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The international thermonuclear experimental reactor (ITER) project aims to build a tokamak fusion test reactor to verify the feasibility of fusion reactors. The test blanket module (TBM) is the key component of the international thermonuclear experimental reactor. The fusion design study team proposed the concept of the dual-functional lithium-lead test blanket module (DFLL-TBM). The integral severe accident analysis (ISAA) is a self-developed ISAA code that models the progression of severe accidents in nuclear power plants. A broad spectrum of severe accident phenomena including fission product release and transport behavior is modeled in ISAA. In this paper, a new version of ISAA, referred to as ISAA-DFLL is introduced for the application of DFLL-TBM test blanket module into the treatment of multi fluids and the modules of the new physical property and heat transfer. The modification is verified by comparing the steady-state temperature distribution of the DFLL-TBM first wall with the design parameters. Then accident analysis of In-vessel loss of helium coolant in first wall and TBM pipe is conducted by using the ISAA-DFLL code. By comparing the calculation results with the general safety requirements for TBM, it is concluded that the design of the DFLL-TBM system and the modifications of the current version are reasonable and accurate.

Using 325 mesh flake graphite as raw material, graphite oxide (GO) was synthesized by improved Hummers method. Nitrogen-doped reduced graphene oxide (N-rGO) carrier was prepared by hydrothermal method using urea as nitrogen source, and then supported Ni/N-rGO catalyst was prepared by impregnation method. The prepared catalysts were characterized and analyzed by N2 adsorption-desorption, XRD, SEM, H2-TPR and other methods. The hydrogenation performance of Ni catalysts supported by N-rGO, reduced graphene oxide (rGO) and activated carbon (AC) were compared under the reaction conditions of 150°C, 0.4 MPa and 2.0 h with selective hydrogenation of phenol to cyclohexanone as probe reaction. The results show that the N-rGO support not only has a large specific surface area and suitable pore structure, but also has good synergistic effect with nickel metal, and the Ni/N-rGO catalyst thus shows excellent catalytic activity and selectivity.

A simple, metal-free protocol for unsymmetrical biaryl coupling using H5IO6 is reported. H5IO6 was evaluated for a novel application in the oxidative cross-coupling of phenol-arene, phenol-phenol, and phenol-naphthol compounds. In this work, most of the couplings were completed within 30 min at ambient temperature. 30 coupling products were conveniently obtained using only 0.5 equivalent of H5IO6 in HFIP. A mechanism by which the transformation occurs is proposed.

It is very important to understand water ecology and the carbon cycle process by studying the composition, source, spectral characteristics, and influence factors of chromophoric dissolved organic matter (CDOM). The optical characteristics, composition, and source of CDOM in 71 water samples were collected from the lakes and four rivers of the Taibaishan Nature Reserve in the summer of 2019. The rivers included the Bawang, Heihe, Shitou, and Xushui Rivers. They were analyzed by UV-Vis spectral and three-dimensional fluorescence spectroscopy, combined with a parallel factor analysis model and redundant analysis. The results showed that CDOM in the water of the Taibaishan Nature Reserve contained two types of four fluorescent components, in which the humus-like components C1 and C2 were the main components of CDOM. The relative contribution of C1 and C2 to the rivers was 82%-96%, which was significantly larger than the lakes. All fluorescence indexes (FI) were larger than 1.8, the index of recent autochthonous contribution (BIX), and the index of freshness (

Different meter-class, thousand-turn, self-integrating Rogowski coils for the TPG-series generators are designed. The features of this type of coils are the extremely large turn number (several thousands) and the 50-Ω characteristic impedance of the cable used as the current viewing resistor. After calibrations for these large-size coils, it is found that the experimental sensitivities are larger than the theoretical ones and that the deviations range from 4% to 20%, which cannot be accepted. The deviations are analysed in perspective of coil size and cable length. It is concluded that the sensitivity deviations are mainly due to the increased coil size and partly due to the long cables. A modified theoretical sensitivity expression of the large-size, self-integrating Rogowski coils is presented based on the transmission-line model, which embodies the factors of coil size and cable length. A method to test the key parameter in the model, the characteristic impedance of the coil, Z, is also presented. With this expression and the method, the theoretical sensitivities for the TPG-series generators are re-calculated, which agree well with the experimental ones, only with a deviation around 2%. It is suggested that the modified theoretical sensitivity expression can be used to calculate the sensitivity of the self-integrating Rogowski Coils with a large size.

