Comparative study on the “optic-electric” monitoring method for the deformation and failure of surrounding rock in stopes

Natural Hazards - The evolution law for the mining-induced deformation and failure of surrounding rock is an important parameter for coal mine work safety. Accurate detection is a scientific matter...     

西部贫困山区的产业开发与项目选择--以贵州省紫云自治县为例

紫云自治县为全国重点扶持的特困县之一,21世纪来临之际贫困率仍高达26%,脱贫任务十分艰巨.由于贫困人口高度集中分布在五个贫困小区,区域性贫困现象突出.该文分析区情,从能力建设的战略角度,提出开发以优质杂交玉米、苡仁米为主的种植业,以山苍子、金银花、天麻为主的药材业,以生猪、黑山羊、黄牛为主的畜牧业,以大理石为主的建材加工业,以开发观光旅游资源为主的旅游业等五大优势产业.把四大优势农产品农业基地的建设、节水农业、小流域综合治理、异地开发、乡镇企业的投入和管理、观光旅游等作为重点扶持项目.     

Surface water deficiency zoning of China based on surface water deficit index (SWDI)

China’s economic and social development is severely restricted by regional water deficiency, and the determination of water deficiency level in different regions is an important basis of water resource management. In this study, we zoned 32 provinces of China into five surface water deficiency levels based on surface water deficit index derived from the Chinese meteorological satellite FY-2C images. The result shows that China is facing serious water shortage crisis with only 15.44% of total area without water deficiency, which is located in the south and southeast coast. More than 60% of total area of China suffered from severe or extremely water deficiency, which are mainly distributed in western and northern regions. Jingjinji area (namely Beijing, Tianjin and Hebei province), which is a special region with high amount of gross domestic product and relative abundant water resources, is suffering from severe water deficiency. It revealed that water resources were interacted with regional development and water management should consider local conditions. To Jingjinji area, water management should focus on adjustment of industrial structure, urban expansion control and scientific water resources allocation. In general, the surface water deficit index based water deficiency zoning will be of significant value to be applied in water resources management at regional scales.     

香港巨牡蛎对3种微藻的选择性摄食研究

从微藻粒径大小、饵料密度以及营养价值角度,选取牟氏角毛藻（Chaetoceros muelleri）、亚心形扁藻（Platymonas subcordiformis）、球等鞭金藻（Isochrysis galbana）分别作为硅藻、绿藻和金藻的代表,开展了不同规格的香港巨牡蛎对3种微藻在同等密度、同等生物量混合条件下的摄食选择性研究。结果显示,香港巨牡蛎在两种不同混合藻条件下对3种不同微藻摄食选择性有显著性差异（P<0.01）。3种藻相同密度混合条件下,大、中、小3种规格香港巨牡蛎更倾向摄食粒径较大的亚心形扁藻,且贝类规格越大选择倾向性越低,摄食选择效率分别为0.32、0.35、0.48,对球等鞭金藻无明显选择性。3种藻等生物量混合条件下,香港巨牡蛎对亚心形扁藻和球等鞭金藻的摄食有选择性,且规格大小对选择效率影响显著（P<0.01）,个体越小选择性越强,小规格香港巨牡蛎倾向滤食亚心形扁藻（P<0.01）,大、中规格更倾向摄食粒径较小的球等鞭金藻。两种混合条件下,香港巨牡蛎都对牟氏角毛藻都有负的选择效率,而且牟氏角毛藻密度越高负值绝对值越大。微藻的细胞大小、形状、营养价值以及香港巨牡蛎的个体大小都对摄食选择性有着明显的影响,香港巨牡蛎的摄食选择性在现场海区中还明显受到生境及食物条件的限制。     

