西安市降尘粒度空间分布特征及环境意义

笔者在西安市区11个取样点进行了为期1a连续采样，采集样品14件。结果证明，降尘可以分为大小明显的两群，小于10μm的颗粒物以工业污染的产物为主，较大颗粒主要为自然源沙尘。西安市降尘粒度明显偏小，其中≤50μm的颗粒占总量的80％～98％；≤10μm的颗粒占30％～60％；≤2．5μm的颗粒占≤10μm颗粒的20％～46％。受城市风动力条件控制，沿东北—西南方向降尘平均粒径依次降低；降尘粒度分选性与小于10μm粒级颗粒的含量负相关，相关系数为-0．9212，负相关性明显。颗粒平均粒径和粒度分选性可以作为当地空气质量的综合性标志。     

合徐高速北段膨胀土的物质组分及微结构研究

文章以X射线衍射为主,并结合化学全分析、偏光显微镜、扫描电镜对合徐高速北段沿线经过的蚌埠、怀远和宿州地区的膨胀土进行矿物化学成分以及微结构特征研究,探明膨胀土的液限、塑性指数以及胀缩性与其矿物组分、阳离子交换容量、氧化度及微观结构之间的关系,并对其微结构进行分类。研究表明:膨胀土在其蒙脱石含量基本相等的情况下,伊利石含量的多寡对膨胀土工程性质的控制影响十分明显,而膨胀土的氧化程度则是控制膨胀土工程特性的另一个重要因素。     

陕北地区水土流失原因及其治理方法

探讨陕北地区水土流失的原因，研究其改善与治理措施．陕北地区形成水土流失的原因主要是当地植被的破坏以及降雨量和蒸发量的不均衡，使得植被难于生长恢复．提出了采用以小流域治理为起点，应用农用纺织品的力学特性和水力学特性发挥其物理固沙保土和吸湿保水特性培育永久的生态植被，由点带面直至全面治理水土流失的方案．     

皖北地区砂姜黑土低产原因及其综合治理

砂姜黑土是皖北地区一种重要的耕作土壤．本文分析了砂姜黑土的低产原因和增产潜力，并对砂姜黑土的治理措施与开发途径进行了深入探讨．     

南华北上二叠统石千峰组物源与沉积环境分析

目的为恢复华北南部地区石千峰组原盆地沉积环境格局,为进一步研究华北南部地区二叠系沉积地质与盆地原型提供支持。方法根据岩石碎屑组分基本数据,运用地层厚度、砂岩百分含量、古水流、砂岩成分的系统分析方法。结果研究区地层自南西向北东呈现依次增厚的趋势,整体为北东方向倾斜的宽缓斜坡环境;砂岩分布特征指示物源来自南部隆起区和沉积中心在研究区以北地区。结论华北南部地区石千峰组整体属于近山的海陆过渡相陆缘近海湖环境内的充填物,沉积物质主要来源于南部的秦岭古隆起,并向晚二叠世华北盆地南部提供了大量的陆源碎屑物质。     

Sea surface temperature record from the north of the East China Sea since late Holocene

Using the alkenone paleotemperature index U37^k, a high-resolution sea surface temperature （SST） record since 3600 a BP was reconstructed from the mud area in the north of the East China Sea. Combining with the grain size distribution curve of sensitive grain size group, which may reflect the East Asia Winter Monsoon activity, the palaeoenvironmental evolution cycle throughout the late Holocene in the area was obtained. The marine environment evolution during the last 3600 years displays a five-stage trend. （1） Temperature descending period from 0.85 cal. ka BP to present. The maximum temperature decrease amplitude is 2℃. The winter monsoon intensified and ＇Little Ice Age＇ were recorded in this period. （2） Warming period from 1.90 to 0.85 cal. ka BP. The mean temperature increase amplitude is 0.8℃. The Sui-Tang warming period was recorded at about 0.85--1.35 cal. ka BP and a prominent cooling event was recorded at 1.4 cal. ka BP in this period. （3） Temperature descending period from 2.55 to 1.90 cal. ka BP. Temperature cooling amplitude is 0.9℃. This period is coincident with an integrated temperature circle recorded in the Antarctic ice core, with the temperature changes from a slow cooling stage to a rapid warming stage. （4） Temperature comparatively stable with a little ascending period from 3.2 to 2.55 cal. ka BP. Temperature warming amplitude is 0.3℃. This period is coincident with the temperature fluctuant ascending period recorded in Antarctic ice core. （5） Temperature comparatively stable with little descending period from 3.6 to 3.2 cal. ka BP. This period corresponds with the temperature fluctuant cooling period recorded in Antarctic ice core. Basically, those five periods were coincident with the Antarctic ice core record. During the global cooling stage, the SST change in the continental shelf sea can be adjusted simultaneously.     

