Changing Process and Impact Factors of Ecosystem in Shuangtaizi Estuary Wetland of China

By introducing geological and natural conditions of Shuangtaizi Estuary Wetland,a national nature reserve,and borrowing Landsat5 TM wetland data of the year 1987 and 2005,the core area of Shuangtaizi Estuary Wetland is studied,areas of its natural water,mudflat,seepweed beach,culture zone,reservoir and swag,reed field,rice field and non-wetland landscape are respectively analyzed,as well as the changes of wetland community,water quality,waterfowl quantity and species.It is found that the study area is suffering from serious fragmentation of wetland,reducing reed yield,degrading water quality,decreasing bird species and amount,which implies that the degraded wetland environment has imposed threats on the survival of some wetland species.Root causes of such a result are analyzed from the perspectives of regional climate changes and human interventions;while regional climate changes include obvious temperature increase and precipitation decrease,human interventions include oil exploration,reclamation of land from the lake,overuse of biotic resources,environment pollution.Due to the interactive influence of these two factors,ecosystem of Shuangtaizi Estuary Wetland has experienced drastic changes,which should be attached sufficient importance by relevant departments so as to enhance its protection and management.

Laser Induced Photoelectron Impact Ionization In Multiphoton Ionization Process

Multiply charged ions of Ar and NO were observed in MPI experiment Of NO/Ar with TOF-MS. A delayable pulsed acceleration field wn applied tO investigate the effect of the photoelectrons on the formation of the multiply charged ions. The multiply charged ions were suggested to be produced by photoelectron impact ionization, in the region bentween the extractor grid and the repeller plate, step by step, from neutral species and lower charged ions. The 50-60ns of FWHM of the ion peaks implies that the pulse width of the photoelectrons should be shorter considering the broadening effect during the ionization process.

Effects on Sedimentary Processes via Upper Triassic Climate Forcing Caused by Multiple Impacting and Large Igneous Provinces (LIP)-Rifting/Degassing: Jordanian Platform/Arabian Plate and Germanic Basin/Central Europe

Upper Triassic sedimentary systems of both the Arabian Plate and the Germanic Basin reveal climate- and plate tectonic-forced effects through certain time-intervals experienced by architectural elements, lithofacies types, unconformities, flash flood deposits, maximum flooding surfaces/sequence boundary (MFS/SB), mineralogy, and isotope anomalies. Further, Moon recession and changes of Earth’s rotation velocity (core/mantle boundary) are associated with multiple impacting and large igneous provinces/Mid Oceanic Ridge Basalt, LIP/MORB-rifting/degassing. While acidification (by degassing, sturz-rain) does influence tectosilicates and carbonates, montmorillonite represents a key mineral as transformation of volcanic/impact glass (Tephra) to be found as co-components in and in certain pelite units as “boundary clay-suspicions” (mixture of eolian paleoloess, pelite, paleosol, and tephra → tuffite). Obviously, unconformities and sequence boundaries of both study areas separate and dislocate interrupted ∂13C and 87Sr/86Sr-data groups along the isotope curves. Both Proto-Arctic Ocean rifting/degassing comprising kimberlitic pyroclastic eruptions and Neotethys rifting/degassing as well as multiple impacting played the most important role during the Norian, followed by the incipient Central Atlantic Magmatic Provinces rifting since the Rhaetian. The following associations are encountered and dealt with in this study: Sequence boundaries-∂13C, maximum flooding surfaces-(FUCs)-∂13C, unconformities-plate motion, tephra-pelite-tuffite-montmorillonite. Norian: maximum flooding surfaces (MFSs)-“paleosol”/boundary clay?-rifting-volcanism, Moon/Earth data change. So the Norian (~221 - 206 Ma) hosts anomalous “amalgamated maximum flooding surfaces (MFSs)”, amalgamated paleosol (Jordanian Platform), multiple impacting (~219 - 214 Ma), the maximum opening of the Proto-Arctic Ocean (PAO) (~230 - 200 Ma), Neo-Tethys (NT)-subvolcanic (sills, dikes) in the NE Dead Sea area prior the Rhaetian, and a significant change of Earth/Moon relation data. The study concludes that rare and extreme events are very strongly shaping the geologic constellations in the Earth System.

