CCD Photometry and Long-Term Optical Variability of 3C 345

This paper presents evidence for long-term optical variability and colour behaviour of the blazar 3C 345 (1641+399, z=0.595). Our results show that the amplitude of the optical variations of 3C 345 has been only about 3 magnitudes from its photometric history; existent significant correlation between brightness and colours is found for 3C 345. Our recent CCD photometry of 3C 345 in May 1996 and May 1997 showed that they are in good agreement with our prediction of the optical variability period of about 10 years (see Zhang et al., 1998; Webb et al., 1988). This revised version was published online in July 2006 with corrections to the Cover Date.     

V-3θ图的结构与"98.6"暴雨过程预测分析

V-3θ图是成都气象学院欧阳首承教授设计出来的运用图像结构来预测天气的结构预测方法。主要利用大气中的压、湿、湿、风的垂直分布,判断大气滚流对天气演变的影响来预报天气转折性变化。利用V-3θ图对桂林站1998年6月份的暴雨过程作一个综合分析。结果几次特强的降水都在V-3θ图上有较好的反映。该方法对无明显降水的天气也能作定性的判断。     

Club convergence and spatial distribution dynamics of carbon intensity in China’s construction industry

Climate change caused by carbon emissions continuously threatens sustainable development. Due to China’s immense territory, there are remarkable regional differences in carbon emissions. The construction industry, which has strong internal industrial differences, further leads to carbon emission disparity in China. Policymakers should consider spatial effects and attempt to eliminate carbon emission inequality to promote the sustainable development of the construction industry and realize emission reduction targets. Based on the classic Markov chain and spatial Markov chain, this paper investigates the club convergence and spatial distribution dynamics of China’s carbon intensity in the construction industry from 2005 to 2014. The results show that the provincial carbon intensity in the construction industry is characterized by “convergence clubs” during the research period, and very low-level and very high-level convergence clubs have strong stability. Moreover, the carbon intensity class transitions of provinces tend to be consistent with that of their neighbors. Furthermore, the transition of carbon intensity types is highly influenced by their regional backgrounds. The provinces with high carbon emissions have a negative influence on their neighbors, whereas the provinces with low carbon emissions have a positive influence. These analyses provide a spatial interpretation to the “club convergence” of carbon intensity.     

青南高原大气降水变化规律及其对黄河上游地区水资源的影响

利用1959～1997年黄河上游地区降水、流量资料,用EOF、REOF等数理统计方法,分析了黄河上游地区降水与流量之间的关系,并对黄河上游地区的水资源进行了估算。分析得出：龙羊峡年入库流量的丰枯主要与黄河上游地区的年降水量有关,春季流量的丰枯主要与上一年秋季的流量、春季的降水量有关,夏、秋季流量的丰枯主要与同期的降水量有关。     

Preliminary assessment of CO2 transport and storage costs of promising source–sink matching scenarios in Guangdong province,China

Guangdong is the most economically developed province in China, which is a large CO₂ emitter and hence is faced with severe carbon reduction pressures. In this paper, a cost assessment methodology based on scenario analysis is presented. A CO₂ source and sink database was built at Guangdong after detailed investigations on the point sources and sedimentary basins. Fifteen transport and five storage scenarios were defined and studied, respectively. Cost estimates based on these scenarios show that during its lifetime, the costs of both transport and storage depend on the amount of CO₂ processed. More CO₂ being processed will bring down the unit costs of both transport and storage. However, it was observed that there is a cost inflection point between the storage amount of 35.2 and 52.8 Mt/year, which means that as the storage amount increases, the storage cost will first decrease and then increase. Source region S1 in Guangdong has been recommended for an early chance of CO₂ storage. Preliminary cost comparisons have shown that the results presented in this study are reasonable, but to improve the cost assessment accuracy of offshore CO₂ storage, a methodology based on a CO₂ storage design that can integrate local prices needs to be further developed.     

