Modeling Date Palm Trunk Fibers (DPTF) Packed Bed Adsorption Performances for Cadmium Removal from Aqueous Wastewater

In this study,the potential of a low-cost bio-adsorbent,taken directly from Date Palm Trunk Fibers(DPTF)agricultural wastes,for cadmium ions removal from wastewaters is examined.The performances of this adsorbent are evaluated by building breakthrough curves at different bed heights and flow rates while keeping other parameters,such as the initial feed concentration,pH,and particle size,constant.The results indicate that the maximum cadmium adsorption capacity of DTPF can be obtained from the Thomas model as 51.5 mg/g with the most extended mass transfer zone of 83 min at the lowest flow rate at 5 ml/min.The saturation concentrations(NO)and the rate constant(kab)obtained from the BDST(bed depth service time)model are 7022.16 mg/l and 0.0536 l/mg.min,respectively.Using the Yon-Nelsen Model,it is found that operating at a lower flow rate leads to a larger value of the elapsed needed time to reach a 50%breakthrough.The Wolborska model indicates that the bed capacity increases with decreasing the flow rate,and the adsorbent can achieve a greater external mass transfer kinetic coefficient(2.271/min)at a higher flow rate.

Date palm kernel-based GAC and its dynamic modeling of residual chlorine breakthrough curve in multimedia filter

First, the date palm kernel is used to produce granular activated carbon （GAC） by a physiochemical activation process. The process involves six steps： washing, drying, crushing, sieving, carbonization, and activation. Secondly, the ability of the produced GAC to remove pollutants is examined through batch experiments of residual chlorine adsorption whereas the equilibrium isotherm experimental data are tested for the Langmuir and Freundlich isotherms equations. Thirdly, the experimental and theoretical study of dynamic adsorption process and the effect of major operating parameters on dynamic adsorption are investigated. The results show that the Langmuir isotherm gives the best fitting to experimental data, which indicates that the residual chlorine adsorption can be characterized by mono layer adsorption behavior. The produced GAC has a great potential as an adsorbent for residual chlorine in water systems and it can compete favorably with the conventional adsorbents. The Thomas extended model with combined mass transfer resistances is used for verifying the experimental results and the results show that the proposed model coincides well with the experimental data of the dynamic adsorption process.

A Dynamic Knowledge Model for Design of Suitable Sowing Date and Sowing Rate in Winter Wheat

Based on research concerning dynamic relationships of winter wheat growth to environments and production conditions, a winter wheat model for selecting suitable sowing date, population density and sowing rate under different varieties, spatial and temporal environments was developed. Case studies on sowing date with the data sets of five different eco-sites, three climatic years and soil fertility levels, and on population density and sowing rate with the data sets of two different variety types, three different soil types, soil fertility levels, sowing dates and grain yield levels indicate a good model performance for decision-making.

Evaluation of the CROPGRO-Peanut model in simulating appropriate sowing date and phosphorus fertilizer application rate for peanut in a subtropical region of eastern India

Projected changes in weather parameters, mainly temperature and rainfall, have already started to show their effect on agricultural production. To cope with the changing scenarios, adoption of appropriate management strategies is of paramount importance. A study was undertaken to evaluate the most appropriate combination of sowing date and phosphorus fertilization level for peanut crops grown in sandy loam soil in a subhumid region of eastern India. Field experiments were conducted during the summer seasons of 2012 and 2013 on peanut crops at the farm of the Indian Institute of Technology, Kharagpur. The DSSAT v4.5 CROPGRO-Peanut model was used to predict the phenology, growth, and yield of peanut crop under combinations of four sowing dates and four phosphorus fertilization levels. The model was calibrated with a 2012 dataset of growth, phenology, and yield parameters for estimating the genetic coefficients of cultivar TMV-2 and was validated with a 2013 dataset of the same parameters. Simulations of pod yield and other yield parameters using the calibrated model were found to be quite accurate. The model was able to reasonably simulate pod yield and final biomass with low normalized root mean square error (RMSE_n), low absolute root mean square error (RMSE_a) and high coefficient of determination (R^2> 0.7) over a wide range of sowing dates and different phosphorus fertilization levels sensitivity analysis indicated that sowing from the second week of January to the end of February with 30–50 kg P_2O_5 ha^(-1)would give the highest pod yield.