基于IMPACT2002+的机械加工过程资源环境影响评价方法研究

为了科学地反映机械加工过程资源、能源以及环境排放情况,提出一种基于CML2001中间类型方法和Eco-indicator99损害类型方法相结合的IMPACT2002+生命周期影响评价方法。通过对中间环境影响指标和4种环境损害指标进行分析,建立机械加工过程资源消耗和环境排放数据量化、分析与评价体系以及评价模型;通过中间类型影响和损害类型影响的对比分析,可以更好地反映机械加工过程中资源消耗和环境排放情况以及环境影响与工艺的关系。以某机床厂全数控凸轮轴磨床零件丝杆螺母座的制造工艺过程为例,验证了该评价模型与评价方法的可行性。

Manufacturing Process Oriented Environmental Friendly Assessment with Fuzzy Analytic Hierarchy Process and Fuzzy Technique for Order Preference by Similarity to Ideal Solution

Green manufacturing is a mode to realize environmental friendliness by considering the environmental impact and energy consumption in manufacturing process.In order to make an environmental friendly assessment for manufacturing process,a multi-criteria decision making( MCDM) model combined with fuzzy analytic hierarchy process( FAHP) and fuzzy technique for order preference by similarity to ideal solution( FTOPSIS) is proposed in this work.The environmental and resource criteria and manufacturing process objects are identified as the first step.Then,the weights of the criteria are calculated by FAHP.Finally,based on experts' evaluation using fuzzy words,the manufacturing process objects are ranked by FTOPSIS.The proposed methodology is applied to a gear shaft manufacturing.The sensitivity analysis and comparisons are implemented to prove its robustness and effectiveness for the ecofriendly assessment for process objects.

Hydrogeochemical processes of thallium in a rural area of Southwest Guizhou,China

The water system in a rural area of Lanmuchang in Southwest Guizhou is facing a risk of thallium (Tl) contamination due to Tl mineralization around the area. The major trace elements and Tl in the water system are studied to understand the hydrogeochemical processes of Tl constrained by Tl mineralization. The results showed that the dispersion pattern of Tl follows a descending order in concentration from mine groundwater (deep groundwater) →stream water→shallow groundwater→background water, reflecting the impact of Tl mineralization on the hydrogeochemical composition. Tl concentrations in stream water in both regimes are remarkably higher (2-30 fold) downstream than up- and mid-streams, probably caused by the unidentified discharge of deep groundwater. Low Tl levels are detected in the current drinking water, however, the highly elevated Tl in stream water and ground water may pose a potential environmental risk through daily washing and agricultural irrigation. This study suggests that human activities, such as agricultural irrigation, could intensify the environmental risk of Tl.

预回火工艺对H13钢组织和性能的影响

对淬火后H13钢进行620,640,660,680℃下保温10,20,40min的预回火与600℃保温120min回火处理,并以常规回火(二次600℃保温120min回火)为对照,研究了预回火工艺对H13钢组织和性能的影响。结果表明:随着预回火温度提高或保温时间延长,H13钢中马氏体分解程度增加,残余奥氏体数量减少,析出碳化物尺寸增大,位错密度降低,H13钢的硬度降低,冲击吸收功增大;与常规回火相比,620,640℃下预回火10~20min+600℃回火后H13钢的位错密度更高,660,680℃下预回火10~40min+600℃回火后H13钢的的位错密度更低,660℃下预回火10~40min+600℃回火处理可以同时提高硬度和冲击韧性,其原因是较低位错密度和较小尺寸回火析出相的共同作用。

The Development of Intelligent Detector for Train Longitudinal Impact

This paper introduces a new kind of train impact detecting system that detect the train impact through detecting the train running acceleration,proposes that uniting the train running acceleration and the change rate of acceleration to token the train impact. The detector takes the portable computer as platform of data processing,utilizes the database technology to process data,making instrument Pc true,and improving the data processing ability of the instrument. The detector can show the train running acceleration on-line and real-timely,indicating the train impact situation directly,and uses the method that the software and hardware unifies to strengthen the system anti-jamming ability. At present,this detector has been tryout in some locomotive depots,each design function and the performance index conforms to request of the scene; the anti-jamming ability is strong,the monitor precision is reasonable,the detector can carry out the on-line examination to the train impact and monitoring the train running condition.

