), 16 g (U2), and 21.3 g (U3) urea were applied as top-dressing, respectively, in each pot. C1 and U1, C2 and U2, and C3 and U3 had equal amounts of nitrogen fertilization. In all three fertilizer levels, the leaves and fruits sampled from the U group had significantly lower values than those sampled from the C group within the same period. The δ15N values of the leaves and fruits from the C group decreased slowly. The δ15N values of leaves sampled at 40 days after transplanting were fairly low. The δ15N values of leaves and fruits from the U group increased initially, due to the small amounts of urea left, which then led the plants to absorb N from the culture substrates. However, the δ15N values of leaves and fruits from the U group decreased rapidly after the top-dressing was applied, where the minimum values occurred during the final stage.

Based on the electric hot method has been applied to turning effectively, this paper analyzes electrical properties of the electric hot cutting micro area, according to contact resistance theory the electrical conduction model of cutting micro area is established, electric hot method applied to minipore drilling of hard-to-cut materials is discussed, it develops a set of electric hot drilling device which is simple and flexible. Under the conditions of the same drilling parameters, electric hot drilling tests and ordinary drilling hole experiment are researched contrastively. Test results show that axial force and torque of electric hot drilling experiment are reduced obviously than that of ordinary drilling holes experiment. Electric heating method applied in drilling process is very effective.

Based on the electric hot drilling and ordinary drilling to drill small hole for hard-to-cut materials stainless steel, the chip morphology and microstructure were studied, the cutting deformation coefficient of the ordinary drilling is bigger, and the chip is not easy to discharge from spiral groove, while the cutting deformation coefficient of electric hot drilling is small, the chips are discharged smoothly along the spiral groove, experimental results show that the electric heating drilling improves capacity of chip breaking, and reduces drill fracture result from the chip obstruction, so it improves the service life of the drill bit.

In the essay, the Low carbon ductile iron by laser surface alloying processing has been experimentally studied. Results indicate that on low carbon ductile iron matrix coated with different alloy powder, structure of laser surface alloying processing is very small, the combination quality between alloying layer and matrix is good. Low carbon ductile iron after laser surface treatment, maternal surface hardness are greatly enhanced, maternal surface hardness increasing from HV250~330 to the highest about HV1400, surface laser hardening effect of Low carbon ductile iron is very obvious.

Based on a large number of CO2 laser welding tests to hard alloy saw blade cutter by PHC-1300 type laser of 1300W and TEM00 mode, and the laser welding parameters and weld microstructures were analyzed ,the mechanical performance tests were also done. The experimental results show that CO2 laser welding can improve combination strength and bearing capacity of the hard alloy circular saw blade cutter; the laser focal spot offset a distance from the weld line to the center of basal body, which can get the optimal weld line; selecting low carbon alloy steel as matrix material and selecting Co-based alloy as knife head lining material are suitable.

Based on a large number of welding tests to automotive lightweight material by CO2 laser, the microstructures of welded joint were tested related to performance. on the condition of welding technology, the relationship between the lower critical power of stabile deep penetration welding and welding speed and the focus position is deduced, In a coaxial and side protective gas conditions, through the optimization of technological parameters laser deep penetration welding can effectively avoid heat affected zone of high strength zinc coated steel becomes soft, welded comprehensive quality has been effectively controlled. Zinc evaporates unsteadily, which leads to expansion of heat affected zone and reduction of welding stability, so in this paper effective measures are taken to control it. Experimental results show that a qualified welding quality can be obtained by optimized process parameters of laser welding and adopting argon as shielding gas.

This paper analyzes the influence of cutting parameter to temperature in high speed milling high manganese steel process. By measuring tool-workpiece interface temperature and analyzing temperature distribution in the workpiece, the experimental results show that maximum temperature on tool surface increases with the increase of spindle speed, while the temperature of the total workpiece increases little in the cutting process. Temperature variation law of tool-workpiece interface and total workpiece are matched with the traditional processing mechanism well.

Closed-Loop PLM is the development direction of product management in the future. Network platform is the indispensable means for realizing closed-loop. It could be concluded that the Internet Things can be the network platform of C-L PLM by analyzing the circulation data, data distribution, and hardware and software configuration. The connection method of EPCglobal network and C-L PLM was designed, based on analyzing them belonging to the same standard frame.

