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991.
Preliminary regional estimation of carbon sink flux by carbonate rock corrosion: A case study of the Pearl River Basin 总被引:5,自引:0,他引:5
The formation of carbonate rocks has had a dramatic sink effect on atmospheric CO2 throughout geological time.The wide global distribution of carbonate rocks and their strong sensitivity to climate change mean that carbonate rock corrosion consuming air/soil CO2 can play an important role in the global carbon cycle.The carbon sink accounts for 12.00%-35.29% of the missing carbon in the global carbon cycle.Using the Pearl River Basin as a case study,we analyzed comprehensively the factors impacting karstific... 相似文献
992.
Colloidal photonic crystals (PCs) with desired wettabilities are of particular importance in various applications. Inspired by biological PCs, such as those of butterfly wings and peacock feathers, which all have evolved to have specific wettability, Professor Song Yanlin and his group in the Laboratory of New Materials, Institute of Chemistry, Chinese Academy of Sciences developed unique approaches to engineer colloidal PCs with desired wettability, based on the well-designed building blocks of latex particles. The range of wettability of these col- loidal PC films could be tailored from superhydrophobicity to superhydrophilicity and even superoleophobicity, by varying the surface 相似文献
993.
Yong Wei QiuGang Zong ZuYin Pu WeiXing Wan JianJun Liu SuiYan Fu QuanQi Shi 《科学通报(英文版)》2011,56(11):1117-1122
It is believed that a southward interplanetary magnetic field (IMF) is mainly responsible for the energy input from solar
wind into the magnetosphere. This paper presents an unusual case of strong anti-sunward plasma flow (up to 2 km/s) in the
polar cap ionosphere and large cross-polar cap potential (CPCP) during a period of horizontal IMF (|B
Z
| < 2 nT) observed by both ACE (at the L1 point) and Geotail (on the dusk flank of the magnetosheath). The CPCP is even higher
than that under preceding B
Z
≈ −23 nT. Furthermore, GOES8 observed that the magnetosheath field turns northward as the anti-sunward plasma flow and CPCP
start to increase, which implies that the magnetosheath field interacting with the Earth’s magnetopause has significantly
rotated and differs from the IMF observed by ACE and Geotail. In accordance with previous theoretical work, we suggest that
the magnetic field line draping produces a southward magnetosheath field and enhances anti-sunward plasma flow and the CPCP. 相似文献
994.
High performance MFI-type zeolite membranes on the outer surface of α-Al 2 O 3 hollow fibers were synthesized by secondary growth method using pure silica sol without an organic template. X-ray diffraction was used to characterize the phase structure of both the seed layer and zeolite membrane. The morphologies of the seed layer and zeolite membrane were examined by scanning electron microscopy. The zeolite membrane achieved an extraordinary H 2 /CO 2 separation factor of 10 with a high H 2 permeance of 5.56 10 -7 mol m -2 s -1 Pa -1 at 723 K. 相似文献
995.
The probability density function of irradiance fluctuations in a turbulent atmosphere remains an open topic of research.It is generally considered that the speckle field has an elliptical-Gaussian speckle distribution,but because of its complexity there is still no exact analytical solution.By introducing the concept of random fluctuation intensity and using an equiprobability density ellipse,exact models of the random fluctuation intensity and its phase are proposed.Through theoretical analysis and numerical simulation,it is concluded that the random fluctuation intensity and its corresponding phase are independent only under the circular-Gaussian approximation. 相似文献
996.
JinQing Jiang HaiTang Zhang GuoYing Fan JinYou Ma ZiLiang Wang JianHua Wang 《科学通报(英文版)》2011,56(25):2698-2705
19-Nortestosterone (NT) has been illegally used in horse racing to boost physical performance, and in animal husbandry to accelerate weight gain. To monitor the abuse of NT, our goal was to develop a commercial enzyme linked immunosorbent assay (ELISA) kit. For this purpose, hybridomas were prepared by fusing NS0 mouse myeloma cells with splenocytes isolated from immunized BALB/c mouse. Noncompetitive and competitive indirect ELISA were used to screen positive cell clones. To optimize the indirect competiti... 相似文献
997.
