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To ensure the quality of heavy plate products as determined by ultrasonic inspection, it is necessary to effectively control defects such as cracks and shrinkage cavities in heavy plates. Generally, some defects such as large size cracks exist due to insufficient deformation in the center of traditionally rolled plates. Compared with the traditional rolling process, gradient temperature rolling (GTR) process can effectively increase deformation inside heavy plates. In this study, the effect of GTR on crack healing was analyzed through a comparison experiment with the uniform temperature rolling (UTR). The results show that the GTR process could increase the plastic strain inside the heavy plate and effectively promote the healing process of the preset cracks. The degrees of crack healing at the center and quarter thickness position of the steel plate via GTR were greater than twice those of the plate via UTR. The GTR process can significantly reduce the internal defects of heavy plates and improve the defect detection level of heavy plate products. Also, The GTR process results in the formation of new crystal grains in the crack region, which is crucial to crack healing.

After digesting the relevant domestic and foreign literature and tracking the concerns of fresh agricultural products by business entities, consumers, and relevant experts and scholars in each area of fresh agricultural products, combining fresh agricultural products and agricultural development, this article discusses agricultural economic benefits and logistics quality factors. Three aspects of the industrial market structure are used to construct an evaluation index system for the logistics level of fresh agricultural products. Taking Sichuan Province as the research object, the gray correlation model is used to analyze the main factors affecting the logistics level of fresh agricultural products, and at the same time, a correlation analysis is used to further analyze the correlation of each influencing factor. The article systemically analyzes the main influencing factors, and puts forward development suggestions from multiple aspects to promote the development of agriculture.

Nickel-aluminium bronze (NAB) alloys are traditional marine materials used for decades, but face to the challenge of insufficient strength and corrosion properties. In this work, thanks to the strong solid solution strengthening, corrosion and biofouling resistant ability of multiple components, we developed novel NiMnFeCrAlCu multi-principal-element alloys (MPEAs), which exhibit excellent combination of mechanical and corrosion resistant properties. It was found that NiMnFe0.5Cr0.5Al0.2Cu1.2 MPEA has higher yield and ultimate tensile strength, and lower corrosion current density by one magnitude than those of NBA, and also shows a considerable copper ion release concentration. These merits are attributed to the dual phase of FCC+BCC, and the enrichment of Cu in the FCC matrix and Cr in the BCC grains. This work has implication in the new strategy for the development of advanced marine materials.

Phenolic compounds and total antioxidant activities were analysed in five green asparagus cultivars (Grande, Altas, UC800, UC301 and UC157). In addition, the colours as well as the lignin, amino acid, and microelement contents of the asparagus cultivars were assessed. Cultivar ‘Grande’ had the best greenness (a*=-12.47), the highest vitamin C (59.1 mg/kg) and microelement contents (282.3 mg/kg) and the lowest lignin content (0.92%). Cultivar ‘UC301’ had the highest amino acid content (3.95 g/kg), and cultivar ‘UC157’ had the highest total phenolic and total flavonoid contents. Correlations were determined to evaluate the relationship between phenolic compounds and total antioxidant activity. Phenolic compounds, particularly rutin, are major contributors to the antioxidant activity of green asparagus, with a correlation coefficient of r=0.977-0.982. A principal component analysis was then performed to investigate the interrelationships between the parameters and the investigated cultivars. The results showed that cultivars ‘UC157’ and ‘Grande’ had high total phenolic and rutin contents and consequently high antioxidant activity. The cultivar had a marked influence on bioactive constituents, particularly the phenolic compound content and composition, and on the antioxidant activity of green asparagus, which may provide a basis for improved health benefits and breeding programs.

