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[Objective] The aim of this study is to investigate the effects of different residue amounts on nitrogen utilization efficiency and losses. [Methods] The experiment involved five different residue amounts (0, 180, 360, 720, 1 440 kg/hm2) and two types of residues (polyethylene and biodegradable residues). Through pot experiments, the study examined the impact of different residue contents on soil total nitrogen, nitrogen gas losses, nitrogen fertilizer utilization efficiency, and tomato growth indicators. [Results] The research indicates that with an increase in residue content, the cumulative emissions of ammonia and nitrous oxide in the soil show a trend of first increasing and then decreasing. When the residue content reaches 720 kg/hm2, the cumulative ammonia emission significantly decreases by 11.31% to 13.70%, and nitrous oxide emission decreases by 4.74% to 5.13%. There was no significant difference in nitrogen residue in the soil. When the residue content is below 180 kg/hm2, the residue promotes tomato growth; when the residue content is above 180 kg/hm2, it inhibits tomato growth. Low residue content has no significant effect on nitrogen fertilizer utilization efficiency. However, when the content is higher than 360 kg/hm2, nitrogen fertilizer utilization efficiency shows a negative correlation with residue content. Through comprehensive analysis, it is suggested that soil residue content should be controlled within 180 kg/hm2 to avoid negative effects on crop growth. Furthermore, due to the degradable nature of biodegradable residues, their adverse effects on nitrogen absorption by plants and nitrogen fertilizer utilization efficiency are weaker than those of polyethylene residues. [Conclusion] Therefore, replacing polyethylene residues with biodegradable residues is considered feasible.

Based on the test site at the Qinghai�Tibet Plateau with an altitude of 4 300 m, atmospheric neutron single event effects of a 65 nm high�speed large�area static random access memory (SRAM) array were measured in real�time. By breaking through key technologies such as effect screening, intelligent remote measurement and control, a total of 39 single�event upset were observed during the 153 d test period, of which multiple�cell upset (MCU) accounts for 23%, and the largest MCU is 9 bits. The contribution ratios of high�energy neutron, thermal neutron and alpha particle were analyzed in detail, and based on the multi�ground neutron flux data, the single�bit upset (SBU) and MCU failure in time (FIT) at Beijing ground and 10 km high�altitude application were deduced. It is found that the main cause of soft error on the ground is the alpha particle. As the altitude increases, the contribution of atmospheric neutron to soft error increases significantly. All MCUs are caused by high�energy neutron, and the MCU FIT value at an altitude of 10 km in Beijing is obviously increased. Its proportion increases from 8% of the ground to 26%. In combination with the device layout, an in�depth analysis of the MCU generation mechanism was carried out. Finally, a goal�oriented optimization method of memory soft error hardening strategy was proposed.

Teacher-led classical instruction lacks interactions feedbacks and thus leads to a low learning efficiency. Serving as advanced educational concept and method, outcome-based education (OBE) and BOPPPS mode gradually become the leading concept in the remodeling of basic medical education. In order to improve the quality of microbial genetics teaching, this article aims to summarize the methods and experience of applying BOPPPS mode to microbial genetics directed by OBE, which hopefully stimulates medical students' interests of initiative learning and active exploration, cultivates students' ability of raising and resolving questions, develops the awareness of cooperative learning, and finally achieves the goal of improved classroom learning.

The welding materials and processes of fusion welding joint for TA1-X80 explosive composite plate were designed by corresponding welding experiment. Based on the microstructure, composition and properties of the welded joints, a good welding material and process as transition layer for welding titanium-steel composite plate was obtained. The results show that Y-type groove and double-layer transition for metallurgical connection of titanium-steel composite plate are effective. The double-layer consists of nearly titanium layer of Ti-Ni-Al alloy and nearly steel layer of Ni-Cr-Fe alloy. The weld microstructure is changed from coarse equiaxed grain in the titanium layer to fine equiaxed grain or dendrite in the transition layer, and finally is interlaced with the structure of steel. The tensile and yield strength of the welded joint are 501.1MPa and 373.0MPa respectively, which reach the equal match. But the plasticity and toughness are slightly insufficient, which can be improved subsequently by reducing the thickness of the transition layer and adjusting the elements for refining grain size.