QuEChERS is an acetonitrile partitioning and dispersive solid-phase extraction (D-SPE) method that widely used in the analysis of multiple classes of pesticide residues in vegetable and fruit. In this paper, we modified it to fulfill analysis on much more complex matrix-Chinese herbal medicine, and High Performance Liquid Chromatography-Mass Spectrometry (HPLC-MS) was chosen for analysis. This method could be applied to quantitative and qualitative analysis of a wide range of pesticides in Chinese herbal medicine (Fructus Aurantii Immaturus as sample).

Soil quality monitoring is important in precision agriculture. This study aimed to examine the possibility of assessing the soil parameters in apple-growing regions using spectroscopic methods. A total of 111 soil samples were collected from 11 typical sites of apple orchards, and the croplands surrounding them. Near-infrared (NIR) and mid-infrared (MIR) spectra, combined with partial least square regression, were used to predict the soil parameters, including organic matter (OM) content, pH, and the contents of As, Cu, Zn, Pb, and Cr. Organic matter and pH were closely correlated with As and the heavy metals. The NIR model showed a high prediction accuracy for the determination of OM, pH, and As, with correlation coefficients (r) of 0.89, 0.89, and 0.90, respectively. The predictions of these three parameters by MIR showed reduced accuracy, with r values of 0.77, 0.84, and 0.92, respectively. The heavy metals could also be measured by spectroscopy due to their correlation with organic matter. Both NIR and MIR had high correlation coefficients for the determination of Cu, Zn, and Cr, with standard errors of prediction of 2.95, 10.48, and 9.49 mg kg−1 for NIR and 3.69, 5.84, and 6.94 mg kg−1 for MIR, respectively. Pb content behaved differently from the other parameters. Both NIR and MIR underestimated Pb content, with r values of 0.67 and 0.56 and standard errors of prediction of 3.46 and 2.99, respectively. Cu and Zn had a higher correlation with OM and pH and were better predicted than Pb and Cr. Thus, NIR spectra could accurately predict several soil parameters, metallic and nonmetallic, simultaneously, and were more feasible than MIR in analyzing soil parameters in the study area.

Ca3(VO4)2: Eu3+, Bi3+ phosphor powders were prepared by the combustion synthesis or the solid state reaction at room temperature, respectively. The phase composition, morphology and photo-luminescence of the Ca3(VO4)2: Eu3+, Bi3+ phosphors were investigated by X-ray diffraction, scanning electron microscope, and spectrophotometry, respectively. The results show that the Ca3(VO4)2: Eu3+, Bi3+ powder prepared by the combustion synthesis is claviform, while the Ca3(VO4)2: Eu3+, Bi3+ powder directly obtained by the solid state reaction at room temperature is orbicular. The discrepancy in emission is attributed to the variation in the Eu3+ morphology of in powders.

Based on quasi-stable state heat-transfer control mode, finite difference equation of thermal conductivity in laser welding is deduced. Physical parameter (specific heat) substitutes for phase-changing latent heat, then critical temperature of thermal conductivity welding is determined, so finite difference equation can be solved by MATLAB software. Temperature field distribution is simulated to weldment.Influence of technological parameters such as laser power and welding speed on temperature field are investigated systematically by numerical simulation, these can establish theoretical basis for optimization of technological parameters in laser welding.

The milling process of hard-to-cut material high manganese steel ZGMn13 was simulated and experimental studied based on Johnson-Cook material model and shear failure model.The high speed milling processing finite element model has established adopting arbitrary Lagrangian-Euler method (ALE) and the grid adaptive technology,The influence of milling parameters to milling force is analyzed in the high speed milling high manganese steel process. The simulated and experimental results being discussed are matched well. It certifies the finite element model is correct.

A novel red emitting phosphor, Ca2SnO4: Eu3+, was prepared by the low temperature solid state reaction. X-ray powder diffraction (XRD) analysis confirmed the formation of Ca2SnO4: Eu3+. Scanning electron-microscopy (SEM) observation indicated a narrow size distribution of about 500 nm for the particles with spherical shape. Under 396 nm excitation, the Ca2SnO4: Eu3+ phosphor exhibits novel red emission at about 613 nm which is assigned to the 5D0→7F2 electric-dipole transition. Furthermore, the emission transition 5D0→7F2 has been found to be more prominent over the normal orange emission transition 5D0→7F1.