Eight Mg 100- x - y Zn x Y y (at.%, x = 2–7.2, y = 4–7) alloys with atomic ratios of Y/Zn = 0.75–2 were designed and prepared by rapidly solidified powder metallurgy technology. The atomized powders with the Y/Zn atomic ratios larger than 1 contain α-Mg dendrite and network-like X-Mg 12 ZnY compound, but those with the Y/Zn atomic ratios of 1 and 0.75 have W-Mg 3 Zn 3 Y 2 particle besides the above two phases. After hot extrusion, network-like Mg 12 ZnY phase was changed into acicular and plate-like shape. These as-extruded alloys exhibit excellent mechanical properties at room and elevated temperature. Especially, the ultimate tensile strength of as-extruded Mg 86 Zn 7 Y 7 alloy reaches up to 541 MPa at room temperature and 297 MPa at 250 °C. HRTEM study reveals that Mg 12 ZnY phase is composed of 18R LPSO structures. These sub-micrometer Mg 3 Zn 3 Y 2 particles bring about dispersion strengthening to Mg 12 ZnY phases, resulting in a synergistic strengthening of Mg 12 ZnY phase and Mg 3 Zn 3 Y 2 particle in the alloy which has the Y/Zn atomic ratio equal to or larger than 1. Therefore, the excellent mechanical properties of Mg 86 Zn 7 Y 7 alloy are attributed to the second phase strengthening of LPSO phase and synergistic strengthening of Mg 12 ZnY phase and Mg 3 Zn 3 Y 2 particle.

Aims Development of a multiplex TaqMan RT-qPCR assay to simultaneously detect Narcissus yellow stripe virus (NYSV) and Narcissus mosaic virus (NMV), frequently causing mixed narcissus infection. Feasibility verification was confirmed in natural samples. Methods and Results Primers and probes were designed based on the conserved CP gene regions of NYSV or NMV and their suitability for singleplex and multiplex TaqMan RT-qPCR assays as well as for conventional RT-PCR. Conventional RT-PCR, singleplex and multiplex TaqMan RT-qPCR assays proved to be NYSV and NMV specific. P-values and coefficients of variation of TaqMan RT-qPCR assays indicated high reproducibility. Significantly increased sensitivity was achieved compared to conventional RT-PCR. The detection limit of both viruses was 103 copies with superior correlation coefficients and linear standard curve responses between plasmid concentrations and Ct values. NYSV and NMV infection of narcissus leaves, petals and bulbs could successfully be detected via our multiplex RT-qPCR method at 1·25 mg. Conclusion Our multiplex TaqMan RT-qPCR assay provides rapid, specific, sensitive and reliable testing to simultaneously detect NYSV and NMV, supplying useful routine monitoring for different narcissus samples. Significance and Impact of the Study Efficient identification and discrimination of the narcissus viruses provides reliable information for scientists and conventional growers. Furthermore, it enriches the information of NYSV, NMV and other narcissus viruses.

The high strength aluminum alloy tube can not be formed into complex parts for its high strength and poor plasticity at room temperature. However, its elongation increases with temperature elevating. Therefore, warm forming technology is becoming the research hotspot in aluminum alloy tube forming. However, the control requirement of exact forming temperature and the demand of accessories with high temperature resistance make process control difficult and processing cost high. Based on this point, this study puts forward a new technological process: solution treatment + granules medium internal high pressure forming + artificial aging. During this process, the tested alloy via solution treatment satisfied the process requirements and the granules medium internal high pressure forming method for high strength aluminum alloy tube was also realized by using convenient implementation with low requirement of equipment and flexible design of product. In this paper, the AA6061 extruded tube is investigated to research the effect of heat treatment on mechanical properties. At a solution temperature of 560 °C and time of 120 min, the elongation of the AA6061 extruded tube increases by 258%, the strength and the hardness dramatically decrease too. Therefore, the AA6061 tube meets the requirement of internal high pressure forming because of the improvement of formability. At an aging temperature of 180 °C and time of 360 min, the strength and hardness of AA6061 recover to the as-received alloy. The typical part of stepped shaft tube was successfully trial-produced in lab by using the present forming method. The maximum expansion ratio (MER) of the AA6061 extruded tube increases by 25%. The theoretical forming limit diagram (FLD) is also applied to analyze and predict the fracture trend of forming tube.

In this article, we present a new kind of Fe-C-B-P-Cu nanocrystalline alloys containing high P content with excellent comprehensive magnetic properties and processability. This kind of nanocrystalline alloys exhibits the high saturation magnetic flux density (Bs), low coercivity (Hc) and high effective permeability (μe) in the range of 1.73–1.84 T, 3.2–8.4 A/m and 6000–13000, respectively. It was found that increase of P content remarkably decreases the sensitivity of Hc to annealing temperature (Ta) and widen the optimum annealing temperature range to obtain a low Hc. With the increase of P content, the growth of α-Fe grains is retarded, but the nucleation of α-Fe grains is increased, resulting in reduced grain size and the intergranular amorphous layer, and precipitated high density of α-Fe nanocrystals. Based on the crystallization and structural features, the relationship between soft magnetic properties and microstructure for this kind nanocrystalline alloy was discussed in detail.