Microstructure,mechanical properties,and wear resistance of VCp-reinforced Fe-matrix composites treated by Q&P process

A quenching and partitioning(Q&P) process was applied to vanadium carbide particle(VCp)-reinforced Fe-matrix composites(VC-Fe-MCs) to obtain a multiphase microstructure comprising VC, V8 C7, M3 C, α-Fe, and γ-Fe. The effects of the austenitizing temperature and the quenching temperature on the microstructure, mechanical properties, and wear resistance of the VC-Fe-MCs were studied. The results show that the size of the carbide became coarse and that the shape of some particles began to transform from diffused graininess into a chrysanthemum-shaped structure with increasing austenitizing temperature. The microhardness decreased with increasing austenitizing temperature but substantially increased after wear testing compared with the microhardness before wear testing; the microhardness values improved by 20.0% ± 2.5%. Retained austenite enhanced the impact toughness and promoted the transformation-induced plasticity(TRIP) effect to improve wear resistance under certain load conditions.

Life cycle inventory analysis of CO_2 and SO_2 emission of imperial smelting process for Pb-Zn smelter

Based on the principle of life cycle assessment, CO2 and SO2 emission of Imperial Smelting Process in a certain zinc-lead smelter was analyzed by life cycle inventory method. According to the system expansion and substitution method, the environmental impacts of co-products were allocated among the main products of zinc, lead and sulfuric acid. The related impacts were assessed by use of Global Warming Potential （GWP） and Acidification Potential （ACP）. The results show that the GWP index from 1998 to 2000 is 11.53, 11.65, 10.93 tCO2-eq/tZn respectively, the ACP index decreases from 14.88 kgSO2-eq/tZn in 1998 to 10.99 kgSO2-eq/tZn in 2000. Power and electricity generation, followed by smelting and zinc distillation, are mainly responsible for GWP. Sintering individually affects ACP. Reduction in greenhouse gas emissions of the ISP may come from energy conservation measures rather than from technological developments. And recycling more secondary Pb and Zn materials effectively treated by ISP, and reducing the amount of primary metal are the main ways to put SO2 emission under control.

飞机碳纤维复合材料蒙皮激光除漆技术的研究进展

碳纤维复合材料是飞机蒙皮的重要材料,除漆是飞机碳纤维复合材料蒙皮再次涂装之前最为重要的工序。激光除漆具有高效、可控、分层、“绿色”的优势,有望成为飞机碳纤维复合材料蒙皮除漆的主要技术途径。介绍了激光分层可控除漆方法和机理,总结了激光能量密度、激光扫描速度、激光搭接率等工艺因素对飞机碳纤维复合材料蒙皮涂层去除的影响规律,提出了激光分层可控除漆工艺的优化思路,并归纳了激光除漆效果评价方法。列举了激光除漆技术在飞机复合材料表面涂层维修中的应用,并对飞机碳纤维复合材料蒙皮激光除漆技术的发展趋势进行了展望。

考虑极端天气冲击过程的风电机组竞争失效可靠性评估

针对风电机组的运行可靠性易受极端天气影响的问题,提出了一种考虑极端天气冲击过程的风电机组竞争失效可靠性评估方法。同时考虑风电机组自然退化、极端天气冲击导致的瞬时退化以及极端天气持续过程产生的加速退化,构建极端天气下的风电机组综合退化模型;考虑风电机组退化过程对其耐冲击性能的影响,建立风电机组竞争失效可靠度模型以评估风电机组可靠性;基于我国北方某风电场工程数据和极端天气历史数据评估了某2 MW风电机组的可靠性并进行了参数灵敏度分析。结果显示,到第5年时,仅考虑自然退化的方法评估风电机组可靠度为0.84,而考虑极端天气冲击过程的方法评估风电机组可靠度为0.178,后者更加符合工程实际。通过模型参数的灵敏度分析发现,运行时间超过3年后,退化失效开始逐渐影响风电机组的可靠性。

