含火药浆状炸药水分流动及控制

针对火药表面水分分布的特点,通过了原子力显微镜分析了单基药和双芳-3表面的差异性,通过两种温度恒温条件30℃及100℃对含水单基药和双芳-3颗粒进行了测试,原子力3D图形显示,单基药表面比双芳-3高3-5倍,恒温条件测试结果表明,单基药从20%到8%为外层水,8%到5%为中层水,5%到0%为内层水,双芳-3从16.5%到5.3%为外层水,5.3%到3%为中层水,3%到0%为内层水。由火药表面水分特征,揭示了HF炸药在贮存时水分沉降原因,提出克服水分沉降的措施,含双芳-3浆状炸药加固水剂后,能使炸药的水分相差控制在要求的1%范围内。

核磁共振技术研究淀粉及其抗性淀粉中水分的流动性

利用核磁共振技术研究淀粉及其抗性淀粉中水分的流动性。结果表明:随着淀粉的性质发生变化,水分的流动性变化明显;与原淀粉相比,抗性淀粉的水合能力明显增加,持水能力和水分流动性均降低。从磁共振的角度考察,抗性淀粉中水分流动性低于其原淀粉中的水分流动性。

氟石粉适应水分限量的测定

采用流盘法测定散装氟石粉发生液化的流动水分点,并建立其适运水分限量TML(Transportable Moisture Limit)的检测方法。着重讨论该方法中两个应用难点,确定外力振动的必要次数以及判断液化的统一尺度。方法应用于测定中国不同产地氟石粉样品的TML值,重复性好,填补国内外对散装氟石粉TML检验研究的空白。

采后上部烟叶干燥过程水分扩散能力与流动性的关系

【目的】探究采后上部烟叶干燥过程水分扩散能力与流动性的关系,为揭示烟叶干燥过程水分迁移扩散机理提供理论依据。【方法】以上部烟叶为试验材料,进行不同温度(35、40、45、50、55、60和65℃)干燥试验,分析采后烟叶、叶片和主脉的干燥特性及水分扩散系数,利用低场核磁共振技术检测叶片和主脉水分状态变化。【结果】烟叶、叶片和主脉的含水率在干燥初期下降较快,后期下降较慢,均呈典型的降速干燥特征,叶片干燥速率大于主脉。烟叶、叶片和主脉的水分扩散系数均随着温度及含水率的升高呈增大趋势,主脉的水分扩散能力远大于叶片。随着干燥过程的进行,叶片和主脉自由水的弛豫时间均逐渐减小,表明其流动性逐渐减弱,而干燥过程中主脉的自由水的流动性强于叶片。干燥开始时叶片和主脉中均以自由水含量较高,随着含水率的降低,自由水含量同步下降,表明自由水的散失主导了叶片和主脉的干燥过程,而叶片和主脉的半结合水含量在中后期或后期才明显下降。叶片和主脉的水分扩散系数与自由水含量及其弛豫时间均呈极显著正相关(P<0.01),可利用自由水流动性的强弱衡量叶片和主脉水分扩散能力的大小。【结论】采后烟叶及其叶片和主脉的干燥过程受内部水分扩散控制,其水分扩散能力主要与温度、含水率及自由水流动性有关。

适运水分极限测定——流盘试验方法讨论

通过对流盘试验方法测定适运水分极限的讨论，观察水分含量与直径变化的相关性；同时，以快速测定近似流动水分点方法为依托，寻找样品流动水分点对应直径增量大概范围，寻找到人工判断流动水分点便捷有效的识别方法。

基于福建可门港区进口精矿的适运水分极限研究

为实现进口精矿的海上安全运输,采用流盘法及压入实验法对福建可门港区进口的各种铁矿砂精矿进行流动水分的测定,并对其分类和多次检测,为各矿种的安全转泊建立数据库,填补国内对各铁矿流动水分点检测无数据支持的空白,并对影响铁矿砂流动水分点的可能因素进行分析,为铁矿砂及精矿的安全转泊提供依据及建议。

粒度分布对铁矿粉适运水分限量的影响研究

为保证承运散装铁矿船舶的运输安全,IMO《IMSBC规则》03-15修正案加强了对铁矿粉的监管要求,附件中增加了铁矿粉细目。本文根据以往铁矿粉的适运水分限量的检验经验和测试结果,在总结铁矿粉的适运水分限量随其粒度的变化规律的基础上,针对巴西铁矿粉进一步研究了影响铁矿粉流态的关键粒级,以及流动水分点随粒级变化的变化规律,并根据研究结果提出了对承运散装铁矿船的一些监管建议。