Fe 0.4 Cr 0.4 NiMn x Cu (0 ≤ x ≤ 1.4) high entropy alloys (HEAs) were prepared by copper-mold casting. The phase selection, microstructure, tensile properties and fracture morphologies were investigated. The microstructure with dual FCC phases was formed in the as-cast HEAs with x ≤ 1, and BCC phase was crystallized from the central FCC dendrites of HEAs with x = 1.2 and 1.4. In homogenized Fe 0.4 Cr 0.4 NiMnCu HEA, needle-like shaped BCC phase was formed resulting in a slight enhancement of yield strength. Compositional heterogeneity was detected in both FCC and BCC dendrites. These HEAs exhibit excellent comprehensive tensile properties, e.g . the yield strength, ultimate strength and elongation of the HEA with x = 1 reaches 439 MPa, 884 MPa and 23.4%, respectively. High density of dislocations in FCC matrix was formed after tensile deformation. FCC type of fine polyhedra, which is mainly composed of Cr, Mn and O, is formed in dendrites. In this work, the phase selection and strengthening mechanism were evaluated based on atomic size factor. It was found that two criteria can be employed to predict the phase regions of current alloys. The solid solution strengthening for this HEA system is the most important among the four kinds of strengthening mechanisms.

The corrosion behavior of Cr 40 Co 39 Nb 7 B 14 and Cr 50 Co 29 Nb 7 B 14 bulk metallic glasses in HCl solutions were investigated by immersion, electrochemical tests and microstructural observation. XPS analyses were performed to clarify chemical states of elements in the passive films. The results show that these alloys can be passive against corrosion in 1 and 3 M HCl, and high Cr content in the alloys has advantages on passivation properties. Increasing the exposure time in air and immersion time in 3 M HCl can accelerate the passivation. The high corrosion resistance is attributed to the highly-enriched trivalent Cr-oxide films formed in corrosive environments.

Dense and porous nickel-free Ti–11Nb–4O (at.%) alloys with Af temperature closed to body temperature were fabricated by conventional powder metallurgy (sintering) method from elemental Ti and Nb powders. Their microstructure, phase transformation temperature, superelasticity and mechanical properties at room temperature were investigated by optical microscopy, X-ray diffraction, differential scanning calorimetry and compression testing. It has been found that the phase temperature of Ti–11Nb–4O alloy by sintering is different from that by smelting and cold-rolling method due to the introduction of oxygen during powder mixing and sintering, and the Af temperature can reach up about 40 °C by reducing Nb content and controlling oxygen. Near dense Ti–11Nb–4O alloys can exhibit more than 5.4% superelasticity, high cyclic stability up to 100 cycles, high yield strength of 1.48 GPa and small strain hysteresis of 0.14% at room temperature. Moreover, porous Ti–11Nb–4O alloys with 29.4% porosity also can show complete superelasticity of near 3%, yield strength of 800 MPa and elastic modulus of 24.5 GPa at room temperature, which can be considered as one of perfect bone replacement materials in conjunction with their excellent biocompatibility. Keywords: Ni-free shape memory alloys, Superelasticity, Porous alloys

Low-cost synthesis of silicon-doped graphene (Si-graphene) is attractive for the development of new graphene/geopolymer nanocomposites. In this work, a new insight into the properties of Si-graphene and the working mechanisms of Si-graphene in geopolymer is provided via molecular dynamics simulations. It is shown that Si-doping deteriorates the mechanical properties of graphene as Si-doping creates point defects, but it improves the surface hydrophilicity, which promotes its dispersion in aqueous media. By studying the polymerization process of Al(OH)4/Si(OH)4 monomers on Si-graphene, it is found that Si-graphene can be chemically bonded with geopolymer matrix by typical condensation reactions. Structural analysis reveals that the interfacial bonding has a beneficial effect on condensing the geopolymer composites, due to a denser interphase region. The tensile test reveals that the Young's modulus of 10% Si-graphene/geopolymer nanocomposites is twice larger than that of graphene/geopolymer nanocomposites. In addition, the interfacial bonding can strengthen the interfacial structure and arrest crack formation in geopolymer matrices.