Dating Model of Illite Grain Rb-Sr Isochron and Its Application to Precambrian Stratigraphy

This paper discusses the Rb-Sr geochemical behaviour of illites in the sedimentary process, and points out that illites of the lmd and lm types could reach Sr-isotopic equilibrium with its environmental medium during the sedimentary process and initial stage of diagenesis, and illite grains of different sizes have various Rb contents. A new dating method for sedimentary rocks----a dating model of illite grain Rb-Sr isochron----is established, in consideration of the geochemical process of Sr-isotopic homogenization and differentiation in the course of their formation and evolution. In addition, the paper concerns the application of the dating model to the Precambrian unmetamorphosed sedimentary rocks in western Henan Province, which gives satisfactory results coincident with the geological facts.

Kinetic Modelling of Liquid-Phase Adsorption of Sulfate onto Raw Date Palm Seeds

Adsorption kinetics in multi-component systems has been a subject of intensive research because it is of both theoretical and practical importance. In this paper, raw date palm seeds （RDPS） were investigated to assess the possible use of this raw material as an effective adsorbent for the removal of sulfate from aqueous solution. The influence of various parameters such as sulfate initial concentration, pH, adsorbent dose and stirring time has been studied for the adsorption of sulfate in batch mode. Effects of foreign anions on the adsorption of sulfate onto RDPS have been also investigated. The pseudo-second-order, Elovich and intraparticle diffusion kinetic models have been developed to predict the rate constants of adsorption and equilibrium capacities. The maximum adsorption capacity of sulfate （qe ≈3.2 mg/g） onto RDPS was reached for the initial sulfate concentration = 100 mg/L, pH - 3.5, adsorbent dose = 10 g/L and for a stirring intensity = 200 rpm at 25 ± 2 ℃. The results showed that the adsorption of sulfate onto this raw materials followed pseudo-second-order rate kinetic predicting a chemisorption process.

核动力系统分析中细管簇当量元件阻力

为研究不同工况下核动力系统主管路的参数变化,需选择合适的阻力元件当量代替部件内部细管簇的流动阻力.根据流体流动规律,设计了一种圆弧渐缩渐扩式当量阻力元件,采用标准k-ε湍流模型探究该阻力元件对圆管内部流动的影响,对比分析得到阻力系数ζ与缩径比d/D和阻力元件长度L的基本规律,最后拟合并验证所得关系式.结果表明:该阻力元件对下游管道影响相对较小,可用于当量代替复杂部件内部流动阻力;排除雷诺数Re对该元件阻力系数ζ的影响,ζ与d/D和L均呈负相关,且d/D越小,L越短,中心轴向速度和湍动能变化越大,下游恢复区长度就越长;经验证,Re>3.0×106,d/D=0.5~0.9时,拟合的指数函数关系式预测的ζ更准确,并且该指数函数能够实现某蒸汽发生器内部细管簇的简化.

1951–2021年欧洲地区木本植物的格网物候数据集

植物物候记录了植物重复生命周期事件的发生时间,是指示全球变化的重要指标。植物物候研究有助于理解生态系统对全球变化的响应,也是模拟陆地生态系统的物质和能量平衡的重要基础。本数据集基于过去70年欧洲物候项目(Pan European Phenology Project,PEP725)整编的6种代表性木本植物的地面观测物候数据,采用三种考虑春季冷激和积温累积过程的物候模型(Unified、Unichill和时空耦合模型)在大洲尺度上对物候数据进行建模和分析,研制了欧洲地区代表性木本植物格网物候数据集。本数据集包含1951–2021年欧洲地区(34°57′N–72°3′N,25°3′W–40°3′E)6种木本植物的逐年展叶始期和开花始期格网数据,空间分辨率为0.1°,时间分辨率为天。数据集的质量评估表明,欧洲地区各物种展叶始期和开花始期平均误差分别为7.9和7.6天,与其他区域尺度研究中春季物候的模拟误差接近,因此本文格网物候数据具有较高的模拟精度。本数据集旨在更好地表征欧洲地区大洲尺度植物物候的时空格局,为区域其他来源的植物物候数据产品提供有价值的验证参考,亦可为全球变化和陆地生态系统模拟等研究领域提供支撑物候数据。