24 cycles Ti-TiN-Zr-ZrN soft-hard alternating multilayer film was deposited on TC11 titanium alloy by vacuum cathodic arc deposition method. The structure and performance of the multilayer film, especially wear and sand erosion resistance were investigated by various analytical methods including pin on disc wear tester, sand erosion tester, 3D surface topography instrument, scanning electron microscopy (SEM), X-ray diffraction(XRD), micro-hardness tester and scratch adhesion tester. The results indicate that the Vickers-hardness of the multilayer film with thickness of 5.8μm can reach up to 28.10GPa. The adhesive strength of these coatings can be as high as 56N. Wear rate of the multilayer coated alloy is one order of magnitude smaller than bare one, which decreased from 7.06×10-13 m3·N-1·m-1 to 3.03×10-14m3·N-1·m-1. Multilayer films can play the role in hindering the extension of cracks, and thus sand erosion properties of the TC11 titanium alloy substrates are improved.

The parameters of Laser Raman Spectra can reflect the maturity of organic matter, but there are few related studies on the organic matter in high-and overhigh-maturity of shale and coal. The maturity of shale from Southern China and anthracite from the Qinshui and Bide-Santang Basin have been determined by Laser Raman Spectroscopy, rock eval pyrolysis and vitrinite reflectance for maturity analysis and are reported in this paper. The reflectance equation proposed previously, was applied and the reflectance gained by Raman (RmcRo) was calculated. The correlation fitted regressed with the pyrolysis peak temperature (Tmax) and measured vitrinite reflectance (Ro). The results show that the wedge-shaped bands/peaks, first order bands/peaks (D and G) and second order bands/peaks (S2, S3 and S4) of shale and anthracite spectra are clear. The Raman reflectance (RmcRo) shows good correlations with pyrolysis peak temperature (Tmax, R2=0.9173) and vitrinite reflectance (Ro, R2=0.9614). The Raman reflectance (RmcRo) shows consistency and reliability with Tmax and Ro in the maturity evaluation. The multi-point test of Raman can reveal the heterogeneous variation of shale during diagenesis and has more accuracy and higher reliability in heterogeneity reflecting than the previously carried-out single-point test. The shale has a larger variation coefficient of RmcRo than that of coal and shows stronger organic matter heterogeneity. The organic matter of shale shows heterogeneous variation during diagenesis, causing a larger variation coefficient of RmcRo than that of coal and stronger organic matter heterogeneity than those of coal. The research results provide a basis for the evaluation of the organic matter maturity of the high-over mature shale and coal.

Based on latest drilling data, outcrop geologic survey around the area and laboratory test results of lots of rock samples, analysed shale gas generation conditions and potential of Silurian Longmaxi shale in south of Sichuan Basin with the regional distribution, organic geochemical and reservoir characteristics, gas concentration and reservoir pressure of organic-rich shale rock. Through integrated study, it is thought that: Silurian Longmaxi Formation in the study area features high organic content (TOC:0.35% ~ 18.40% , average of 2.52% ) , high net shale thickness(20 260 m) ,high brittle mineral content (more than 40% -70% ) , lots of nanoporosity in organic and high gas content (0.3 ~ 5.1 m³/t,average of 1.9 m³/t), Moderate burial depth (2 000 ~ 3 600 m) is favour of the generation and accumulation of shale gas. Silurian Longmaxi Formation is one of the favorable stratas of shale gas exploration and development in China ,that accessed frequently gas show in drilling processes and obtained industrialization breakthrough; areas of Weiyuan, Longchang-Yongchuan and Changning-Gongxian are three realistic and favorable targets for Silurian Longmaxi shale gas exploration and development. [ABSTRACT FROM AUTHOR]