Based on many experiments of CO2 laser welding of high strength two-sided galvanized steel thick with 1.5mm to vehicle body, joint microstructure and stress-strain curves of specimen are acquired. It has inferred theoretically relations among critical power, welding speed and focal point position under given welding technological conditions. With coaxial and side-blown protective gas, craft parameter are optimized, the laser deep melt welding may avoid effectively heat-affected zone (HAZ) softened phenomenon, as well as welded porosity may controlled effectively. The experimental result shows that hardness value in weld zone becomes low with increasing of energy input, at the same time the cracked zone of tensile specimen, the dimple size and the distribution of cross-section in welding seam are also different, tensile crack of welding seam extends to the base metal, which indicates deep penetration laser welding can effectively avoid softening of welding joints during laser welding of high strength galvanized steel.

Malfunction prediction is a trend of NC machine tool malfunction diagnosis development and the diagnosis accuracy is heavily dependent on the real and online acquisition of malfunction parameters. Gear malfunction is one of main mechanical malfunctions, and it is very meaningful to forecast its malfunction. The shock vibration of gear malfunction is non-stationary, so it should be processed by time frequency algorithms. Kalman filtering and Laplace wavelet are time frequency algorithms. Klaman filtering is self-adapting algorithm, and can filter noise in real-time. Laplace wavelet can obtain malfunction parameters by correlation filtering when correlation parameter k is the maximum. The proposed technique features two appealing advantages, which include self-adapting Kalman filter-based time-frequency algorithm and a Laplace wavelet-based parameters extraction. A set of simulating gear vibration data was used for verification. It provides a quantitative and more efficient means for obtaining the malfunction parameters to malfunction forecasting system.

The key point for improving efficiency of Electric Hot Machining (EHM) is to keep an optimal heating temperature in cutting process. This paper introduces the principle and system for realizing optimal heating current control, Electric Hot Machining is applied to minipore drill of hard-material, a method of rapid determining the optimal heating current under various cutting conditions in electric hot drilling is proposed based on the conservation law of optimum cutting temperature. For a certain combination of tool and workpiece, the heating current in different cutting conditions can be obtained by changing heating current and measuring the cutting temperature in electric hot drilling.

Micro carbide endmills suffer severe abrasive friction and impact wear in high speed milling of graphite. This paper focused on the study of the effect of Co content and WC grain size on the tool wear resistance of micro carbide endmills in high speed milling of graphite. The tool wear morphologies of cutting tools were examined at the initial wear stage and severe wear stage. The results showed that the abrasive resistance of micro carbide endmill increased with the decrease of Co content and WC grain size. The best impact resistance can be obtained with medium Co content and smaller WC grain size. The fine-grained carbide 0.2WC-8%Co is considered as the optimum tool material for high speed milling of graphite.

Manufacturing resources model is the most important part of virtual manufacturing. This study demonstrates the information expressing model of manufacturing resources, which can be separated into virtual control model, real model and functional model of virtual manufacturing devices. The study also indicates the relationship among three parts and presents the modeling methods.

Phospholipase D (PLD) hydrolyzes structural phospholipids of biological membrane to produce phosphatidic acid (PA) and a free-head group. Both of these compounds can participate in signal transduction. Since the activation of PLD involved in many cellular signaling cascades was identified in recent years, knowledge of and interest in PLD have grown greatly, and significant progress has been made toward understanding PLD. This paper reviewed the research progress on gene structure, regulation and cellular function of PLD. PLDs are encoded by a multiple heterogenous gene family. The overall domain structures of plant PLDs are similar, but important differences occur in some of the motifs. The small structural variations underlie distinct regulatory and catalytic properties and cellular function in signaling. PA and other messengers produced by other phospholipase pathways can be interconverted with the action of lipid kinase and phosphatase. PLD is thought to function as an integral part of a network involving other lipid-signaling enzymes and messengers. Some research evidence demonstrated the specificity of PLDs in signal transduction with plant species, cell types, stimuli and cellular processes. Some important questions about PLD study were also raised.