不同降水年型下旱地春小麦产量及其构成因素对播期和日均温度变化响应的模拟分析

为探讨播期调控及降水量和日均温度变化对旱地春小产量及其构成因素的耦合效应,基于甘肃省陇中地区气象数据、土壤数据和管理数据,通过APSIM模型对不同播期及日均温度变化情景下春小麦产量和生物量进行模拟分析,并利用试验区2013-2018年大田试验的春小麦产量及生物量数据对该模型进行适用性验证。结果表明,春小麦模拟产量及生物量的NRMSE均在8%以内,模型的有效性均大于0.80,说明模型具有较高的准确度和适用性。使用1970-2018年研究区的气象及土壤数据,设置不同播期及日均温度变化的模拟情景[早播(3月3日)、正常播(3月18日)、晚播(3月31日);日平均温度变化范围为降温2.0℃~增温2.0℃,以温度变化量1℃为1个梯度],经回归分析,小麦产量受影响程度表现为降水量>温度>播期,相同气候条件下小麦产量均表现为正常播>早播>晚播。春小麦在湿润年、正常播、日均温度降低2.0℃的条件下可获得最高产量。降水量对春小麦千粒重和籽粒数分别表现出负效应和正效应,温度则分别表现出正效应和负效应,千粒重和籽粒数均随着播期的推迟先增加后减少。综合分析,降水增多可通过增加春小麦籽粒数来提高产量;当地春小麦宜在3月中旬播种且应注重防寒与蓄水保墒,以促进小麦的高产与稳产。

工业机器人整机性能影响因素及评估模型优化

工业机器人整机性能的综合评估涉及核心零部件、工况条件与环境因素等输入条件和准确度、重复性与超调量等输出条件,待评估参数众多且各因素之间存在复杂的耦合关系,理论建模方式存在无法统一表征或表征不全面等问题。数据驱动建模对大量的试验数据信息进行挖掘,综合考虑输入中所包含的各种因素对机器人整机性能的影响,能够较为准确地反映输入输出间的映射关系。本研究结合理论分析手段,把控各影响因素对机器人整机性能的总体影响趋势与输入输出间的理论分布关系,并将分析结果用于指导数据驱动建模,最终建立工业机器人整机性能综合评估模型。

川北米仓山隆起构造-热演化特征

本文基于实测锆石(U-Th)/He和磷灰石裂变径迹年龄的联合热史模拟明确了米仓山隆起自新元古代以来的构造-热演化史。米仓山隆起前寒武系样品锆石(U-Th)/He年龄和磷灰石裂变径迹年龄分别为190~138 Ma和106.1~120.6 Ma,均小于地层年龄或成岩结晶年龄,有效地记录了早期热信息。热史模拟结果表明米仓山隆起自新元古代以来主要经历了早侏罗世—早白垩世和晚中新世至今两期快速冷却事件,分别与扬子-华北板块碰撞和印度-欧亚板块碰撞的东扩作用有关,而白垩纪—早中新世的缓慢冷却过程则与当时的古夷平面发育有关。本文不仅丰富完善了川北地区构造-热演化成果,而且对于该地区下一步油气勘探具有重要的指导意义。

春大豆合理播期确定动态知识模型构建

为提高春大豆播种期确定的时效性和准确性,利用农田信息采集系统获取土壤墒情及环境信息,并根据大豆播种进程与适宜环境、土壤墒情同步原理,采用隶属函数方法,将播种农艺要求与播种影响因素间的关系函数化,建立春大豆合理播期确定知识模型;并利用2个不同生态点的气象与土壤温湿度等参数,结合模型决策日期与2年中各地实际播期及出苗情况,对春大豆合理播期确定模型进行了实例验证。结果表明:2021年北15、2022年北14两块试验地播期确定模型输出结果与农田实际播期分别为4月23日、4月24日与5月7日、5月10日,月度误差分别为3.33%和9.68%,模型结果准确率分别为96.67%和90.32%。模型设计结果与当前高产春大豆实际农作制度体现较好的一致性和适用性,可以为农业生产者应用信息化手段确定春大豆播种期提供技术参考。

Metamorphic P-T conditions and ages of garnet-biotite schists in the Dahongshan Group from the southwestern Yangtze Block

The Dahongshan Group,situated at the southwestern margin of the Yangtze Block,represents a geological unit characterized by relatively high-grade metamorphism in the region.This paper investigates the garnet-biotite schist from the Laochanghe Formation of the Dahongshan Group,employing an integrated approach that includes petrological analysis,phase equilibrium modeling,and zircon U-Pb dating.The schist is mainly composed of garnet,biotite,plagioclase,quartz,rutile,and ilmenite.Phase equilibrium modeling revealed the peak metamorphic conditions of 8-9 kbar and 635-675°C.By further integrating the prograde metamorphic profile of garnet and geothermobarometric results,a clockwise P-T metamorphic evolution path is constructed,which includes an increase in temperature and pressure during the prograde stage.LA-ICP-MS zircon U-Pb dating and zircon Ti thermometry constrains the post-peak metamorphic age of 831.2±7.2 Ma.Integrated with previously reported results,it is revealed that the southwestern margin of the Yangtze Block experienced a large-scale regional metamorphism during the Neoproterozoic(890-750 Ma),which is related to the collisional orogenic process.This may be associated with the late-stage assembly of the Rodinia supercontinent or with local compression and subduction processes during the breakup of the Rodinia supercontinent.

