干旱半干旱区农田土壤风蚀特征及参数化研究进展

干旱半干旱地区是中国的农业后备战略基地,然而近年来该地区农田土壤风蚀现象严重,沙/尘释放量显著增大,威胁农业的可持续发展和生态系统平衡。目前绝大部分的天气和气候模式仅考虑了沙漠地表起沙,忽视退化农田的土壤风蚀起沙,导致起沙通量模拟存在很大的不确定性。对20世纪50年代以来干旱半干旱区农田土壤风蚀起沙特征及参数化做了详细的分析总结,回顾并梳理了干旱半干旱区农田土壤风蚀观测和数值模拟的研究脉络以及存在的问题,为提高农田起沙的模拟精度提供了有效参考,对中国干旱半干旱区农田土壤风蚀防治、土地荒漠化治理以及理解未来土地利用改变对大气污染的影响具有重要意义。     

Influencing factors for catalytic oxidation of mine gas to methanol in liquid phase

The influencing factors for liquid phase catalytic oxidation of mine gas to methanol （in form of CHaCOOCH3） are studied using the self-established experimental apparatus. The results show that CH3COOCH3 （target product） is obtained by using CH3COOH as reaction solvent, and the yield of target product increases with the increasing of reaction temperature, gas pressure and reaction time. In the mine gas-Pd（OAc）2-CHaCOOH system, the yield of CHaCOOCH3 increases with the increasing of addition of Pd（OAc）2 which is redox catalyst for mine gas conversion. The yield of CH3COOCH3 will be greatly improved by composite additional oxidant which is obtained by equimolar mix of p-benzoquinone with NO2.     

硅酸盐熔体和流体中金的性质及行为研究进展

岩浆演化过程中岩浆—流体阶段发生的相转变过程控制了元素在两相之间的分配行为。作为与岩浆热液活动有密切成因联系的金矿床,其在硅酸盐熔体和流体中的性状及两相间的分配行为是控制该类矿床成矿的重要物理化学因素。介绍了金在流体、熔体中的性状,论述了其在流体/硅酸盐熔体间的分配行为不仅受温度、压力、氧逸度等物理化学条件的影响,还受流体组分(阴离子、阳离子)、熔体组成(Na2O+K2O/Al2O3,Na/K,SiO2,NBO/T)的制约;最后对目前实验研究存在的问题、改进方法以及今后的研究方向进行了探讨。     

Assessment of groundwater changing trends through the generalized large well method with confined–unconfined flow model in open-pit mine area

In this paper, a simple but accurate method (generalized large well method) is presented to assess groundwater level trends during mine exploitation. This method includes a mathematical model of confined–unconfined well flow and a corresponding analytical solution. Based on the method, a case study was analyzed with data from the Yimin open-pit mine. As a result, the radius of groundwater level rose, along with the increase of the exploitation intensity. Moreover, a suitable value of pumping flow could be beneficial to understanding potential groundwater contamination concerns. Additionally, it has also been predicted that the groundwater level of the Yimin open-pit mine will change within the next 3 years. The Yimin open-pit mine case study demonstrates the validity of the analytical method explained herein. The presented methodology provides a theoretical foundation for assessment of groundwater changing trends in other open-pit mines with similar hydrogeological conditions.     

华南陆块陆内成矿作用的一些科学问题

华南陆块由扬子地块和华夏地块组成,是全球罕见的世界级多金属成矿省,成矿潜力巨大。华南陆块的形成和演化,受到了很有特色的陆内大陆动力学过程的影响,其中的晚古生代地幔柱成矿系统、中生代大面积低温成矿系统、中生代大花岗岩省成矿系统等陆内成矿系统,在全球背景中很有特色,是全球研究陆内成矿作用的理想基地。对华南陆块地质历史时期的大陆动力学过程如何制约上述成矿作用的发生,以往已开展不同程度的研究并取得重要成果。笔者在论述这些研究进展的基础上,提出了三大成矿系统需要进一步研究的一些科学问题。     

光学综合孔径干涉成像的关键技术及多光束干涉仿真

闭合相位技术、U -V覆盖技术和像重构技术是光学综合孔径干涉成像的三个关键技术。文中简要介绍了光学综合孔径技术的发展历史、这三种关键技术和光学综合孔径望远镜阵的构成 ,对之进行了多光束干涉的计算机仿真和实验仿真 ,两者结果一致说明了光学综合孔径干涉成像技术中有关干涉的理论的正确性 ,指出了下一步的研究方向。     