苦瓜微波-热风振动床干燥湿热特性与表观形态研究

为探索热风对苦瓜片微波干燥特性、湿热特性与表观形态的影响,利用微波-热风振动流化床干燥机,研究了新鲜苦瓜片在不同微波-热风组合方式下的干燥动力学特性、热像变化、水分状态分布、色泽以及微观结构的变化。试验结果表明:热风对微波振动流化床干燥有显著影响,微波0.6 W/g、微波0.6 W/g+热风60℃+风速3 m/s、微波0.6 W/g+热风70℃+风速6 m/s比单独热风70℃+风速3 m/s的干燥时间分别缩短56.4%、70.5%和75.6%。在表观形态上,单独热风干燥的脱水苦瓜片与新鲜苦瓜片色泽最为接近,两组微波-热风组合干燥所得样品色泽优于单独微波干燥。在湿热特性上,微波-热风组合干燥后期物料温度均匀性显著优于单独微波干燥,4种干燥方式下NMR波谱下的水分信号逐渐降低,且主峰向左移,水分的活跃程度降低,MRI信号显示,热风能改善微波干燥过程中水分分布均匀性。扫描电镜观测表明,单独热风干燥对保持脱水苦瓜片细胞完整性效果最明显,微波-热风组合干燥的细胞完整性显著优于单独微波干燥。微波-热风组合振动流化床干燥工艺在保证被干物料品质前提下还极大提高了物料干燥效率,缩短了干燥时间。

核磁共振及其成像技术在面团形成过程中的研究

面团的形成是面制品生产过程中的重要工序，它的质量直接影响面制品的品质。核磁共振（Nuclear Magnetic Resonance，NMR）技术能直观、快速、精确地反映和体现面团在搅拌过程中水分迁移变化，通过磁共振成像（Magnetic Resonance Imaging，MRI）技术观察面团面筋网络的形成和破坏过程，采用多成分模型分析质子弛豫曲线，将面团中的水分划分为三部分，具有各自不同的自旋-自旋弛豫时间，分别为T21、T22和T23。随着和面时间的延长，面团的他值和质子信号幅度（A）发生相应的变化。研究结果发现，面团的NMR弛豫参数的变化规律，以及面团形成过程的所体现的MR图像对指导和评价工业化面团形成所需要的最佳搅拌时间具有重要意义。实验结果表明：当中速搅拌，水分添加量为面粉的45％，其水温为30℃时，低筋粉的和面时间为15～25min，其面团的质量最佳。

易流态化货物安全装运研究

文章结合理论研究和生产实际，介绍易流态化货物含水量、流动水分点和适运水分限的测定原则，提出了易流态化货物适运性判定方法，总结了此类货物装运及管理的注意事项，供广大海员在生产中参考应用。

A Modified Groundwater Module in SWAT for Improved Streamflow Simulation in a Large, Arid Endorheic River Watershed in Northwest China

Interactions between surface water and groundwater are dynamic and complex in large endorheic river watersheds in Northwest China due to the influence of both irrigation practices and the local terrain. These interactions interchange numerous times throughout the middle reaches, making streamflow simulation a challenge in endorheic river watersheds. In this study, we modified the linear-reservoir groundwater module in SWAT(Soil and Water Assessment Tools, a widely used hydrological model) with a new nonlinear relationship to better represent groundwater processes; we then applied the original SWAT and modified SWAT to the Heihe River Watershed, the second largest endorheic river watershed in Northwest China, to simulate streamflow. After calibrating both the original SWAT model and the modified SWAT model, we analyzed model performance during two periods: an irrigation period and a non-irrigation period. Our results show that the modified SWAT model with the nonlinear groundwater module performed significantly better during both the irrigation and non-irrigation periods. Moreover, after comparing different runoff components simulated by the two models, the results show that, after the implementation of the new nonlinear groundwater module in SWAT, proportions of runoff components changed-and the groundwater flow had significantly increased, dominating the discharge season. Therefore, SWAT coupled with the non-linear groundwater module represents the complex hydrological process in the study area more realistically. Moreover, the results for various runoff components simulated by the modified SWAT models can be used to describe the hydrological characteristics of lowland areas. This indicates that the modified SWAT model is applicable to simulate complex hydrological process of arid endorheic rivers.

船舶承运镍矿石安全建议

为有效防范船载镍矿石事故发生,针对近年来多起承载镍矿石船舶的倾覆事故,分析镍矿石原产地情况,提出船舶载运矿石事故防范措施:托运人在装货前,应尽早向承运人以书面形式提供与货物相关的所有信息及证明文件,以保障货物装船、运输及卸载安全;承运人应始终恪尽职守,监督装船作业,在发现货物状况有可能影响船舶安全时,应及时拒绝或停止装载货物,并委托符合资质的检验员代为协助处理相关事宜;从源头抓起,明确租船合同中托运人与承运人的责任和义务,尽力规避风险,以保障船舶安全,避免事故发生。

高中生物实验改进点滴

本人对全日制高级中学教科书<生物>中的实验进行部分改进,实验效果很好,现整理出来与大家探讨.