In this paper, we report a near-α Ti alloy with tensile fracture strength and Young's modulus of 1072 MPa and 131 GPa, respectively. This alloy was compositionally designed by adding 0.4 wt% carbon to conventional Ti–6.5Al–2Sn–3Zr–1.5Mo–1.5Nb–0.4Si–0.2Y near-α Ti alloy. It has been found that the microstructure of as-cast alloy is characterized by lamellar α plates with rod-like secondary carbides along prior-β grain boundaries. After hot isostatic pressing processed, the carbides were mostly dissolved into matrix, the shape of carbides was changed from coarse and long rods to fine ellipsoid particulates. Besides, the carbon in solid solution is speculated to have the effect on the refinement of α2 phase. It is the solid solution strengthening, refinement of α2 phase and carbides and the elimination of cast defects that result in superior strength and elastic modulus to conventional Ti alloys. This work has implication to the application of Ti alloys for the aeronautics components which bear large bending moment.

TiZrNbMoxVy high-entropy alloys (HEAs) with x = 0–2, y = 1 and y = 0.3, respectively, were designed and prepared by copper mold casting technology. The phase composition and stability of these HEAs were investigated. It is shown that the HEAs with low content of V are composed of only one type of bcc solid solution phase (SSP), and demonstrate excellent phase stability at 1273 K. The high content of V and Mo results in the formation of two types of bcc SSPs and the decrease of phase stability in the HEAs. Based on the previously proposed criteria, the formation ability of solid solution phase for this kind of HEAs was comprehensively evaluated. The compressive mechanical properties of the as-cast and annealed HEAs were measured. It has been found that Mo plays a strong solid solution strengthening effect on this kind of HEAs. Especially, TiZrNbMo0.3V0.3 has the yield strength and plastic strain of 1312 MPa and >50%, respectively, and still maintains the excellent plastic deformation ability even after annealed at 1273 K for 72 h. The strengthening effect in this kind of HEAs is considered to be due to the shear modulus mismatch. The solubility limit of HEAs is correspondent to shear modulus mismatch of 29. Keywords: High-entropy alloys, TiZrNbMoV, Phase composition, Solid solution phase, Compressive properties

Pepper (Capsicum annuum L.) is a globally important and often cross-pollinated vegetable that exhibits significant heterosis. Though cytoplasmic male sterility (CMS) has an important value for pepper hybrid production, its molecular mechanism remains unclear. To explore the molecular mechanism of CMS in pepper at the proteome level, we examined the anther proteomes of a cytoplasmic male sterile line FS1030A and its maintainer line FS1030B by transmission electronic microscopy (TEM) during abortion at the microspore mother cell stage. Two dimension difference gel electrophoresis (2D-DIGE) and liquid chromatography–tandem mass spectrometry (LC–MS/MS) analyses were used to determine differentially expressed proteins. About 1070 anther protein spots were detected on each gel, and 13 protein spots were expressed differently between FS1030A and FS1030B (p

The tensile creep behavior and microstructural stability of a Co–Al–W–Ta–Ti single-crystal alloy were investigated at 1000 °C. Long-term aging at 1000 °C for 1000 h revealed stable γ–γ′ structure with 75% γ′ volume fraction. The measured positive lattice misfit resulted in directional coarsening parallel to the applied stress during creep. The γ–γ′ interfacial dislocation networks and shearing of γ′ precipitates with stacking faults and antiphase boundaries appeared to contribute to the creep resistance with 1.0% creep stain.

The accurate measurement of the spectra of elemental composition of cosmic rays is crucial to the origin of cosmic rays. The measurements of high energy cosmic rays are based on the ground experiments, and the composition reconstruction depends on the hadronic interaction model, so large uncertainties are introduced in the measurements. In this paper, we proposed a new method which is based on the characteristics of direct Cherenkov Light (DC-light) and LHAASO-WFCTA to improve resolution of reconstructed heavy nuclei spectrum. The method is independent of the interaction models for the heavy nuclei spectrum measurements.