Lawsonite-bearing eclogites in the north Qilian and north Altyn Tagh： Evidence for cold subduction of oceanic crust

Laboratory experiments and thermal models predic that lawsonite-bearing eclogite should be the dominan rock types for typical oceanic subduction zone[1,2] However, eclogite containing unaltered lawsonite is rare in nature and has been described only from …     

贵阳市建筑灰尘重金属粒径效应及健康风险评估

以贵阳市4个建筑工地9个区域的建筑灰尘为研究对象,分析不分粒径混合样品中Cu、Pb、Zn的总量,并对3种重金属含量的粒径分布及其中、细颗粒灰尘重金属健康风险进行评估。实验结果表明:贵阳市建筑灰尘中Cu、Pb、Zn含量的变化范围较大,存在不同程度污染,其中Zn为超过背景值倍数最高的重金属。3种重金属的富集存在空间差异,Cu的较大值出现在建筑区旁道路、建筑区门口、金属堆放区,Pb的较大值出现在建筑区门口、建筑区内道路、建筑区旁道路,Zn的较大值出现在楼内、楼梯、建筑区门口、建筑区内道路、金属堆放区。不同重金属的粒径分布差异较大,细颗粒是主要的污染粒径区间。中、细颗粒重金属含量存在显著空间差异,与重金属全量空间分布基本一致。3种重金属在各区域都表现出细颗粒富集最大,均超过40%,粗颗粒富集最小。手-口摄入途径是人群对中、细颗粒建筑灰尘Cu、Pb、Zn暴露的主要途径。儿童非致癌风险高于成人,但3种重金属对人群非致癌风险均小于阈值1;对人群不造成健康危害。建筑灰尘重金属非致癌风险对不同人群在空间上差异较大,建筑区内道路、建筑区旁道路、建筑区门口灰尘对儿童的叠加风险指数接近1,潜在危险不容忽视;成人在各区域的叠加风险指数均未超过0.1,未表现出突出的健康风险。     

皖北奥陶系古岩溶分期分类及岩溶岩特征

研究表明,皖北奥陶系古岩溶可划分为沉积岩溶作用期、风化壳岩溶作用期、埋藏岩溶作用期、构造岩溶作用期和二次埋藏岩溶作用期;其岩溶类型主要有沉积岩溶、风化壳岩溶、埋藏岩溶或压释水岩溶和构造岩溶或热水岩溶四种类型;其岩溶岩包括岩溶沉积岩和岩溶改造岩两个大类,并可进一步划分出8个亚类和5个子亚类.     

兰州市冬季大气沉降尘粒度特征及来源解析

通过对兰州市冬季大气沉降尘颗粒的粒度分布特征及参数的分析,认识其可能来源及对环境的影响．从实验结果发现兰州市大气沉降尘粒径主要为10-50μm,各个采样点的PM2．5和PM10贡献突出,说明兰州市颗粒物污染严重．研究表明兰州市大气中可吸入颗粒物的来源主要为生活燃煤和汽车、工厂产生的废气;粒径〈50μm的颗粒物主要来源于空气搬运作用迁移而来的黄土粉尘等;粒径〉50μm的颗粒物主要是由人为引入或由特大尘暴使大颗粒物近源搬运的结果．不同的功能区中,工业区内污染最大,其次为生活区和其他区．从整体看兰州市的4个行政区内大气沉降尘粒度特征有较大的相似性,除了受生活、汽车、工业以及黄土高原的影响外,兰州城市整体布局存在较大缺陷,工业区和生活区混杂、密集。布局不合理．     

矿井粉尘运移规律性的试验研究

对矿井粉尘运移规律性进行了较系统的测定与研究.采用滤膜称重法测定粉尘浓度;样品经过液相分散法处理后,采用显微镜观察法测定粉尘的分散度,并利用数码相机和图像处理软件对计数工作进行改进.通过对测定的数据进行分析和归纳,得出了巷道沿程及断面上的粉尘浓度及分散度的分布规律.     

阴山北麓春季土壤含盐量及其与电导率的关系研究

对阴山北麓春季土壤野外采样的含盐量进行室内理化分析表明,土壤已接近或达到盐渍化水平.在所采集的土壤样品中,中度盐渍化土壤、轻度盐渍化土壤及非盐渍化土壤所占比重分别为7.7%、53.8%和38.5%.对土壤浸提液电导率的测定表明,土壤含盐量与电导率呈较显著的线性相关关系.根据该区的实际情况,提出植树种草、井灌沟排、施用磷石膏、合理开发利用土地等措施,以改良土壤.     

Micromorphology and physicochemical properties of hydrophobic blasting dust in iron mines

The micromorphology and physicochemical properties of hydrophobic blasting dust(HBD)from an iron mine were comprehensively analyzed by laser particle size analysis(LPSA),scanning electron microscopy(SEM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).The results show that the HBD particles can be classified into three types based on their particle size(PS):larger particles(PS>10μm),medium particles(1μm≤PS≤10μm),and nanoparticles(PS<1μm).The cumulative volume of respirable dust(PS≤10μm)was 84.45%.In addition,three shapes of HBD were observed by SEM:prism,flake,and bulk.In particular,the small particles were mostly flaky,with a greater possibility of being inhaled.Furthermore,the body and surface chemical compounds of HBD were determined by XRD and XPS,respectively.Ammonium adipate(C6H16N2O4)was the only organic compound in the body of HBD,but its mass fraction was only 13.4%.However,the content of organic C on the surface of HBD was 85.35%.This study demonstrated that the small-particle size and large amount of organic matter on the surface of HBD are the main reasons for its hydrophobicity,which can provide important guidance for controlling respirable dust in iron mines.     