TRIPLOIDY INDUCTION WITH HEAT SHOCKS TO -PENAEUS CHINENSIS- AND THEIR EFFECTS ON GONAD DEVELOPMENT

ＩＮＴＲＯＤＵＣＴＩＯＮＩｎｒｅｃｅｎｔｙｅａｒｓ,ｓｃｉｅｎｔｉｓｔｓｐａｉｄｉｎｃｒｅａｓｉｎｇａｔｔｅｎｔｉｏｎｔｏｐｏｌｙｐｌｏｉｄｙｂｒｅｅｄｉｎｇｏｆａｑｕａｔｉｃａｎｉｍａｌｓ.Ｓｔｕｄｉｅｓｏｎｔｒｉｐｌｏｉｄｙｂｒｅｅｄｉｎｇｏｆｆｉｓｈａｎｄｍｏｌｌｕｓｃｈａｖｅｍａｄｅｎｏｔｉｃｅａｂｌｅｐｒｏｇｒｅｓｓ.Ｔｈｅｒｅａｒｅｒｅｐｏｒｔｓｏｆｌａｒｇｅｓｃａｌｅｃｏｍｍｅｒｃｉａｌｃｕｌｔｕｒｅｏｆｔｒｉｐｌｏｉｄｓｉｎｄｕｃｅｄｉｎｓｏｍｅｓｐｅｃｉｅｓ.Ｔｈｅｒｅｐｏｒｔｅｄ…     

SO2-4/Fe2O3固体超强酸催化合成乙酸丁酯

制备固体超强酸SO4 2 - /Fe2 O3,并测定其红外光谱。以乙酸和正丁醇为反应物、固体超强酸SO4 2 - /Fe2 O3为催化剂 ,进行合成乙酸丁酯的研究。实验结果表明 ,固体超强酸SO4 2 - /Fe2 O3在合成乙酸丁酯反应中的催化活性与浓硫酸相当 ,用 0 1mol正丁醇与 0 2mol乙酸反应 ,催化剂用量 0 3g ,回流时间 90min ,乙酸丁酯收率为 63 8%。     

海浪外观谱及其平衡域

定义了海浪能量的广义或n阶外观分布,导出了n阶海浪外观谱的解析形式,讨论了n阶外观谱的平衡域.结果表明,n阶外观谱的平衡域指数为-(3+n);平衡域指数上界为-3.任何波动现象,只要Fourier迭加原理和射线理论对它们的描述足够准确,则本文的结论皆成立.     

Analysis of groundwater-level fluctuation in a coastal confined aquifer induced by sea-level variation

Groundwater responses to tide fluctuations in different hydrogeological situations have been investigated for many years. Various solutions have been derived using the assumption that tides are composed of sinusoidal components, neglecting non-periodic variables. This approach has resulted in the introduction of some inaccuracy in predictions of groundwater responses to sea-level variation. To resolve this problem, this study used the Fourier sine transform method to derive an analytical solution based on the measured sea-level boundary. Compared with an analytical solution based on a sinusoidal assumption and a numerical solution generated by MODFLOW, this solution provided better performance in groundwater-level prediction in a coastal confined aquifer in Zhuhai City, China. The hydrogeological parameters estimated by the three aforementioned methods fitted well with those estimated by field surveys and pumping tests. The introduced analytical solution not only reflects the physical mechanisms of tide-induced groundwater-level fluctuation, but also reveals the non-periodic fluctuation of groundwater level caused by sea-level variation. This solution may also be used to evaluate groundwater responses to random mechanical stresses.     

An Estimation of the Coronal Magnetic Field Strength From Spectrographic Observations in the Microwave Range

Solar radio emission observations in the microwave frequency range show fine structures consisting of a number of almost parallel narrow-frequency bands. We interpret these bands as plasma emission at cyclotron harmonics. This emission is generated by the anisotropic electron beam, which excites longitudinal waves at a normal Doppler effect resonance. Subsequently, the longitudinal waves convert to radio emission at the second harmonic of the longitudinal wave frequency, and sometimes to the fundamental harmonic. The magnetic field strength is estimated on the basis of such a model in the microwave burst sources at 100–200 G. Estimates of the density variations are also made.