检索结果-南通市图书馆

Use of zeolitized coal fly ash in the simultaneous removal of ammonium and phosphate from aqueous solution

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2007年第2期1卷 213-220页

作者： WU Deyi HU Zhanbo wang xinze HE Shengbing KONG Hainan School of Environmental Science and Engineering Shanghai JiaoTong UniversityShanghai 200240China

Discharge of wastewater containing nitrogen and phosphate can cause ***,the development of an efficient material for the immobilization of the nutrients is *** this study,a low calcium fly ash and high calcium fly ash were converted into zeolite using the hydrothermal *** removal of ammonium and phosphate that coexist in aqueous solution by the synthesized zeolites were *** results showed that zeolitized fly ash could efficiently eliminate ammonium and phosphate at the same *** of zeolite with Ca^(2+)rather than Na+favored the removal of both ammonium and phosphate because the cation exchange reaction by the NH_(4)^(+)resulted in the release of Ca2+into the solution and precipitation of Ca^(2+)with PO_(4)^(3−)*** increase in the temperature elevated the immobilization of phosphate whereas it abated the removal of *** 60%removal efficiency for ammonium was achieved in the neutral pH range from 5.5 to 10.5,while the increase or decrease in pH out of the neutral range lowered the *** contrast,the removal of phosphate approached 100%at a pH lower than 5.0 or higher than 9.0,and less phosphate was immobilized at neutral ***,there was still a narrow pH range from 9.0 to 10.5 favoring the removal of both ammonium and *** was concluded that the removal of ammonium was caused by cation exchange;the contribution of NH3 volatilization to immobilization at alkaline conditions(up to pH level of 11.4)was *** respect to phosphate immobilization,the mechanism was mainly the formation of precipitate as Ca_(3)(PO_(4))_(2) within the basic pH range or as FePO_(4) and AlPO_(4) within acidic pH range.

关键词： fly ash zeolite ammonium phosphate removal

Valence electron structures dependences of structural stability and properties of REX_(3)(RE=rare earth;X=In,Tl)and RE(In,Co)3 alloys

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第11期33卷 331-339页

作者： Boyang Li Yongquan Guo Yi-Chen Feng xinze wang Wei Liu School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China

Intermetallic compounds REIn3(RE=rare earth)have attracted much attention due to their unique characteristics:crystal field effect,Kondo effect,superconductivity,heavy fermion,and antiferromagnetism,and their cobalt diluted alloys exhibit the ferromagnetic half-metallic characteristics at room *** this study,an empirical electron theory(EET)is employed to investigate systemically the valence electronic structure,the thermal and magnetic properties of REX_(3) and their cobalt diluted alloys for revealing the mechanism of physical *** calculated bond length,melting point,and magnetic moment match the experimental ones very *** study reveals that structural stability and physical properties of REX_(3) and their cobalt dilute alloys are strongly related to their valence electron *** is suggested that the structural stability and cohesive energy depend upon the covalent electron,the melting point is modulated by covalent electron pair,and the magnetic moment is originated from 3d magnetic *** ferromagnetic characteristics of Co-diluted REIn3 alloys is originated from the introduction of strong ferromagnetic Co atom,but,a competition is caused between the electron transition from valence electron to magnetic electron on d orbit and its reversal electron transformation with increasing the content of cobalt,which results in the formations of diluted magnetic Gd(In,Co)3 alloy with minor amount of cobalt and strong magnetic Nd(In,Co)3 alloy with doping more Co atoms.

关键词： REX_(3) cobalt dilute alloy valence electron structures empirical electron theory moment

Variation of phytoplankton community before an induced cyanobacterial(Arthrospira platensis) bloom

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2009年第12期21卷 1632-1638页

作者： wang Chong, HUANG Yingying, HE Shengbing, LIN Yan, wang xinze, KONG Hainan School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China. School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

A cyanobacterial （Arthrospira platensis） bloom was induced in situ by nutrient manipulation in an enclosure. The succession of the phytoplankton community and the water chemistry variations before the appearance of bloom, as well as their relationship, were investigated. The cell pigment variations were studied simultaneously. The Pearson＇s correlation analysis showed that there was no significant correlation between water chemistry and green algal or cyanobacterial composition, indicating that water chemistry variations were not suitable to be used as indicators for cyanobacterial-bloom early-warning. However, the diversity index of the phytoplankton community decreased sharply before the bloom appeared. Therefore, the dynamics of phytoplankton community was put forward to be an indicator for cyanobacterial-bloom early-warning. In addition, the cell pigment variations represented the changes of community structure, which should be useful for studying the dynamics of phytoplankton community.

