摘要：In contrast to the exploration of novel photocatalytic materials,vacancy engineering of traditionalphotocatalysts comprising earth‐abundant elements represents an effective method for enhancingphotocatalytic performance without introducing alien *** minireview analyzes the latestprogress in engineering vacancies in photocatalysts,remarks on state‐of‐the‐art characterizationtechniques for vacancies,and reviews the formation chemistry and fundamental benefits of anionand cation vacancies in typical *** knowledge of these vacancies is increasing,challenges remain in this field,and possible further research is therefore also discussed.

摘要：Based on the improved particle swarm optimization(PSO) algorithm,an optimization approach for the cargo oil tank design(COTD) is presented in this *** purpose is to design an optimal overall dimension of the cargo oil tank(COT) under various kinds of constraints in the preliminary design stage.A non-linear programming model is built to simulate the optimization design,in which the requirements and rules for COTD are used as the *** the distance between the inner shell and hull,a fuzzy constraint is used to express the feasibility degree of the double-hull *** terms of the characteristic of COTD,the PSO algorithm is improved to solve this problem.A bivariate extremum strategy is presented to deal with the fuzzy constraint,by which the maximum and minimum cargo capacities are obtained ***,the simulation demonstrates the feasibility and effectiveness of the proposed approach.

摘要：Tillage practices can potentially affect soil organic carbon （SOC） accumulation in agricultural soils. A 4-year experiment was conducted to identify the influence of tillage practices on SOC sequestration in a double-cropped rice （Oryza sativa L.） field in Hunan Province of China. Three tillage treatments, no-till （NT）, conventional plow tillage （PT）, and rotary tillage （RT）, were laid in a randomized complete block design. Concentrations of SOC and bulk density （BD） of the 0-80 cm soil layer were measured, and SOC stocks of the 0-20 and 0-80 cm soil layers were calculated on an equivalent soil mass （ESM） basis and fixed depth （FD） basis. Soil carbon budget （SCB） under different tillage systems were assessed on the basis of emissions of methane （CH4） and CO2 and the amount of carbon （C） removed by the rice harvest. After four years of experiment, the NT treatment sequestrated more SOC than the other treatments. The SOC stocks in the 0-80 cm layer under NT （on an ESM basis） was as high as 129.32 Mg C ha-1, significantly higher than those under PT and RT （P 〈 0.05）. The order of SOC stocks in the 0-80 cm soil layer was NT 〉 PT 〉 RT, and the same order was observed for SCB; however, in the 0-20 cm soil layer, the RT treatment had a higher SOC stock than the PT treatment. Therefore, when comparing SOC stocks, only considering the top 20 cm of soil would lead to an incomplete evaluation for the tillage-induced effects on SOC stocks and SOC sequestrated in the subsoil layers should also be taken into consideration. The estimation of SOC stocks using the ESM instead of FD method would better reflect the actual changes in SOC stocks in the paddy filed, as the FD method amplified the tillage effects on SOC stocks. This study also indicated that NT plus straw retention on the soil surface was a viable option to increase SOC stocks in paddy soils.

摘要：Objective： To provide essential information for peptide inhibitor design, the interactions of Eps15 homology domain of Eps15 homology domain-containing protein 1 （EHD1 EH domain） with three peptides containing NPF （asparagine-proline-phenylalanine）, DPF （aspartic acid-proline-phenylalanine）, and GPF （glycine-proline-phenylalanine） motifs were deciphered at the atomic level. The binding affinities and the underlying structure basis were investigated. Methods： Molecular dynamics （MD） simulations were performed on EHD1 EH domain/peptide complexes for 60 ns using the GROMACS package. The binding free energies were calculated and decomposed by molecular mechanics/ generalized Born surface area （MM/GBSA） method using the AMBER package. The alanine scanning was performed to evaluate the binding hot spot residues using FoldX software. Results： The different binding affinities for the three peptides were affected dominantly by van der Waals interactions. Intermolecular hydrogen bonds provide the struc- tural basis of contributions of van der Waals interactions of the flanking residues to the binding. Conclusions： van der Waals interactions should be the main consideration when we design peptide inhibitors of EHD1 EH domain with high affinities. The ability to form intermolecular hydrogen bonds with protein residues can be used as the factor for choosing the flanking residues.