论企业家的竞争意识

企业家的竞争意识是企业能否取得竞争胜利的基本条件之一。从思维方式、心理品质、竞争观念等三个方面就企业家应具备什么样的意识方可应对市场竞争并取得胜利进行探讨 ,以求让企业家们为更好地应对竞争挑战而自觉地培养良好的竞争意识提供帮助。     

江西省高速公路气象服务效益评估及气象灾害影响分析

基于江西省气象服务中心开展的有关高速公路气象服务问卷调查,分析了江西省高速公路气象服务的现状、敏感性、气象服务需求和满意度,在此基础上对江西省高速公路气象服务效益进行评估,并分析了高速公路主要的致灾气象因子。结果表明:1)高速公路对气象条件有很强的敏感性,高速公路安全对灾害预警、短期天气、重大节假日天气表现最为敏感;高速公路行业对目前的高速公路气象服务总体满意。2)江西省高速公路应用气象信息产品产生的年综合增值占本行业年产值的比率为2.25%—3.15%,且2009—2013年高速公路气象服务效益逐年递增。3)低能见度、路面结冰、路面湿滑是高速公路的主要致灾气象因子;利用相关气象资料和高速公路灾害数据,确定低能见度和路面结冰、降雨等高速公路致灾气象因子临界值,对高速公路行业的气象防灾减灾具有一定的指导意义。     

Scalar Flux–Gradient Relationships Under Unstable Conditions over Water in Coastal Regions

The scalar flux–gradient relationships of temperature ( $\phi _{T}$ ? T ) and specific humidity ( $\phi _{q}$ ? q ) under unstable conditions are investigated using eddy-covariance measurements of air–sea turbulent fluxes and vertical profiles of temperature and specific humidity collected from a marine meteorological platform. The gradients of temperature and specific humidity are obtained from measurements at five heights above the sea surface using the log-square fitting method and the simpler first-order approximation method. The two methods yield similar results. The proposed flux–gradient relationships $\phi _{T}$ ? T and $\phi _{q}$ ? q covers a wide range of instability: the stability parameter $\zeta $ ζ ranges from $-$ ? 0.1 to $-$ ? 50. The functional form of the proposed flux–gradient relationships is an interpolation between the Businger–Dyer relation and the free convection relation, which includes the “ $-$ ? 1/2” and “ $-$ ? 1/3” scaling laws at two different stability regimes. The widely used COARE 3.0 algorithm, which is an interpolation between the integrals of the Businger–Dyer and the free convection relations, is also evaluated and compared. The analysis and comparisons show that both schemes generate reasonable values of $\phi _{q}$ ? q in the whole unstable regime. The COARE 3.0 algorithm, however, overestimates $\phi _{T}$ ? T values under very unstable conditions. The errors in the flux–gradient relationships induced by the random errors in the turbulence measurements are assessed. When the random errors are taken into account, the observations agree with predictions of various schemes fairly well, implying that the dominant transport mechanism is adequately captured by the Monin–Obukhov similarity theory. The study also shows that $\phi _{q}$ ? q is significantly ${>}\phi _{T}$ > ? T under unstable conditions and that the ratio $\phi _{q}/\phi _{T}$ ? q / ? T increases with $-\zeta $ ? ζ . The ratio of $\phi _{q}$ ? q to $\phi _{T}$ ? T and the ratio of turbulent transport efficiencies of heat and water vapour ( $R_{wT}/R_{wq}$ R wT / R wq ) suggest that heat is transported more efficiently than water vapour under unstable conditions.     

Correlation of karst agricultural geo-environment with non-karst agricultural geo-environment with respect to nutritive elements in Guizhou

The karst area accounts for 61.9% of the total area in Guizhou Province, which gives rise to a fragile environment and backward economy. Comparative studies on the element contents of rock and soil and agriculture production in both carbonate area and non-carbonate area have been made to establish factors leading to low output and poor quality of agricultural products in the karst area. The result shows that there is an apparent lack of nutrient elements in carbonate rocks. The trace element contents of carbonate rocks are only 3532.27×10-6, but those of non-carbonate rocks are 10894.21×10-6. The available element contents in culti-vated soil delivered from carbonate rocks are merely 101.4×10-6, but those from non-carbonate rocks are 326.05×10-6. The available element contents and total element contents in cultivated soil delivered from non-carbonate rocks are 3 times higher than those from carbonate rocks. Besides, high-quality agricultural products such as rice, potato and tea are mainly produced in the non-carbonate area. It is indicated that the low output and quality of agricultural products are caused by the above-mentioned low trace element contents and poor agricultural environment. Therefore, a new method of mineral nutrients compensation has been put forward, which is very effective to raise the load-bearing capacity of agricultural environment, agricultural output and quality of agricultural products.