地球物理综合勘探技术在南水北调工程中的应用

南水北调西线一期工程的引水隧洞长达73km，最大埋深1100m，因此软围岩大变形及岩爆等工程地质问题尤为突出。利用地球物理综合探测技术对工程区的工程地质条件进行了研究，并对隧洞开挖过程中可能遇到的工程地质问题进行了分区。对于南水北调西线工程而言，首先应该考虑的地球探测指标是探测深度。因可控源音频大地电磁法（CSAMT法）探测深度为1～2km，所以当各种地球物理探测技术对深部的探测结果相互抵触时，要对CSAMT法的测试结果给予充分的重视。在南水北调西线一期工程玛柯河-贾曲段的工程地质条件勘察过程中，地球物理综合勘探技术对155～239桩段断层破碎带的解释结果与野外岩石露头所反映的地质信息吻合较好，并得到了钻孔资料的验证，说明地球物理综合勘探技术值得在南水北调西线工程中推广。     

北美海棠6品种在南方地区的引种研究

【目的】探索北美海棠在南方地区的适应性和观赏性,为有效引种和培育新品种提供理论依据。【方法】以6个新优北美海棠品种(‘黛玉’、‘白兰地’、‘丰盛’、‘王族’、‘草莓果冻’和‘紫宝石’)为引种试材,在南方地区进行物候期、观赏性及耐热性观测和试验。【结果】6个北美海棠品种均能正常萌芽、展叶、开花、结果,且具有较高的观赏价值。夏季生长适应性观测显示,6个品种在南方高温环境下叶片出现不同程度的皱缩、卷曲、叶缘枯焦等变化。生理适应性表明,各品种均能通过自身质膜热稳定性、抗氧化系统及渗透调节方式应对南方夏季高温环境。【结论】6种北美海棠在南方地区夏季高温环境下生长受到一定影响,但通过自身的生理调节,能正常完成生活史,且表现出较高的观赏价值。引种的6种北美海棠表现最好的为‘黛玉’,其次是‘白兰地’和‘紫宝石’。南方地区可根据需要在苗木生产和景观绿化中选择适宜的北美海棠品种栽培。     

Determination of erodible particles on cultivated soils by wind tunnel simulation

The erodible particle size distribution, diameter range and separate content of three soils from semi-arid regions of China were determined at different wind velocities through wind tunnel simulation and dry sieving. It was demonstrated that soil erodibility by wind depends not only on the intrinsic soil properties, but also on the extrinsic erosion effect of the erosive winds. It was supposed that there existed general consistency in the mechanics of wind erosion on different soils.     

Compound-specific carbon isotope compositions of individual long-chain n-alkanes in severe Asian dust episodes in the North China coast in 2002

Asian dust storms originating from the arid regions of central and eastern Asia and from the Loess Plateau in China frequently occur in spring [1,2]. Driven by the East Asian monsoon, Asian dust can be transported to northern Pacific Ocean[2―8]. Asian du…     

Synthesis of CNT film on the surface of micro-pyramid array and its intense pulsed emission characteristics

We developed a new scheme to suppress the electric-field-screening effect in high growth density of a carbon nanotube(CNT) film during its intense pulsed emission.We synthesize the CNT film on a tridimensional surface(t-CNT film).The tridimensional surface includes wet etched silicon pyramids,and the Ni layer is electroless plated thereon.The intense pulsed emission characteristics of the t-CNT and planar-grown CNT(p-CNT) films were measured using a diode structure in single-pulse mode.The even turn-on field decreased from 5.5 V/μm for p-CNTs to 2.8 V/m for t-CNTs,and the peak emission current increased from 232 A for p-CNTs to 324 A for t-CNTs at a peak field intensity ～12.2 V/m.The peak current of the t-CNT film increased by ～39.7% over the p-CNT film.It is clear that the micro-pyramid array can effectively suppress the field screening effect to improve the electron-emission of CNT films.     

中国碳排放特征及碳汇经济建设分析

介绍了碳汇经济的概念,综述了中国碳排放的特征,并就进行碳汇经济建设开展讨论,这对于理解我国碳排放变化与经济发展之间的内在联系,以及产业发展调整具有一定的意义。     

皖北新元古代刘老碑组滑塌沉积及其地质意义

安徽北部淮南、凤阳地区刘老碑组为一套页岩、钙质泥岩和泥灰岩沉积,厚度685～857m,中上部发育Chuaria化石群。刘老碑组中段发育一套滑塌沉积。滑塌沉积1～3层,单层厚30～200cm,由粉砂质泥岩、钙质泥岩、泥质粉晶灰岩及含石英粉砂粉晶灰岩组成。滑塌沉积中褶皱发育,有平卧不对称褶皱、旋转滑塌等。滑塌褶皱轴面产状表明,存在一个走向近EW,向SE154°±倾斜的大陆边缘斜坡。并且推测发育Chuaria化石群的刘老碑组中段页岩可能形成于水体较深的大陆边缘环境。