某迫榴炮击针疲劳寿命仿真与提升研究

击针大多采用细长及变截面结构,在循环撞击力作用下,易引起结构应力集中及交变应力,经常出现疲劳断裂故障,严重影响自动武器的可靠性,甚至威胁到作战人员安全。某迫榴炮击针在试验中偶发断裂现象,疲劳寿命约200发左右,为了提升该击针疲劳寿命,基于载荷传递过程,建立了击针在火药气体反冲力下高速运动与限位块的瞬态撞击模型,获取击针撞击过程交变应力,通过循环载荷作用下击针疲劳寿命评估,计算击针疲劳寿命与试验现象基本一致,验证了计算模型的准确性。在此基础上,开展了不同材料击针疲劳寿命提升研究,研究表明,将击针材料由PCrNi3Mo更换为30CrNi2MoVE后,击针疲劳寿命由215发提升到1670发,提升效果显著,改进后的击针经实弹射击试验验证在规定寿命周期内未发生断裂现象。

混凝土梁尾波信号环境噪声对照补偿法

为推进超声尾波技术在混凝土结构检测中的应用,研究了环境干扰引起的混凝土梁超声尾波信号特征噪声并提出噪声补偿方法。开展了自然环境下的混凝土梁超声试验,提出平移缩放旋转多特征算法,将尾波信号的波速、频率、幅值特征以时间平移、时轴缩放、向量旋转3种参数形式进行分析。通过两试件超声对照试验,对尾波环境噪声进行补偿,并与尾波干涉法信号降噪结果进行对比,验证本文方法的有效性。结果表明:温度是尾波环境噪声的主要来源,湿度为次要来源;本文方法对尾波信号的降噪效果可达到91%以上,显著优于尾波干涉法;通过对照试件特征参数的噪声补偿可达到90%水平。研究结果可为提高尾波信号稳定性提供研究方法与试验基础。

浇注温度与型壳温度对K4648镍基高温合金组织和性能的影响

针对某型号燃气涡轮导向器用K4648镍基高温合金室温冲击韧性无法达到标准要求(冲击韧性大于20 J·cm^(-2))的问题,在不同的浇注温度与型壳温度(1 490℃/1 050℃,1 490℃/950℃,1 460℃/1 050℃)下制备了K4648镍基高温合金,并进行了固溶+标准热处理,研究了浇注温度与型壳温度对合金显微组织和冲击性能的影响,获得了优化的工艺参数。结果表明:当型壳温度或浇注温度较低时,K4648镍基高温合金的晶粒尺寸和二次枝晶间距较小,块状初生α-Cr相含量较少、尺寸较小,合金的冲击韧性较大,冲击断口处次生裂纹数量较少;优化工艺参数为型壳温度950℃、浇注温度1 490℃,此工艺参数下制备的K4648镍基高温合金的冲击韧性最大,为21.4 J·cm^(-2),满足标准要求。

对冲式冲击试验机的设计及其动力特性的研究

为了对舰船内部电子设备进行高加速度冲击检测,提高冲击试验机的检测能力,对传统的冲击试验机进行了结构上的改进,提出了一种新型的对冲式冲击试验机,并对设计参数及其动力特性进行了研究。首先,介绍了对冲式冲击试验机的机械结构和控制原理,建立了设备的运动学模型,将试验动作划分成了四个过程(分别为蓄能、释放、碰撞与刹车阶段),并对各阶段进行了数学建模分析,确定了最大能量碰撞点;然后,建立了实体模型,使用ANSYS软件对其进行了计算机仿真,评估了结构稳定性,预测了其冲击加速度;最后,通过多次试验检测了动力特性,在不同位置下重复测试了该设备碰撞点位置与产生的冲击加速度大小,采集了加速度与位移信号,对信号进行了降噪滤波处理与微分计算,验证了设备性能的可靠性。研究结果表明:该试验机结构简单、操作容易,可重复试验;每次试验中碰撞点距理想位置分布数据散度在30 mm以内,数据稳定可靠,符合设计需求,控制方法合理;通过调节试验台与冲击台的释放位置可以改变冲击产生的加速度大小,在极限位置释放时最高能产生2 000 g左右的冲击加速度,满足各种元器件对耐冲击测试的试验要求。