珠海海岛旅游的特点及政策探讨

珠海市海岛旅游资源丰富,开发潜力巨大,但由于起步较晚,发展缓慢,与世界上一些开发较早、水平较高的国家相比有较大差距。文章首先回顾了海岛旅游的相关文献,实地调查分析了珠海海岛旅游的发展现状和特点,并充分借鉴国外海岛旅游开发的成功经验,在此基础之上,提出了珠海海岛旅游可持续发展的一系列措施。     

Composition and Useful Properties of Tailings of Marine Manganese Nodules and Crusts

ABSTRACT

Marine manganese nodules and crusts, when processed, yield tailings which may be utilized for environmental and economic benefit. The key to the reasonable and effective utilization of these tailings lies in making a systematic appraisal of their composition and properties. This article gives an introduction to the investigation of manganese tailings properties. The tailings have a high iron and/or manganese content, high surface area, high porosity, and fine grain size. Some tailings have a high rare earth element content which is valuable. They may also have high SO₃, arsenic, and uranium contents which are harmful. Depending on the process used to produce the tailings, there will likely be some differences in chemical composition, mineral assemblages, surface area and adsorption capability, pore diameter and volume, density and pH. In assigning potentially beneficial applications for these tailings, these differences should be taken into account to optimize utilization.     

Solar-, monsoon- and Kuroshio-influenced thermocline depth and sea surface salinity in the southern Okinawa Trough during the past 17,300 years

Factors influencing millennial-scale variability in the thermocline depth (vertical mixing) and sea surface salinity (SSS) of the southern Okinawa Trough (OT) during the past 17,300 years were investigated based on foraminifer oxygen isotope records of the surface dweller Globigerinoides ruber sensu stricto and the thermocline dweller Pulleniatina obliquiloculata in the AMS ¹⁴C dated OKT-3 core. The thermocline depth is influenced by surface thermal buoyancy (heat) flux, in turn controlled by the annual mean insolation at 30°N and the strength of the East Asian winter monsoon (EAWM). Strong insolation and weak EAWM tend to increase buoyancy gain (decrease buoyancy loss), corresponding to shallow thermocline depths, and vice versa. Regional SSS is influenced by the global ice volume, the Kuroshio Current (KC), and vertical mixing. A deep thermocline coincides with a high SSS because strong vertical mixing brings more, saltier subsurface KC water to the surface, and vice versa. Local SSS (excluding the global ice volume effect) became lower in the northern OT than in the southern OT after ~9.2 ka, implying that Changjiang diluted water had stronger influence in the northern sector. SSS show no major changes during the Bølling/Allerød and Younger Dryas events, probably because the KC disturbed the North Atlantic signals. This argues against earlier interpretations of sea surface temperature records of this core. Wavelet and spectral analyses of the Δδ¹⁸O_P-G (δ¹⁸O of P. obliquiloculata minus G. ruber s.s.) and δ¹⁸O_local records display 1,540-, 1,480-, 1,050-, 860-, 640-, and 630-year periods. These are consistent with published evidence of a pervasive periodicity of 1,500 years in global climate as well as EAWM and KC signatures, and a fundamental solar periodicity of 1,000 years and intermediary derived periodicity of 700 years.     

Optical system research of multi-object fiber spectroscopic survey telescope

In the first part of this paper,four different Cassegrain optical systems with their correctors are designed and studied for multi-object fiber slit spectroscopic survey.The aperture in 6.5 m and field of view 3°are taken for these optical systems.Assuming observation wavelength range is 0.365–0.95μm,the maximum zenith distance for observing is 60°,the maximum diameter of these lenses is 1.66 m,the altitude of the telescope site is 2500 m,two correctors are composed of 4-piece lenses and the other two are 5-piece lenses.The results obtained are:f-ratio about 3.7,the image quality for all four systems with EE80D≤0.60′′,the linear diameter of the focal surface is about 1.2 m and 11 000 fibers can be set on it.Considering the limit of size of fused silica and optical glass,the maximum diameter for lens is about 1.7 m.Such a 6.5 m telescope is about the largest one if using the above correctors.Considering the multiobject spectroscopic survey is greatly important,we also studied some telescope optical systems having their aperture near or larger than 10 m used for the multi-object fiber spectroscopic survey.Such ideas are introduced in the last section of this paper.