To evaluate and analyze the accuracy of three-dimensional camera system acquisition based on stereophotography for the photographic acquisition of images of facial deformities.3D digital models of 45 waxen facial models of patients with facial deformities were obtained via a 3D camera system based on stereophotography. A total of 19 feature lines were measured on each 3D model by using the software. The measurements taken by the coordinate-measuring machine were accepted as standard values. Statistical analysis was performed to evaluate the accuracy of the system and the corresponding factors.Statistical analysis results showed that the measured values of the characteristic distance obtained by 3D camera system were statistically different from the standard values (P0.001). Convex deformities had significant influence on the measuring error of 3D camera system (P0.05), while cleft deformities had no significant influence on the measuring error (P0.05). The facial regions significantly influenced measuring error (P0.05). The deformities had no significant influence on the percentage of measurement values (P0.05). The middle facial regions had significant difference with bilateral facial regions on the percentage of measurement values (P0.05), while the left and right facial regions had no significant difference (P0.05).The accuracy of 3D camera system based on stereophotography for the photographic acquisition of facial deformities are influenced by the morphology of the facial deformities and facial regions. Moreover, the measuring error is acceptable in clinical settings.目的 探究基于立体摄影技术的三维照相系统获取畸形面部影像的精确性及其影响因素。方法 采用基于立体摄影技术的三维照相系统采集45个面部畸形的蜡制脸模的表面数据，测量19个面部软组织特征线距，以三坐标仪采集测量结果作为标准值，分析三维照相系统获取畸形面部影像的精确性，以及不同畸形形态与面部区域对测量结果精确性的影响。结果 三维照相系统获取的特征线距的测量值与标准值具有统计学差异（P0.001）。凸起畸形对三维照相系统的测量误差有显著性影响（P0.05），裂隙畸形对三维照相系统的测量误差无显著性影响（P0.05）。不同面部区域的三维照相系统测量误差有统计学差异（P0.05）。畸形形态对三维照相系统测量偏大百分比无显著性影响（P0.05）。中间区域与面部两侧区域的测量偏大百分比具有统计学差异（P0.05），左侧区域与右侧区域的测量偏大百分比无统计学差异（P0.05）。结论 对畸形面部影像的分析，基于立体摄影技术的三维照相系统测量正畸临床常规线性项目的精确性受畸形形态与面部区域的影响，但误差在临床可接受范围内。.

The first total synthesis of a major component of marine glycolipid vesparioside B ( Scheme 1 , 1, R1 = n-C22H45, R2 = n-C14H29) has been accomplished through a convergent [4 + 3] coupling strategy. Key steps included stereoselective installment of a set of challenging 1,2-cis-glycoside bonds. A 2-quinolinecarbonyl-assisted α-galactosylation and a novel β-arabinosylation were developed, respectively, to synthesize the α-galactofuranosidic and the β-arabinopyranosidic linkages. Furthermore, a 4,6-O-benzylidene-controlled α-galactopyranosylation reaction allowed the efficient connection of the left tetrasaccharide donor 2 with the right disaccharide lipid acceptor 3, hence leading to the total synthesis of 1.

For composite electromagnetic (EM) scattering from rough surface and target above it in near-field condition, modified shooting and bouncing ray (SBR) method and integral equation method (IEM), which are analytic methods combined with two-scale model for rough surface, are proposed to solve the composite near-field scattering problems. And the modified method is verified in effectiveness and accuracy by comparing the simulation results with measured results. Finally, the composite near-fielding scattering characteristics of a slanted plane and rough water surface below are obtained by using the proposed methods, and the dynamic tendency of composite scattering characteristics versus near-fielding distance is analyzed, which may have practical contribution to engineering programs in need of radar targets near-field characteristics under extra-low-altitude conditions.

In the methods of Near-Field ISAR imaging based Near-Field Far-Field Transformation (NFFFT), all target scattering is assumed to occur at the location of the incident field excitation. It's obviously non-localized scattering phenomenon such as re-entrant cavity scattering and surface traveling waves cannot be effectively handled. The presented method could find out where the non-localized scattering phenomenon occurred and separate from the scattering signatures. Then we can emendate the non-localized scattering part and improve the NFFFT precision. We present a method for recognition and extraction of scattering mechanisms. Firstly, calculate the spectrogram of target's scattering echo by an adaptive time-frequency transformation method named Adaptive Gaussian Representation (AGR). Then separate the wide components and narrow components of the Gaussian functions from the echo. Making images by the two parts respectively, the local and non-local scattering mechanisms and where it happened can be recognized. Beside of the NFFFT using, the method we presented could also be used to recognize and extract scattering mechanisms in complex target, and can be used in stealth design, SAR/ISAR image processing, etc.