Summary Improving vertical resolution is important for detecting more detail in seismic data. Most bandwidth-broadening methods assumed the seismic source wavelet to be time-invariant, or stationary. In practice, seismic scattering and attenuation lead to non-stationary seismic source wavelets. To address this issue, we propose to approximate the time-variant wavelet spectra using the generalized S-transform and the non-stationary polynomial fitting. We then replace the estimated time-variant wavelet spectra by bandwidth-enhanced wavelet spectra, which are made by stacking the weighted amplitude spectra of the estimated, stretched and squeezed wavelets. The stretched and squeezed wavelet spectra are calculated using the Fourier scaling theorem. We test the performance of the algorithm on synthetic and real data to obtain broader frequency spectra without greatly boosting the noise.

At present, stochastic inversion has gained increasing attention. Stochastic inversion can provide inverted results with higher resolution. Studies about multi-point geostatistics stochastic inversion are fewer because of a large amount of calculation and problems in simulating continuous variables. A stochastic inversion strategy based on multi-point geostatistics is put forward. This approach not only can effectively obtain accurate modeling facies in a few iterations because of the combination of probabilistic perturbation method, but also can quickly invert reservoir petrophysical properties such as porosity and shale content etc. through the simulated annealing algorithm and rock physics relationship. Test of model data certifies the feasibility and reliability of this strategy and inverted lithofacies and porosity with higher resolution and higher accuracy are output.

The curvelet denoising method has been successfully applied to seismic random noise attenuation. However, The conventional curvelet denoising method based on thresholding algorithm fails to preserve weak reflected signals in seismic events which have complex geometric structure. In this paper,we propose a novel curvelet denosing algorithm that applies the curvelet transform to 2D Fourier-transformed data in the fk domain instead of original data in the tx domain. In f-k domain in which the energy of the events with similar moveouts and diverse amplitude is located closely. Thus, we can take advantage of the energetic aggregation to preserve the weak reflected signals. Furthermore, an energy mean scanning algorithm based on the energetic statistical difference between effective signal and noise is proposed to perserve effective signal. The application on synthetic shot record and real imagration data demonstrates the feasibility and effectiveness of our proposed method.

To address the main stumbling-block of bulk metallic glasses (BMGs), i.e., room temperature brittleness, designing BMG matrix composites has been attracted extensive attention. Up to date, BMG composites in various alloy systems have been successfully developed by forming crystalline phases embedded in the amorphous matrix through either ex-situ or in-situ methods. In this paper, a brief review of our recent work in this topic will be presented and the novel approaches to improving composite formability and mechanical properties will also be highlighted. The main purpose of this manuscript is not to offer a comprehensive review of all the BMG composites, but instead focuses will be placed on illustrating recently developed advanced BMG composites including Fe-based BMG composite with no metalloids, Al-based BMG composite and BMG composites reinforced by the TRIP (transformation-induced plasticity) effects. The basic ideas and related mechanisms underlying the development of these novel BMG composites will be discussed.

The atomic packing and electronic structure for Co43Fe20Ta5.5B31.5 metallic glass (MG) were explored by extended X-ray absorption fine structure measurement and first-principles calculation. It is shown that the short-range order in this MG is of a (Co, Fe)B2-like, but not (Co, Fe)23B6-like, crystallographic structure. A network-like medium-range order can be formed via the build-up of B-centered Z9 〈0, 3, 6, 0〉 Voronoi polyhedra. The intrinsic strengthening mechanism is attributed to the formation of strong covalent bonding between B and Co (Fe).

The purpose of this study was to determine whether interleukin-10 (IL-10) promoter polymorphisms are associated with leprosy or their subtypes in ethnic groups from southwest China. Genotyping using TaqMan® SNP Genotyping Master Mix and ABI 7500 real-time PCR system was performed for IL-10 T3575A, G2849A, C2763A, A1082G, C819T, and C592A in 189 healthy controls (40 ± 18 years) and 193 patients (46 ± 18 years) with leprosy [multibacillary, N = 131; paucibacillary (PB), N = 62]. The allelic frequencies of -2763C (97.9 vs 94.0%, P = 0.0074) and -1082A (92.8 vs 88.6%, P = 0.0452) in leprosy patients were significantly higher than in control subjects. The genetic frequency of -2763CC and -1082AA was not only significantly higher among leprosy patients than among control subjects [odds ratio (OR) = 3.33, 95% confidence interval (95%CI) = 1.39-7.99, P = 0.0071 and OR = 1.76, 95%CI = 1.02-3.03, P = 0.0420, respectively] but also significantly higher among PB patients than among control subjects (OR = 2.46, 95%CI = 1.22-4.96, P = 0.0115 and OR = 5.58, 95%CI = 2.06-15.12, P = 0.0007, respectively). The frequency of IL-10 haplotype 3575A/2849G/2763A/1082G/819C/592C was significantly higher among leprosy patients (OR = 5.57, 95%CI = 1.13-27.52, P = 0.0351) and PB patients (OR = 10.5, 95%CI = 1.36- 81.05, P = 0.0241) than among control subjects. IL-10 promoter -2763C/CC,-1082A/AA and haplotype 3575A/2849G/2763A/1082 G/819C/592C are associated with susceptibility to leprosy and the PB subtype in southwest China.