The most suitable background electrolytes (BGEs) for simultaneous separation of 15 nucleosides by different modes of capillary electrophoresis (CE) were obtained. Various modes of CE were performed including capillary zone electrophoresis (CZE), capillary electrophoresis-electrospray ionization-time of flight mass spectrometry (CE-ESI-TOF/MS) and micellar electrokinetic chromatography (MEKC). The electrolyte buffers using sodium tetraborate decahydrate, disodium hydrogen phosphate, sodium acetate, sodium bicarbonate, ammonium acetate or 1, 2-diamino-ethane (DEA) were tested, and the best of them were systematically optimized. In CZE mode, the nucleosides could not be separated completely with sodium tetraborate decahydrate or disodium hydrogen phosphate as BGEs, demonstrating the limited applicability of the two buffer systems for complex samples. However, with 300 mmol/L DEA (containing 2% acetone) as BGE, 15 nucleosides could be separated with good resolution and peak shape, which proved that the DEA buffer was most suitable in CZE. The best buffer system in MEKC mode was 25 mmol/L disodium hydrogen phosphate with 70 mmol/L sodium dodecyl sulfate (SDS), and it was successfully applied for the separation of the nucleosides in Chinese Anthopleura lanthogrammica Berkly. The optimum buffer system for CE-ESI-TOF/MS analysis was 20 mmol/L ammonium acetate (pH 10.0). In the positive ion mode, the MS signals of each compound were better than those in the literature using DEA as BGE. The results of this study demonstrated the applicability of different buffer systems for the simultaneous separation of 15 nucleosides, and were helpful for the development of CE method in complex sample separation.

A method for the simultaneous determination of 7 nucleosides in Asterias rollestoni was developed using reversed-phase high performance liquid chromatography (RP-HPLC). Analytes were extracted by ultrasonic-assisted extraction and separated on two different C18 columns, which were connected in series, under the gradient elution with the mobile phases of methanol and 0.2% (v/v) acetic acid/water at room temperature. The chromatographic conditions were as follows: flow rate, 0.8 mL/min; detection wavelength, 260 nm; injection volume, 20 microL. Under the optimized conditions, good linear relationships between the values of mass concentrations and the peak areas of hypoxanthine, uridine, xanthine, thymine, inosine, guanosine and thymidine were observed in the ranges of 0.65 -40, 0.80 -40, 0.80 -40, 1.15 - 40, 0.80 - 40, 0.50 - 40, and 0.65 - 40 mg/L, respectively. The relative standard deviations were around 0.72% - 3.23% and the recoveries were around 90.00% - 105.00%. The results showed that the developed method is sensitive, accurate and reproducible. It is suitable for the analysis of nucleosides in Asterias rollestoni with high recoveries and it is expected to be used for the quality control and evaluation of Asterias rollestoni.

Objective: To investigate the configuration of colic vessels in Chinese and its influence on the operation of esophageal replacement with colon (ERC)., Methods: The origin, trend, branching, configuration, and distribution of the colic vessels, the intensity of the colic arterial impulse, the integrity of the marginal artery at the splenic flexure and hepatic flexure of colon were observed during the operation of ERC among 582 patients undergoing ERC, 402 males mad 180 females, aged 2 approximately 74, from 22 provinces, municipality, and autonomous regions., Results: The left colic artery (LCA) stemmed from the inferior mesenteric artery (IMA) in 97.3% of the patients, with an absence rate of 0.7%. The middle colic artery (MCA) stemmed from the superior mesenteric artery (SMA) in 77.8% of the patients with an absence rate of 8.2%. Accessory middle colic artery (acMCA), originating from the right colic artery, could be seen in 6.2% of the patients 39.7% of the right colic artery (RCA) stemmed from the SMA by itself, 23.0% of the RMA stemmed together with MCA, and 28.0% of the RCA stemmed together with the ileocolic artery. The absence rate of RCA was 9.8%. The intactness rate of marginal artery was 96.8% at the splenic flexure of colon, and was 88.7% at the hepatic flexure. The Rolan arch was seen in only 7.6% of the patients., Conclusion: The configuration of colic vessels in Chinese was basically similar to those of the results of autopsies carried out abroad. The optimal supply artery of colic segment during ERC is LCA, followed by LCA. Attention should be paid to the integrity of marginal arteries and veins in the patients with history of epigastric operation.