关键词： bloom cyanobacteria community pigments early-warning

Phosphate removal and recovery through crystallization of hydroxyapatite using xonotlite as seed crystal

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2009年第5期21卷 575-580页

作者： CHEN Xuechu, KONG Hainan, WU Deyi, wang xinze, LIN Yongyong School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

Xonotlite was synthesized and tested for phosphate removal and recovery from synthetic solution in a batch mode. The effects of pH, initial calcium concentration, bicarbonate concentration on phosphate removal through crystallization were examined. The morphology and X-ray diffraction （XRD） pattern of xonotlite before and after crystallization confirmed the formation of crystalline hydroxyapatite. The results indicated that the crystallization product had a very high P content （〉 10%）, which is comparable to phosphate rock at the dosage of 50-200 mg xonotlite per liter, with a maximum P content of 16.7%. The kinetics of phosphate removal followed the second-order reaction equation. The phosphate removal ability increased with increasing pH. The precipitation of calcium phosphate took place when pH was higher than 7.2, whereas the crystallization occurred at pH 6.0. A high calcium concentration could promote the removal of phosphate via crystallization, while a high bicarbonate concentration also enhanced phosphate removal, through that the pH was increased and thus induced the precipitation process. When xonotlite was used to remove phosphate from wastewater, the removal efficiency could reach 91.3% after 24 h reaction, with removal capacity 137 mg/g. The results indicated that xonotlite might be used as an effective crystal seed for the removal and recovery of phosphate from aqueous solution.

关键词： phosphate recovery crystallization xonotlite

在线全文

学校读者我要写书评

暂无评论

钢管混凝土拱桥环境温度引起的应力挠度分析

铁道建筑 2016年第2期56卷 39-42页

作者：王新泽中铁十八局集团第二工程有限公司河北唐山063000

分析了钢管混凝土拱的挠度和拱趾处应力随环境温度改变而产生的变化。结果表明:环境温度引起的轴向应力和拱肋自重引起的轴向应力绝对值均不超过100 MPa;拱肋截面应力变化并非同步,而是存在一个弯曲效应,环境温度每变化5℃引起拱顶竖向... 详细信息

分析了钢管混凝土拱的挠度和拱趾处应力随环境温度改变而产生的变化。结果表明:环境温度引起的轴向应力和拱肋自重引起的轴向应力绝对值均不超过100 MPa;拱肋截面应力变化并非同步,而是存在一个弯曲效应,环境温度每变化5℃引起拱顶竖向位移变化17 mm;由当地最高温度引起的拱顶挠度变化为向上55.6 mm,由当地最低温度引起的拱顶挠度变化为向下135.6 mm;由环境温度变化引起的竖向高差不均匀是高速列车行驶的安全隐患,不可忽略。

关键词：钢管混凝土拱桥环境温度挠度温度应力西溪河大桥

在线全文

学校读者我要写书评

暂无评论

创新集成电路产业保险模式

中国金融 2023年第18期 49-50页

作者：王鑫泽解辉国家金融监督管理总局上海监管局

举保险行业力量支持中国集成电路产业自主创新发展,意义重大。在传统保险模式下中国保险业的承保能力不能适应集成电路产业高投入、高保额、高技术和自主可控要求,保险供需不平衡不充分的矛盾逐步显现。金融监管部门引导组建中国集成电... 详细信息

举保险行业力量支持中国集成电路产业自主创新发展,意义重大。在传统保险模式下中国保险业的承保能力不能适应集成电路产业高投入、高保额、高技术和自主可控要求,保险供需不平衡不充分的矛盾逐步显现。金融监管部门引导组建中国集成电路共保体(以下简称集共体),聚焦突出问题,通过一系列创新,以市场化运作方式,整合国内保险公司承保能力,提出特殊风险领域的解决方案,协助构建自主、安全、可控的中国集成电路产业链和供应链,走出一条“国之大者”的保险新路。

关键词：集成电路产业承保能力供需不平衡金融监管部门保险行业自主创新发展保险模式特殊风险

在线全文

学校读者我要写书评

暂无评论

我国数据交易研究进展:系统性文献综述

情报杂志 2022年第11期41卷 137-143页

作者：付熙雯王新泽西北大学公共管理学院西安710127

[研究目的]作为数据要素市场化配置的重要环节,数据交易在近年来受到国内学界广泛关注,通过对国内相关文献进行梳理,识别当前研究进展与薄弱环节,为未来研究提供参考。[研究方法]采用系统性文献综述法,通过内容分析和文献编码,展现国内... 详细信息