In a 3-year field experiment, effects of reducing N fertilizer, straw returning and dicyandiamide (DCD) application on wheat yield and nitrogen budgets under wheat-fallow system were studied in rain-fed region. The experiment was carried out in Yangling of Shaanxi Province, and 4 treatments were installed including no nitrogen (CK), 220 kg N·hm通过在陕西杨凌进行的3年田间试验研究了减氮+秸秆还田以及添加双氰胺(DCD)对旱地雨养区冬小麦-夏休闲种植模式小麦产量和氮平衡的影响.试验共设置不施氮肥(CK)、施氮220 kg·hm

Over-application and inefficient use of nitrogen (N) fertilizer is a serious issue throughout China, with adverse environmental and economic impacts. In this paper we present evidence of this in the wheat/maize double cropping system in the Guanzhong Plain in Shaanxi Province, northwest China. Results show the economic benefits of overcoming this problem are greatest for the lowest income farmers. We also outline new advisory approaches that could aid delivery of information to farmers. Evidence of excessive N fertilizer applications, and opportunities to maintain or even increase crop yields with lower rates of N, are presented from several sources. A survey of N applications to maize by 80–100 farmers showed that 77% were applying N at rates in excess of those recommended by the local advisory agencies. Experiments with maize and wheat at 120 sites, testing a range of N application rates, show remarkably small yield responses to applied N and high yields even when no N is applied. This is mainly because of large nitrate residues accumulated in the soil from past N fertilizer applications. Trials were conducted in 30 farmers’ fields comparing the farmer’s usual N rate with a lower rate based on a combination of local recommendations and measurements of nitrate in soil. On average, N rates to maize and wheat could be decreased by 70% and 20%, respectively, with no loss of yield and sometimes small increases. Economic assessments and household surveys showed the economic benefits for farmers of moving to more rational use of N fertilizer. Even a 30% reduction in N use would increase household income by 2–9%, and a 50% reduction by 4–15%. In all cases the poorest farmers benefit the most because fertilizer represents a larger percentage of their expenditure, so policies and practices leading to more rational N use are clearly pro-poor. Advisory approaches based on an N budget approach are outlined as an alternative to traditional approaches where farmers are simply given a recommended application rate. Simple in-field measurements of nitrate concentration in soil, using commercially available nitrate-sensitive strips giving a color reaction, may be a useful supplement for field-specific advisory work if the logistics at village level can be organised.

An efficient methodology for the synthesis of α-Kdo glycosidic bonds has been developed with 5,7-O-di-tert-butylsilylene (DTBS) protected Kdo ethyl thioglycosides as glycosyl donors. The approach permits a wide scope of acceptors to be used, thus affording biologically significant Kdo glycosides in good to excellent chemical yields with complete α-selectivity. The synthetic utility of an orthogonally protected Kdo donor has been demonstrated by concise preparation of two α-Kdo-containing oligosaccharides.

β-Thiolactones have enabled the sterically demanding peptidyl ligations of Val–Leu, Val–Val and Val–Pro using a one-pot NCL and desulfurization protocol., The ligation of sterically demanding peptidyl sites such as those involving Val–Val and Val–Pro linkages has proven to be extremely challenging with conventional NCL methods that rely on exogenous thiol additives. Herein, we report an efficient β-thiolactone-mediated additive-free NCL protocol that enables the establishment of these connections in good yield. The rapid NCL was followed by in situ desulfurization. Reaction rates between β-thiolactones and conventional thioesters towards NCL were also investigated, and direct aminolysis was ruled out as a possible pathway. Finally, the potent cytotoxic cyclic-peptide axinastatin 1 has been prepared using the developed methodology.

Biomass energy is considered to be an ideal renewable alternative energy and herbaceous energy plants as an important biomass resources became research hot spot all over the world. Switchgrass (Panicum virgatum L.) is international recognized as the most suitable bioenergy plant for the past few years. In order to obtain the basic data about seed germination characteristics on switchgrass as a bioenergy grass, different temperatures are investigated to select reliability indexes on seed germination of two species switchgrass from eight measurement indexes and then analyzed main factors influencing seed vigor by a principal component analysis. The result showed that co-efficiency of germination (CG), germination index (GI) and Peak value (PV) from eight germination indexes can be used as measurement indexes for detect seed germination of two species switchgrass.

This paper proposes an e-cient parallel shooting and bouncing ray (SBR) method on the graphics processing unit (GPU) cluster for solving the electromagnetic scattering problems. At each incident direction, the parallel SBR method partitions the virtual aperture into sub-apertures, and distributes the computational process of each sub-aperture over GPU nodes. As ray tubes in the virtual aperture do not have the same computational time, the parallel e-ciency highly depends on how to partition the virtual aperture. This paper addresses this issue by a dynamic partitioning scheme according to the computational time at the previous angle, which can achieve excellent load balance. Numerical examples are presented to demonstrate the accuracy, high parallel e-ciency, good scalability and versatility of the proposed method.