摘要：为了将内充种式排种器应用到花生播种机上,该文对内侧充种式排种器进行试验研究。试验基于 JPS-12 型排种器试验台,采用单因素试验和多因素多水平试验相结合的方法,分别研究排种轴转速、投种高度和种子尺寸对排种器性能的影响。性能指标选定穴距合格率、双粒率、单粒率、重播率、漏播率、破损率。对试验结果进行方差分析,确定排种盘转速在 30 r/min,投种高度在 25 cm,花生品种为丰花 5 号时,排种性能达到最优值(穴距合格率为 96.12%,双粒率为 96.36%,单粒率为 0.91%,重播率为 1.82%,漏播率为 0.91%,破损率为 0.35%)。该研究为高效花生播种机的设计提供依据。

摘要：为了研制适用于优良牧草栽培的牧草小区播种机,设计制作了牧草小区播种机排种器试验台。该试验台有一专门设计的转动机构和一个可调节的排种环。送种机构中的多个送种杯中的种子可以依次喂入排种系统,且分种锥旋转一周时,一个送种杯内的种子恰好播完。对种子在存种筒内的受力、运动过程和排种口尺寸的关系做了分析。试验台的排种正交试验表明,格盘插片的数量是影响种子分散均匀性变异系数的主要因素。当格盘数目为 12,导流槽个数为 9,并采用高丹草为试验对象时,均匀性变异系数为最小值 16.46%。该文的研究可为牧草小区播种机的研究提供参考。

摘要：针对传统根茎类作物挖掘工作铲阻力大、顺土性差、集果效果不好的问题,设计了多功能曲面挖掘铲。为提高挖掘入土性能和去土效果,挖掘铲纵向平面采用犁铧与圆弧曲面两段组合设计;为提高横向流畅顺土性能和向中集果率,挖掘铲横向平面采用功能分段及样条曲线拟合设计。通过与应用较广的普通平面多边形挖掘铲的对比试验,表明多功能曲面铲去土率提高了 4.8%,向中集果率提高了 1.2%,掉果率降低了 1.03%。但两者的挖掘阻力相差不大。该挖掘铲的设计为后续的夹持装置和去土装置的作业提供了参考。

摘要：This paper describes the characteristics of liquefied natural gas （LNG） carriers briefly. The LNG carrier includes power plant selection, vapor treatment, liquid cargo tank type, etc. Two parameters fuel substitution rate and recovery of boil of gas （BOG） volume to energy efficiency design index （EEDI） formula are added, and EEDI formula of LNG carriers is established based on ship EEDI formula. Then, based on steam turbine propulsion device of LNG carriers, mathematical models of LNG carriers＇ reference line value are established in this paper. By verification, the EEDI formula of LNG carriers described in this paper can provide a reference for LNG carrier EEDI calculation and green shipbuilding.

摘要：免耕播种机是在地表有残茬和秸秆条件下直接播种,因此保持其破茬质量与播种深度稳定性尤为重要。近年来许多厂家以加大整机重量的方法来提高播深稳定性,这种方法增加了机械对土壤的压实,垄形被压平,沟底坚实度增大,并且机械耗油量增加,影响了作物产量和经济效益。该文以2BG-2型玉米垄作免耕播种机为对象,研究了整机设计与单体受力模型,建立了播种深度变化的数学模型,据此模型进行了计算机模拟,研究了影响播种机播种深度稳定性的相关因素。分析表明:在保持必要的机器质量条件下,应合理布置各部件以加大转动惯量并适当增大压力弹簧的刚度系数以保持播种深度稳定。在不同的机器质量和弹簧刚度系数下,理论摆角和实测摆角随时间的变化趋势基本相同;系统质量为70、110和150 kg时,理论摆角与实测摆角的平均相对误差分别为7.86%、6.98%和8.07%,理论曲线与实测曲线的决定系数分别为0.9707,0.9692和0.9697;刚度系数为16、20和25 N/mm时,理论摆角与实测摆角的平均相对误差分别为7.45%、7.91%和8.73%,理论曲线与实测曲线的决定系数分别为0.9767,0.9720和0.9603;建立的播种深度模型可以反映播种作业时摆角的变化趋势。该文可为东北垄作区免耕播种机的设计提供参考。

摘要：为了研究输送带速度和光谱仪安装高度对近红外在线检测秸秆-煤混燃物的影响。该研究收集并制备秸秆样品80个、煤样品9个,制备秸秆质量分数为70%～99%的秸秆-煤混燃物样品120个(质量分数增量为1%)、秸秆质量分数为1%～30%的秸秆-煤混燃物样品120个(质量分数增量为1%)。在输送带速度分别为300、600、1 000和1 400 mm/s,光谱仪安装高度分别为50、56、59和65 mm的条件下,使用Thermo Fisher scientific Antaris Target FT-NIR型光谱仪获取样品近红外光谱。使用线性判别分析法建立定性分析模型,使用偏最小二乘法建立定量分析模型。结果表明,光谱仪安装高度建议为50～65 mm,输送带速度建议小于300 mm/s。该研究可为近红外光谱法在线定性和定量检测生物质-煤混燃物的方法学研究和相关仪器设计提供参考。