基于台风过程的低矮建筑围护结构易损性分析

我国沿海台风多发地区的低矮建筑围护结构风灾损失值得关注。基于台风过程研究了低矮建筑围护结构在风致内外压、飞掷物冲击、结构抗力等多因素影响下的易损性。针对典型低矮建筑场景建立了飞掷物冲击概率模型,可以有效考虑风向、风速、建筑高度和间距,以及飞掷物起飞位置等实际因素。研究结果表明:低矮建筑围护结构的台风风灾易损性分析中有必要考虑台风过程,极值风速相似的台风也可能造成较大差别的建筑损伤极值;建筑损伤极值发生时刻一般滞后于极值风速时刻,损伤极值的持续时间与台风时长有关。研究中建立的飞掷物冲击概率模型相较于传统模型对我国沿海地区典型低矮建筑场景更为适用。

论过程性行政行为不可诉规则之突破——以出口退税疑而缓退为切入点

税务机关在办理出口退税业务中如果发现纳税人有骗税嫌疑,则将开展疑点调查、暂缓出口退税。在实务中,税务疑点调查并无时限要求,导致税务机关可以无限期调查,形成事实上的疑而不退,而法院也大多以该疑而缓退行为属于过程性行政行为而认定其不具有可诉性,造成纳税人无以救济的诉权困局。为了实质性化解疑而缓退的可诉性争议,宜针对“过程性行为”与“不产生实际影响的行政行为”的狭隘理解,将疑而缓退界定为“复合型过程性行为”,并对“实际影响”作出“权益增减变动型”与“权益限制型”的二元划分,并通过建构法定的暂缓退税时限制度,对税务机关施加法定时限这一程序限制,用以保障“权益限制型的复合型过程性行为”下纳税人在事实上的出口退税利益。

注塑条件对抗冲聚丙烯力学性能影响研究

不同的注塑工艺条件会影响聚丙烯微观结构及力学性能,主要研究了注射速率(v)、注射压力(P_(1))、保压压力(P_(2))、保压时间(t)和熔体温度(T)五个参数对高流动抗冲共聚聚丙烯SP531冲击强度和弯曲模量的影响,并分析了注塑条件与力学性能的关系,结果表明:对于高流动SP531,最佳的注塑条件为注射速率30%,注射压力2 MPa,保压压力4 MPa,保压时间40 s,熔体温度200℃。

基于数据影响的业务流程一致性检查方法

近年来,业务流程的精确管理受到越来越多的关注,作为业务流程管理内容之一的一致性检查技术正变得越来越重要。现有的一致性检查技术主要从模型的控制流角度出发,并未考虑业务流程中的数据或数据的变化对业务流程产生的影响,为此提出了一种基于数据影响的业务流程一致性检查方法。首先,通过业务流程建模符号(business process modeling notation,BPMN)模型中数据和行为之间的依赖关系来分析数据对偏差活动预期行为的影响,进而获取偏差活动的预期行为集;其次,通过在BPMN模型中引入决策模型和符号(decision model and notation,DMN)决策表来充分捕获当前实例执行的数据上下文与行为上下文之间的关系,以区分有效数据更改和异常数据更改,找到偏差活动的有效预期行为集。最后,通过设计数据对偏差活动影响的各类成本函数提出了有效一致性检查方法。实验结果表明,相比已有工作,该方法在进行业务流程一致性检查时提高了业务流程的一致性,可以成功捕获偏差活动作出反应的适应行为,使得业务流程在复杂多变的环境下表现得更加准确、合理。