In view of the near sea area, the formulae finite depth spectrum is given in the paper, the spectral model under different water depths is obtained, by using Kirchhoff approximation and the modified two-scale method, the scattering coefficient and the Doppler echo signal of near sea area are calculated, the agreement with measured data proved the correctness and validity of the near sea area scattering model.

In this paper, the shooting and bouncing ray (SBR) method in combination with the truncated wedge incremental length difiraction coe-cients (TW-ILDCs) is implemented on the heterogeneous CPU-GPU architecture to efiectively solve the electromagnetic scattering problems. The SBR is mapped to the GPU because numerous independent ray tubes can make full use of the massively parallel resources on the GPU, while the TW- ILDCs are implemented on the CPU since they require complex and high-precision numerical calculation to get the accurate result. As the computation times of neighboring aspect angles are similar, a dynamic load adjustment method is presented to achieve reasonable load balancing between the CPU and GPU. Applications, including the radar cross section (RCS) prediction and inverse synthetic aperture radar (ISAR) imaging, demonstrate that the proposed method can greatly improve the computational e-ciency by fully utilizing all available resources of the heterogeneous system.

This paper presents a GPU-based multiresolution shooting and bouncing ray (MSBR) method with the kd-tree acceleration structure for the fast radar cross section (RCS) prediction of electrically large and complex targets. The multiresolution grid algorithm can greatly reduce the total number of ray tubes, as it adaptively adjusts the density of ray tubes for regions with difierent complexities of their structures, while the kd-tree acceleration structure can highly decrease the number of ray-patch intersection tests. The multiresolution grid technique and kd-tree traversal algorithm are fully implemented on the GPU to further accelerate the SBR by exploiting the massively parallel computing ability. Numerical experiments demonstrate that the proposed GPU-based MSBR can signiflcantly improve the computational e-ciency. It is about 40 times faster than the CPU MSBR, and at least 4.8 times faster than the GPU-based SBR without the multiresolution grid algorithm.

Based on the antenna radiation theory, the universality, detectability and main characteristics of linear non-uniform electromagnetic wave are analyzed. When an object is illuminated by a linear non-uniform electromagnetic wave, there exists special phenomenon, such as induced eddy current and so on. Meanwhile, the definition of scattering function illuminated by a linear non-uniform electromagnetic wave is given. Computed by the method of moment (MoM), it is shown that the scattering characteristic of a metallic plate illuminated by a non-uniform wave is totally different from that by a uniform plane wave, and the peak magnitude is even bigger, which sufficiently demonstrates the significance of linear non-uniform electromagnetic wave in material detection.

The shooting and bouncing ray (SBR) method is effectively implemented on the graphics processing unit (GPU) for scattering problems of electrically large complex target and randomly rough surface composite model. Results obtained using the proposed approach are compared against results generated by commercial software and those obtained with the CPU-based SBR. The good agreement and significant acceleration show that the newly developed method is capable of modeling the composite scattering from complex and electrically large targets over a randomly rough surface.

This paper introduced the principles and applications of macroinvertebrate community index (MCI) and quantitative macroinvertebrate community index (QMCI) commonly used in New Zealand, and applied them to monitor and assess 53 sites in 40 rivers in Wellington region of the Country. Both MCI and QMCI were correlated with the rivers nutrients enrichment significantly, suggesting that it was possible to use the two indices to monitor and assess the nutrient pollution of water body. The MCI and QMCI could rapidly and easily assess water body quality, and the assessment showed that in Wellington region, the rivers water quality was overall good, but some of the rivers were poor in water quality. There was a significant correlation between MCI and QMCI, but, as compared with QMCI, MCI was better correlated with the rivers nutrients enrichment, and thus, recommended to be applied to assess water body quality. The aim of this paper was to introduce the related researchers in China how to use MCI and QMCI in monitoring and assessing water body quality, and gave some ideas on improving the development of biotic index with macroinvertebrates in rivers water quality assessment in China.

The purpose of this study was to obtain immunogenic proteins and potential proteins of interest that were isolated from Mycoplasma capricolum subsp. capripneumoniae (Mccp) by MALDI-TOF mass spectrometry. One-dimensional SDS-PAGE and two-dimensional gel electrophoresis of whole cell preparation were conducted, and membrane proteome maps were prepared by immunoblotting. One-dimensional SDS-PAGE identified three immunogenic proteins with molecular masses in the range 29-97.2 kDa, two of which were in the membrane protein fraction. After two-dimensional gel electrophoresis, 20 highly immunogenic proteins were identified in the whole cell protein preparation while 9 immunogenic proteins were identified in the membrane protein fraction. This indicated that membrane proteins were the principle immunogenic proteins in Mccp. These proteins may have potential for the development of improved diagnostic tests and possible vaccines.