[研究目的]作为数据要素市场化配置的重要环节,数据交易在近年来受到国内学界广泛关注,通过对国内相关文献进行梳理,识别当前研究进展与薄弱环节,为未来研究提供参考。[研究方法]采用系统性文献综述法,通过内容分析和文献编码,展现国内研究现状与不足,并提出未来研究方向。[研究结论]国内学者的研究主要集中在数据交易的基本内涵、交易范围、影响因素及发展路径四个方面。研究发现,国内文献对数据交易的内涵与范围界定不清;缺乏对数据交易现状、影响因素及其作用机理的实证研究;对数据确权必要性和可操作性的研究缺乏深度。此外,研究视角和研究方法较为单一。未来可从多学科视角出发,就数据交易的内涵、影响因素的作用机理和数据确权的实现路径等进行深入探究。

关键词：数据交易交易范围数据要素市场系统性文献综述

基于YOLOv8n的轻量级巴旦木果实识别方法

在线全文

学校读者我要写书评

暂无评论

江苏农业学报 2024年第9期40卷 1662-1670页

作者：方国文何超王鑫泽西南林业大学机械与交通学院云南昆明650000

在果园环境下,快速精准识别巴旦木果实对提升巴旦木采摘机器人的作业精度和效率至关重要。为减少果园场景中因树叶遮挡或果实重叠导致的巴旦木果实漏检现象,降低计算量和参数量,提高果实识别模型的性能和准确度,本研究在YOLOv8n模型的... 详细信息

在果园环境下,快速精准识别巴旦木果实对提升巴旦木采摘机器人的作业精度和效率至关重要。为减少果园场景中因树叶遮挡或果实重叠导致的巴旦木果实漏检现象,降低计算量和参数量,提高果实识别模型的性能和准确度,本研究在YOLOv8n模型的基础上,利用ContextGuide模块替换原模型中主干网络(Backbone)部分基本构成单元C2f中的Bottleneck模块,利用BiFPN模块替代原模型中颈部网络(Neck)部分中的PANet模块,同时引入MPDIoU损失函数替换原模型中的CIoU损失函数,提出了一种改进的轻量级巴旦木果实检测模型(YOLOv8n-BCG)。并利用公开的巴旦木影像数据集对优化后的模型性能进行比较分析。结果表明,改进后模型参数量仅为1.528 M,平均精度值(mAP 0.50∶0.95)为69.7%,相比于原YOLOv8n模型提升0.5个百分点。与YOLOv5s、YOLOv5n、YOLOv7-tiny、Faster R-CNN等模型相比,YOLOv8n-BCG模型具有更低的浮点计算量和更高的检测精度值。本研究结果可为高效的巴旦木果实采摘机器人自动化作业提供技术支持。

关键词：巴旦木果实识别 BiFPN ContextGuide MPDIoU损失函数 YOLOv8n

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

曝气生物滤池脱氮的研究进展

化工进展 2017年第3期36卷 1077-1083页

作者：朱加乐林燕王欣泽沈剑上海交通大学环境科学与工程学院上海200240

介绍了曝气生物滤池的种类、脱氮的原理以及在工业废水和生活污水处理方面的实际应用,总结了曝气生物滤池脱氮影响因素方面的国内外研究成果,其中影响因素包括气水比、水力负荷、HRT、C/N、反冲洗、pH和滤料等。本文还综合考虑了成本和... 详细信息

介绍了曝气生物滤池的种类、脱氮的原理以及在工业废水和生活污水处理方面的实际应用,总结了曝气生物滤池脱氮影响因素方面的国内外研究成果,其中影响因素包括气水比、水力负荷、HRT、C/N、反冲洗、pH和滤料等。本文还综合考虑了成本和处理效果等问题,给出了各个影响因素的适宜范围。此外,本文还指出了曝气生物滤池技术目前在脱氮方面所存在的两个关键性问题——反硝化碳源不足和缺氧区域形成受限等问题,并提出了能够解决这两个问题的3种改良工艺——释碳材料、异养硝化好氧反硝化脱氮和曝气生物滤池组合工艺等,同时还介绍了这3种工艺在曝气生物滤池脱氮方面的研究成果、具有的优势以及目前存在的主要问题。此外,还对曝气生物滤池技术在脱氮方面的前景进行了展望。

关键词：曝气生物滤池脱氮影响因素改良工艺