散货船装载易流态化货物运输

文章从易流态化货物含水量、流动水分点、适运水分极限、含水量测试程序,以及IMSBC CODE中列明的、常见的几种易流态化货物对船舶运输的影响进行分析,规范了船舶装载易流态化货物操作流程,建立了风险评估和风险管理有效机制,确保船舶运输安全。

Numerical Analysis of the Flow Field in a Sloshing Tank with a Horizontal Perforated Plate

Liquid sloshing is a type of free surface flow inside a partially filled water tank.Sloshing exerts a significant effect on the safety of liquid transport systems;in particular,it may cause large hydrodynamic loads when the frequency of the tank motion is close to the natural frequency of the tank.Perforated plates have recently been used to suppress the violent movement of liquids in a sloshing tank at resonant conditions.In this study,a numerical model based on OpenF OAM(Open Source Field Operation and Manipulation),an open source computed fluid dynamic code,is used to investigate resonant sloshing in a swaying tank with a submerged horizontal perforated plate.The numerical results of the free surface elevations are first verified using experimental data,and then the flow characteristics around the perforated plate and the fluid velocity distribution in the entire tank are examined using numerical examples.The results clearly show differences in sloshing motions under first-order and third-order resonant frequencies.This study provides a better understanding of the energy dissipation mechanism of a horizontal perforated plate in a swaying tank.

Effects of Moisture on Rheological Properties of PAV Aged Asphalt Binders

For the most coastal areas where the air is very humid,study on the effect of humidity on the performance of asphalt has its practical significance.However,limited research has been done to investigate the effect of humidity on rheological properties of asphalt.In this study,asphalt binders were aged in the pressure aging vessel(PAV)under different conditions of moisture and aging time.Then Dynamic Shear Rheometer(DSR)and Bending Beam Rheometer(BBR)measurements were conducted to obtain the parameters relating to the complex modulus,phase angle,failure temperature,and creep stiffness.It was found that the low temperature performance decreased as evidenced by the results of the creep stiffness.While there were no significant differences among conditioned binders based on complex modulus G*and phase angleδ,it was found that theδvalue increased when the humidity increased from 0% to 80% ,and then theδvalue decreased when the humidity increased to 100% .In addition,the results of the failure temperature indicated that the humidity of 80% would be a critical point for the high temperature performance of the asphalt binders.

渗透作用演示实验装置的改进

现行高二年级生物课本（人民教育出版社)第58～59页中“渗透作用与水分的流动”演示实验，凡上过该教材的教师都知道，若按课本及教学参考书的要求进行实验．存在一个很大的问题：虽然半透膜的制取很容易(可用花生种皮、猪肠衣、牛皮纸等作为半透膜进行实验)，但是要在漏斗口处密封上半透膜却很难。

Molecular dynamics simulation of water transport through graphene-based nanopores: Flow behavior and structure characteristics

The flow behavior of pressure-driven water infiltration through graphene-based slit nanopores has been studied by molecular simulation.The simulated flow rate is close to the experimental values,which demonstrates the reasonability of simulation results.Water molecules can spontaneously infiltrate into the nanopores,but an external driving force is generally required to pass through the whole pores.The exit of nanopore has a large obstruction on the water effusion.The flow velocity within the graphene nanochannels does not display monotonous dependence upon the pore width,indicating that the flow is related to the microscopic structures of water confined in the nanopores.Extensive structures of confined water are characterized in order to understand the flow behavior.This simulation improves the understanding of graphene-based nanofluidics,which helps in developing a new type of membrane separation technique.

严防镍矿运输风险升温

2016年6月中旬,菲律宾三描礼士地区进入雨季,开始了20天左右的持续降雨。原本寸草不生的该镍矿产区地面骤然充盈起了丰沛的雨水,这不免再次触碰到了承运人最为关心的安全环节。并非杞人忧天,因为就在近日,在菲律宾装载镍矿的某船,还因拒装水分含量明显偏高的货物而遭到菲律宾当地海岸警卫队（Philippine Coast Guard/PCG）人员的干涉。

The properties of dilute debris flow and hyper-concentrated flow in different flow regimes in open channels

Particle Image Velocimetry(PIV) technique was used to test the analogues of hyperconcentrated flow and dilute debris flow in an open flume. Flow fields, velocity profiles and turbulent parameters were obtained under different conditions. Results show that the flow regime depends on coarse grain concentration. Slurry with high fine grain concentration but lacking of coarse grains behaves as a laminar flow. Dilute debris flows containing coarse grains are generally turbulent flows. Streamlines are parallel and velocity values are large in laminar flows. However, in turbulent flows the velocity diminishes in line with the intense mixing of liquid and eddies occurring. The velocity profiles of laminar flow accord with the parabolic distribution law. When the flow is in a transitional regime, velocity profiles deviate slightly from the parabolic law. Turbulent flow has an approximately uniform distribution of velocity and turbulent kinetic energy. The ratio of turbulent kinetic energy to the kinetic energy of time-averaged flow is the internal cause determining the flow regime: laminar flow(k/K<0.1); transitional flow(0.1< k/K<1); and turbulent flow(k/K>1). Turbulent kinetic energy firstly increases with increasing coarse grain concentration and then decreases owing to the suppression of turbulence by the high concentration of coarse grains. This variation is also influenced by coarse grain size and channel slope. The results contribute to the modeling of debris flow and hyperconcentrated flow.