The macrophage migration inhibitory factor (MIF) is an important proinflammatory cytokine that mediates both innate and adaptive immune responses. In this study, we identified a homolog of MIF in the Pacific white shrimp Litopenaeus vannamei. The MIF cDNA contained a 363-bp open reading frame encoding a 120-amino acid protein with a calculated molecular mass of 13.442 kDa and a theoretical isoelectric point of 6.57. The L. vannamei MIF shared high amino acid identity with MIFs of other invertebrates. Tissue distribution analysis by quantitative real-time polymerase chain reaction (qRT-PCR) revealed that the L. vannamei MIF was abundantly expressed in the blood, heart, and hepatopancreas, was moderately expressed in the gill, and was weakly expressed in the muscle and intestine. Furthermore, in order to gain a basic understanding of the role of MIF in the shrimp immune response against viral infection, its mRNA expression was determined in the hepatopancreas of L. vannamei at different stages after white spot syndrome virus (WSSV) challenge using qRT-PCR. The result indicated that the expression of MIF was significantly upregulated after WSSV injection, suggesting that MIF may be involved in the response to viral infection in shrimp.

The aim of this study is to carry out a charge-equalisation circuit for ten series-connected lithium battery cells. This circuit is composed of a class- E inverter and a multi-winding transformer, which can constantly perform the equalisation task. In addition, the zero-voltage-switching feature of the class- E inverter helps reduce the switching loss and boosts the operation efficiency of the equalisation circuit. With the application of the class- E inverter, only one active switch is present in this circuit. Since adaptation of the duty ratio is not required, the circuit control task is very simple, and can be easily realised by a low-cost pulse-width-modulation (PWM) control chip.

The oxygen ion with a dose of 10 14 (called CVDBO14) and 10 15 cm − 2 (called CVDBO15) was implanted into boron doped diamond films synthesized in chemical vapor deposition. The structural and electrical properties of different samples were characterized by XPS, Raman spectroscopy and 4-probe resistivity measurements. The results show that oxygen ion exists both in the diamond surface and the subsurface of the films. The FWHM values of CVDBO15 samples are higher than those of CVDBO14 samples, indicating that more damages existed in CVDBO15 samples. The resistivity of CVDBO15 sample series is smaller than those of CVDBO14 sample series, and the film with a larger FWHM value exhibits low resistivity. In the 1150 °C annealed sample, the activation energy decreases from 0.50 eV to 0.39 eV with the oxygen ion dose increasing from 10 14 to 10 15 cm − 2 . It is indicated that oxygen ion and the defects produced by ion implantation give contributions to the conductivity in diamond films. Some surface hydrogen is removed and pi-bonded carbon as well as C–H vibration is formed after annealing, which is also relative to the lower resistivity in the samples.

Tieguanyin Oolong tea (Camellia sinensis (L.) O. Kuntze) is a name brand important commodity for Anxi county, Fujian province in China. Four-year-old tea plants at a tea plantation in Anxi were subjected to six different irrigation treatments (i.e. 5, 10, 15, 20, and 25 d irrigation intervals for T1 to T5 with a rate of 3.5 kg water per plant, plus a non-irrigated control). After 50 d of irrigation treatments, leaf water potential was −1.70, −2.34, −2.48, −2.89, −3.55, and −4.92 MPa for treatment T1, T2, T3, T4, T5, and control, respectively. Leaf biomass yield increased by 32.8%, 21.9%, and 21.3% for T1, T2, and T3, respectively, compared to control. The net photosynthesis (Pn), stomatal conductance (gs) and transpiration (E) decreased with irrigation interval increasing. Tea polyphenol (TP) and free amino acid (AA) decreased when the irrigation intervals were increased, but caffeine (CA) content apparently increased as the irrigation intervals were increased. To balance irrigation water demand and tea yield and quality, it is recommended that the irrigation interval should be set at 10 d with a rate of 3.5 kg water per plant for the optimal production in Anxi, Fujian province of China.