Haemophilus parasuis is known to produce a group of virulence-associated autotransporter (AT) proteins, VtaAs; however, no other ATs have been characterized yet. On the basis of the reported sequence of a putative espP2 gene for extracellular serine protease (ESP)-like protein of H. parasuis, this putative AT gene was successfully amplified from H. parasuis serotype 5 field strain HPS0819, cloned and sequenced. The confirmed ORF sequence showed 100% identity with the reported putative espP2 gene. The recombinant ESP-like protein purified from Escherichia coli with a pET expression system was used for immunological characterization. An approximately 85 kDa antigen was detected in cultured H. parasuis by using antiserum to the purified ESP-like protein, and antibodies against the recombinant ESP-like protein were detected in a selected serum from pigs with experimental H. parasuis infection. The results indicated that H. parasuis could produce ESP-like protein in vitro and in vivo. In an immune protection study using guinea pigs, 6 out of 10 animals immunized with the recombinant ESP-like protein survived after challenge with 5 × 10(9) bacteria of strain HPS0819, whereas 7 out of 10 animals immunized with formalin-inactivated H0819 bacterin survived after challenge. The results suggest that ESP-like protein could be one of the vaccine antigen candidates for H. parasuis infection.

By using in situ leaching device, a field experiment was conducted to study the effects of nitrogen fertilization rate and straw mulching on the nitrate leaching at 90 cm soil depth, nitrate accumulation in soil profile (0-100 cm), crop yield, and nitrogen balance of wheat-corn rotation farmland in Guanzhong area of Shaanxi. Six treatments were installed, i. e., no fertilization (N1, 0 kg x hm(-2) x a(-1)), conventional fertilization (N2, 471 kg x hm(-2) x a(-1)), recommended fertilization (N3, 330 kg x hm(-2) x a(-1)), reduced N application (N4, 165 kg x hm(-2) x a(-1)), increased N application (N5, 495 kg x hm(-2) x a(-1)), and recommended fertilization plus straw mulching (N3 + S). The nitrate leaching loss was increased with increasing N fertilization rate. Excessive N fertilization and straw mulching could easily cause nitrate leaching. In treatment N3 + S, the annual NO3(-) -N loss at 90 cm soil depth was the greatest (22.32 kg N x hm(-2)), and the NO3(-) -N loss from N fertilization was 16.44 kg N x hm(-2) x a(-1), being 158.9% higher than that in treatment N3. Nitrate mainly accumulated in 20-60 cm soil layer. When the N application rate was 330 kg N x hm(-2) x a(-1), straw mulching had less effect on the NO3(-) -N distribution in soil profile. No significant difference was observed in the crop yield among the treatments, but reduced N application (N4) tended to decrease the yield. Under our experimental condition, a fertilization rate of 150 kg N x hm(-2) x a(-1) for wheat and 180 kg N x hm(-2) x a(-1) for maize could ensure the crop production and reduce the soil nitrate leaching and accumulation.

A powerful and cost effective home security system based on GSM communication network and wireless communication module CC1100 is proposed for anti-theft, fireproofing, waterproofing, anti-gas leak and remote appliance control. The system uses STC89C516 microcontroller as the core and real-timely detects the home environment through a variety of sensors. The dual detections are utilized to reduce the false alarm rate and enhance system reliability and interference immunity. The wireless data transmission is adopted between the main controller and sensor nodes, which does not require a lot of wiring. The bidirection communication between the main controller and the mobile terminal is realized by the GSM networks. Once detecting suspicious activities, the system sends an alarm message to the host’s mobile phone. The user can remotely query the home security status and control the home appliance by the GSM module. The communication is assured within the GSM coverage area, and the distance is unlimited. The GSM short message alarm overcomes the hidden troubles of vulnerable damage and no alarm when calling in the fixed telephone dialing. The interaction interface is optimized. The user can modify the passwords, change the target phone number, alter the upper and lower limits of alarm, query the alarm recording and deploy/cancel defense via the LCD and keyboard. The buttons are installed for help in case of emergencies. The test results show that the system can real-timely monitor and remotely query the home environment, control the appliances and initiatively send alarm messages in case of accidents. The system possesses full function, high reliability, low false alarm rate, strong expansion, friendly user interface and low cost. The application space is very broad.

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