Li_2S─B_2O_3（─LiBr）玻璃的结构表征

用ＮＭＲ和ＸＰＳ技术研究了Ｌｉ２Ｓ─Ｂ２Ｏ３（─ＬｉＢｒ）体系硫氧化物玻璃的结构，结果指出，４─配位硼分数Ｎ４仅仅由玻璃Ｌｉ２Ｓ／Ｂ２Ｏ３摩尔比决定．而与ＬｉＢｒ含量无关，这表明Ｌｉ２Ｓ作为变形剂参与了玻璃网络形成，而ＬｉＢｒ仅作为参杂剂溶解于玻璃基体中，并进入网络间隙。含ＬｉＢｒ玻璃７ＬｉＮＭＲ谱运动变窄说明Ｌｉ＋离子是移迁离子．Ｓ２ｐ的ＸＰＳ解析谱证实了玻璃中桥硫和非桥硫的存在．Ｌｉｌｓ结合能值显示出Ｌｉ＋离了迁移的化学环境。     

基于IPA法的传统型景区游客满意度评价——以琅琊山景区为例

游客满意度评价对景区规划、建设和管理很重要。结合文献分析与德尔菲法,构建了传统型景区游客满意度评价指标体系,并以琅琊山景区为例采用IPA模型进行案例分析。结果表明:琅琊山景区7个要素测度层——资源特色、景区环境、景区产品、景区交通、景区服务、景区设施、景区价格及30项因子测度指标感知均值都为满意度重要性,游后感知实绩(满意度)全低于游前期望(重要性);IPA矩阵分析30项因子分布为:优势区域6项、修补区域4项、机会区域15项、维持区域5项,游后满意度(实绩)与游前重要性(期望)感知评价"双高项"占20.0%,"双低项"占50.0%。总体上游客期望值较高而满意度不高,各评价因子的满意度评价差异较大,景区需提升产品与服务。     

鄂尔多斯盆地南部延长组富铀凝灰岩地球化学特征及形成机制

本文系统地研究了鄂尔多斯盆地南部延长组凝灰岩元素和同位素地球化学特征。结果表明：凝灰岩主量元素具有高K、高Al、Si中等至高、低Na的特征; REE总体特征为轻稀土富集、重稀土亏损,∑REE在4857～40212 μg/g 之间变化,Eu呈现出负异常,在034～082内变化,δCe范围在080～208之间; 微量元素中U含量在312～144 μg/g 之间,Ba、U、Th、Hf和Ce呈明显正异常,Nb、P、Ti和Rb呈现负异常。详细的分析表明：U的富集和一些微量元素如Ta、Dy、Lu等相关,Th与∑REE存在明显的正相关性,这些变化可能和盆地中铀矿的富集有关; 凝灰岩的硫同位素总体呈现深源特征。根据以上的研究对凝灰岩的形成原因及形成环境进行了探讨。鄂尔多斯盆地南部延长组凝灰岩来源于秦岭造山带火山作用,其中的铀元素富集是由于砂岩型铀矿中铀向凝灰岩迁移而被还原所致。本研究对盆地砂岩型铀矿的铀运移和富集机理认识具有一定指导意义。     

石笋记录的西南地区MIS4阶段夏季风的演化

基于重庆市丰都县羊子洞石笋Y-02的12个²³⁰Th年龄和503个氧同位素数据重建了中国西南地区60~73ka B.P.时段夏季风的演化历史。Y-02的δ¹⁸O记录显示中国季风区D/O18、D/O19a和D/O19共3个千年尺度夏季风增强事件与格陵兰间冰阶（GIS）18~19相对应。此外,Y-02记录显示：紧接着D/O18事件以后,夏季风强度突然减弱,而此时北半球高纬度地区正经历着明显的降温过程。Y-02记录捕捉到的这次东亚夏季风突然且短暂的一次减弱过程,可能是H6事件或者是H6事件季风最弱的时段。Y-02的δ¹⁸O记录显示,D/O18事件是一次较强烈的千年尺度季风增强事件,持续时间近千年,而D/O19事件在持续时间和强度上不如D/O18事件,这不同于格陵兰冰芯记录。中国季风区气候变化与格陵兰地区存在着如此紧密的联系进一步支持：东亚夏季风演化受到北半球高纬度地区气候变化的影响,但是对具体的气候事件响应可能存在不同的模式。

     

生物基可降解聚乳酸(PLA)沙障对沙丘表层沉积物粒度特征的影响

以吉兰泰盐湖北部流沙区铺设8 a的不同规格聚乳酸（PLA）沙障内沉积物为研究对象,利用激光衍射技术分析了沙丘表层0~3 cm沉积物粒度组成,计算并分析平均粒径、标准偏差等粒度参数,探讨了影响障内沉积物相对粗细的关键组分,分析PLA沙障的防沙效益。结果表明：PLA沙障内沉积物以细沙、中沙、极细沙为主。中沙、极细沙、细沙是障内沉积物的关键组分。PLA沙障的阻滞作用使得中沙、粗沙含量百分比升高,细颗粒含量百分比降低,障内沙粒分选性逐渐变差,峰态偏离正态分布,向负偏方向发展,频率分布曲线分布范围变宽,累积频率曲线变缓,表层颗粒组成趋于粗化。1 m×1 m规格PLA沙障内均以积沙为主;沙丘迎风坡和背风坡的2 m×2 m、3 m×3 m沙障内均为积沙状态,丘顶则为风蚀状态。综合考虑沙障铺设成本和防护效果,得出研究区域内2 m×2 m规格PLA沙障整体防沙效益最佳。     