This paper will discuss the design and construction of BESIII, which is designed to study physics in the tau-charm energy region utilizing the new high luminosity BEPCII double ring e+e- collider. The expected performance will be given based on Monte Carlo simulations and results of cosmic ray and beam tests. In BESIII, tracking and momentum measurements for charged particles are made by a cylindrical multilayer drift chamber in a 1 T superconducting solenoid. Charged particles are identified with a time-of-flight system based on plastic scintillators in conjunction with dE/dx (energy loss per unit pathlength) measurements in the drift chamber. Energies of electromagnetic showers are measured by a CsI(Tl) crystal calorimeter located inside the solenoid magnet. Muons are identified by arrays of resistive plate chambers in the steel magnetic flux return. The level 1 trigger system, Data Acquisition system and the event filter system based on networked computers will also be described., 57 pages, 75 figures

A rectangle crevice assembly was used to study the effects of cathodic protection (CP) potential, crevice thickness, holiday size, bubbling CO2, and surface condition on the chemical and electrochemical environment of the local solution under disbonded coatings. It is found that the cathodic protection removes dissolved oxygen from the crevice and thus shifts the solution to a more alkaline state. Furthermore, the potential of the steel reaches the protected potential range. The available protection distance increases with the negative applying potential. The steady potential and pH distribution are easily achieved, but the polarization degree is not satisfied within the thinner crevice. The difference in the solution environment is found to correlate to the holiday size. The smaller the holiday, the smaller the difference is. The presence of CO2 inhibits the formation of an alkaline environment. It is also found that the rust layer dramatically decreases the polarization rate in the crevice.

In this work, a test rig was developed to study the effect of cathodic protection (CP) on corrosion of X70 pipeline steel in the crevice area under disbonded coating through the measurements of local potential, solution pH and dissolved oxygen concentration. Results demonstrated that, in the early stage of corrosion of steel, CP cannot reach the crevice bottom to protect steel from corrosion due to the geometrical limitation. Corrosion of steel occurs preferentially inside crevice due to a separation of anodic and cathodic reaction with the depletion of dissolved oxygen in the crevice solution. The main role of CP in mitigation of sequential corrosion of steel in crevice under disbonded coating is to enhance the local solution alkalinity. With the increase of distance from the open holiday, a high cathodic polarization is required to achieve appropriate CP level at crevice bottom. A potential difference always exists between the open holiday area and inside crevice, reducing the CP effectiveness.

Hydrogen was a key factor resulting in stress corrosion cracking (SCC) of X80 pipeline steel in Ku'erle soil simulated solution. In this article, the effect of hydrogen on the SCC susceptibility of X80 steel was investigated further by slow strain rate tensile test, the surface fractures were observed using scanning electron microscopy (SEM), and the fracture mechanism of SCC was discussed. The results indicate that hydrogen increases the SCC susceptibility. The SEM micrographs of hydrogen precharged samples presents a brittle quasi-cleavage feature, and pits facilitate the transgranular crack initiation. In the electrochemical impedance spectroscopy (EIS) measurement, the decreased polarization resistance and the pitting resistance of samples with hydrogen indicate that hydrogen increases the dissolution rate and deteriorates the pitting corrosion resistance. The potentiodynamic polarization curves present that hydrogen also accelerates the dissolution rate of the crack tip.

The stress corrosion cracking susceptibility of X80 steel under applied cathodic potentials in a simulated soil solution was investigated using slow strain rate tensile tests. The fracture surfaces were observed by scanning electron microscopy. No apparent change of reduction in area was found at −775 mV in contrast to the open circuit potential. Many dimples were visible on both fracture surfaces. However, when the applied potentials were lower than −1000 mV, the SCC susceptibility increased as a result of evolution hydrogen, which diffuses into the steel. Pitts were found to be an important factor in the initiation of cracks.