流域生态系统健康状况评估的模型、数据源及发展方向浅析

流域生态系统是在流域尺度内各种环境生态特征的综合表征体系,其健康状况既反映了流域本身的生态环境质量,也反映了流域生态韧性。通过检索及归纳分析以往对流域生态系统健康评估的相关研究可以发现,评估模型和数据源是流域生态系统健康评估的关键。基于此,本文首先梳理了PSR(Pressure-State-Response)及其衍伸模型、水基系统评价模型、生物完整性指数法及《流域生态健康评估技术指南(试行)》中的等级评价体系法等4种常用模型或方法的内涵、应用及特点。进而,本文将数据源归纳为遥感数据、检测监测实时数据、相关统计数据三大类,并详细介绍了每一类数据源的内涵、优劣势、相关应用指标及应用前景。最后,本文从如何合理构建流域生态系统健康评估指标体系、评估数据的整合及应用潜力挖掘、前沿技术的转化应用等3个方面进行了展望分析。

新型城镇化与农民收入增长Panel Date模型分析

文中主要运用Panel Date模型来探讨新型城镇化与农民收入增长之间关系。研究表明:整体而言,城镇化与农民各种收入增长呈明显的正向相关性;从不同区域来看,城镇化率区域差异导致区域农民收入差异。

福建省城镇居民收入差距对消费影响的实证分析——基于Panel Date模型的分析

运用Panel Date模型,针对福建省不同收入阶层城镇居民收入差距对消费影响进行实证分析,得出收入差距对消费特别是消费支出具有显著影响,同时得出福建省消费结构不合理的结论。最后提出从提高收入、缩小收入差距与优化消费结构两方面促进福建城镇居民消费的政策建议。

刀具智能化管理服务系统开发设计

为满足日常生产的刀具业务管理规范化、刀具选配的合理便捷,针对车间现场的刀具管理服务需求,对刀具智能化管理服务进行研究。通过分析当前刀具管理技术现状,以现场业务流程及表单管理情况进行数据库设计,开发刀具智能化管理服务系统。同时,整合绘制刀具智能化管理服务系统E-R图,并根据现场刀具准备流程,融入科学刀具编码、刀具选配方法,实现车间现场与工艺室对刀具的实时数据监测与共享,合理优化了刀具管理方式并降低了管理成本开支,实现刀具管理智能化。

基于GPDA-IMM和时间管理的相控阵雷达多目标跟踪算法

多功能相控阵雷达具有灵活性强、跟踪能力强的优势。为了提高相控阵雷达目标跟踪器精确度,进行相控阵雷达能量调节和任务执行的科学管理,通过合理调整机动目标和非机动目标的回访率,进而实现搜索、跟踪时间资源管理。设计了广义概率数据关联-交互式多模型(Generalized Probability Data Association-Interacting Multiple Model, GPDA-IMM)算法,GPDA运算量小,IMM综合了无迹和容积卡尔曼滤波和粒子滤波多模型滤波的特点,且优化权重因子,达到了较好跟踪性能。最后,通过仿真平台模拟8个运动目标的现实场景,结合时间管理和目标跟踪调整回访率,进行大量的仿真实验,证明了算法对不同目标类型和机动状态的有效性和实用性。

基于逻辑模型的数据链体系架构框架设计与验证

架构设计是数据链体系构建中的核心,而逻辑架构模型构建与验证是数据链体系数字化和模型化设计的重要手段。首先,分析了采用逻辑模型开展体系架构设计的必要性,并从问题解决、领域需求和综合效能等角度对体系架构设计进行了归纳;然后,从体系级、系统级和装备级开展逻辑模型设计,并给出了每个层级的设计方法论、建模框架和工具语言;接着,展示了体系级向系统级传递以及系统级向装备级传递的具体模型;最后,给出了各层级独立闭环验证和跨层级逻辑闭环验证的方法。

基于网络安全防护技术的智控平台应用研究

可视化智控平台依托三维建模、大数据分析、虚拟仿真等先进技术,通过开放的系统接口,将生产管理、能源管理、设备运维等多个模块集成到同一软件平台下,形成一个统一的、关联的、智能的综合管理系统,实现了综合信息的高度共享。重点介绍了利用网络安全防护技术、数据融合与分析技术实现信息资源的有效融合与分析运用,为综合管控提供了一体化、整合式创新服务,提升了运营管理水平和产业服务水平,实现了对数据的全方位智能化管控。