基于土地集约利用的长株潭城市群建设用地供需仿真模拟

土地集约利用反映了土地利用的综合状态,是协调土地供需平衡的重要指标。运用系统动力学（SD）构建城市建设用地供需反馈关系回路以及指标变量函数,在此基础上,建立长株潭城市群建设用地供需系统模型,仿真模拟低土地集约利用度、中等土地集约利用度、高土地集约利用度三种不同状态条件下,2016-2030年区域的建设用地、工业用地和居住用地供需变化趋势。结果表明：① 研究区用地规模仍处于扩张状态,城市建设用地数量增长速度总体较快。但三种发展状态下用地增长规模、速度存有差异;② 在低集约度模式下,建设用地规模及供地数量大,易造成土地资源的浪费;高集约度模式下,建设用地供给紧缩,用地规模增长缓慢,总规模偏小,不利于城镇化的良性发展;中等集约度模式则在用地规模和供给量上均与社会经济发展相适应,能体现现代城市发展理念;③ 工业用地占建设用地比例保持在15%~21%之间,其中低集约度模式下比例逐年上升,中等和高集约度模式下呈缓慢下降并趋于稳定之势;居住用地占建设用地的比例维持在27%~35%之间,其中低集约度和中等集约度模式用地占比呈下降趋势,高集约度模式比例总体维持在较高水平。研究通过对三种发展模式的设定,确定了不同指标在三种模式下的变化趋势,可为土地供需决策优化、城市建设规划及土地供给侧结构性改革提供科学参考。     

Analysis of city centrality based on entropy weight TOPSIS and population mobility: A case study of cities in the Yangtze River Economic Belt

Based on statistical data and population flow data for 2016,and using entropy weight TOPSIS and the obstacle degree model,the centrality of cities in the Yangtze River Economic Belt(YREB)together with the factors influencing centrality were measured.In addition,data for the population flow were used to analyze the relationships between cities and to verify centrality.The results showed that:(1)The pattern of centrality conforms closely to the pole-axis theory and the central geography theory.Two axes,corresponding to the Yangtze River and the Shanghai-Kunming railway line,interconnect cities of different classes.On the whole,the downstream cities have higher centrality,well-defined gradients and better development of city infrastructure compared with cities in the middle and upper reaches.(2)The economic scale and size of the population play a fundamental role in the centrality of cities,and other factors reflect differences due to different city classes.For most of the coastal cities or the capital cities in the central and western regions,factors that require long-term development such as industrial facilities,consumption,research and education provide the main competitive advantages.For cities that are lagging behind in development,transportation facilities,construction of infrastructure and fixed asset investment have become the main methods to achieve development and enhance competitiveness.(3)The mobility of city populations has a significant correlation with the centrality score,the correlation coefficients for the relationships between population mobility and centrality are all greater than 0.86(P<0.01).The population flow is mainly between high-class cities,or high-class and low-class cities,reflecting the high centrality and huge radiating effects of high-class cities.Furthermore,the cities in the YREB are closely linked to Guangdong and Beijing,reflecting the dominant economic status of Guangdong with its geographical proximity to the YREB and Beijing's enormous influence as the national political and cultural center,respectively.     

Millennial-scale evolution of Hunshandake Desert and climate change during the Holocene in Inner Mongolia,northern China

The Hunshandake Desert is located at the northern edge of the East Asian monsoon region,and its natural environment is sensitive to monsoonal changes.Geologic records suggest that desert evolution corresponding to climate change had experienced several cycles in the Holocene,and the evolutionary process can be distinguished by four dominant stages according to changing trends of the environment and climate.(1) Holocene Ameliorative Period(11.0-8.7 cal ka B.P.),when the desert area gradually shrank following an approaching warm-wet climate and strengthening summer monsoon.(2) Holocene Optimum(8.7-6.0 cal ka B.P.),when the majority of moving sand dunes were stabilized and vegetation coverage quickly expanded in a suitable warm-wet climate and a strong summer monsoon.(3) Holocene Multivariate Period(6.0-3.5 cal ka B.P.),during a low-amplitude desert transformed between moving and stabilized types under alternating functions of cold-dry with warm-wet climate,and winter monsoon with summer monsoon.(4) Holocene Decay Period(since 3.5 cal ka B.P.),when the desert area tended to expand along with a weakened summer monsoon and a dry climate.     

干涸尾闾湖盆区泥漠地表磨蚀释尘特征

沙粒的表面磨蚀效应是地表产尘、释尘的重要机制,针对干湖盆泥漠地表开展磨蚀释尘实验研究,对理解干湖盆地表风蚀过程及盐碱尘暴形成机理具有重要意义。对采自西居延海干涸湖盆泥漠地表土样进行室内磨蚀模拟实验,研究了不同粒级（细、中、粗）沙粒不同落沙角度（30°,45°,60°）的磨蚀效应。结果表明：（1）泥漠地表磨蚀实验中能够产生明显释尘效应的沙粒粒级阈值为中沙（0.25 mm<M_d<0.50 mm）;（2）磨蚀粒径粒级相同时,磨蚀角度会对泥漠地表磨蚀释尘速率产生影响,磨蚀量的角度排序为60°>30°>45°,但同一粒级3种角度下的磨蚀释尘率差异不显著。（3）磨蚀角度为45°时,计算了泥漠地表的质量磨蚀率与能量磨蚀率,其中中沙为0.04 g·kg^-1、0.43 g·J^-1,粗沙为0.08 g·kg^-1、0.74 g·J^-1,极粗沙为0.26 g·kg^-1、2.54 g·J^-1;在磨蚀沙粒粒级倍增而磨蚀角度不变情况下,泥漠地表磨蚀释尘率与能量磨蚀率未发生正比例线性增长变化。