WenJue Zhong DongHong Wang XiaoWei Xu BingYi Wang Qian Luo Satyanarayanan Senthil Kumaran ZiJian Wang 《科学通报(英文版)》2011,56(3):275-284
Phenolic compounds exist widely in the influents and effluents of sewage treatment plants (STPs) and most are un-regulated.
In this study, a gas chromatography-mass spectrometry (GC-MS) method for the simultaneous analysis of 50 phenolic compounds
in wastewater was developed. Deconvolution technology was used to identify contaminants that are covered by co-extracted materials.
A mass spectral library containing all 50 silylated phenolic compounds was first established and used for deconvolution. Twelve
typical phenolic compounds were selected to optimize the sample preparation procedures. Solid-phase extraction using a C18
cartridge coupled with an HLB cartridge was used for pre-concentration and dichloromethane was used for elution. The solutes
were derivatized and analyzed by GC-MS. The blank and matrix spike recoveries ranged from 57.46% to 136.4% and 47.87% to 114.8%,
respectively. Method detection limits ranged from 3.64 to 97.64 ng L−1. The relative standard deviations of all the recovery experiments were lower than 13.6%. The instrument limits of quantification
ranged from 0.7 to 87.7 pg. The method has been applied to analyze the influents and effluents of 5 Chinese STPs. Except for
regulated phenolic compounds (phenol and 2,4,6-trichlorophenol), three un-regulated phenolic compounds, including 2-chlorophenol,
2,5-dichlorophenol and 2,4-dichloro-3-ethyl-6-nitrophenol were identified in the effluent wastewater. The detected concentrations
of un-regulated phenolic compounds could possibly cause environmental effects, indicating that immediate attention is required
to prevent complications. 相似文献
998.
Conservation equations for sensible and latent entransy are established for flue gas turbulent heat transfer with condensation
in a tube, and the entransy dissipation expression is deduced. The field synergy equation is obtained on the basis of the
extremum entransy dissipation principle for flue gas turbulent heat transfer with condensation. The optimal velocity field
is numerically obtained by solving the field synergy equation. The results show that the optimal velocity field contains multiple
longitudinal vortices near the tube surface. These improve the synergy not only between the velocity and temperature fields
but also between the velocity and vapor concentration fields. Therefore, the turbulent heat and mass transfers are significantly
enhanced. 相似文献
999.
Fan Yu Jun Xiao XiangYang Liang ShaoJun Liu GongJian Zhou KaiKun Luo Yun Liu Wei Hu YaPing Wang ZuoYan Zhu 《科学通报(英文版)》2011,56(16):1679-1684
Triploid carp (100%) with 150 (3n=150) chromosomes were obtained by crossing the females of improved tetraploid hybrids (♀,
4n=200) of red crucian carp (♀)×common carp (♂) with the males of diploid yellow river carp (♂, 2n=100). The crosses yielded
transgenic triploid carp (positive triploid fish, 44.2% of the progeny) and non-transgenic triploid carp (negative triploid
fish). Histological examination of the gonads of 24-month-old positive triploid fish suggested they were sterile and the fish
were not able to produce mature gametes during the breeding season. Morphologically, both the positive and negative triploid
fish were similar. They had a spindle-shaped, laterally compressed, steel grey body with two pairs of barbells. Most of the
quantifiable traits of the triploid carp were intermediate between those of the two parents. The positive and negative triploid
fish were raised in the same pond for 2 years. The mean body weight of the positive triploid fish was 2.3 times higher than
the negative triploid fish. The weight of the largest positive triploid fish was 2.91 times higher than that of the largest
negative triploid fish. Thus, we produced fast-growing transgenic triploid carp that have a reduced ecological risk because
of their inability to mate and produce progeny. 相似文献
1000.
Predicting the spread of nuclear radiation from the damaged Fukushima Nuclear Power Plant 总被引:1,自引:0,他引:1
FangLi Qiao GuanSuo Wang Wei Zhao JieChen Zhao DeJun Dai YaJuan Song ZhenYa Song 《科学通报(英文版)》2011,56(18):1890-1896
Japan suffered a M9.0 earthquake and massive tsunami on March 11, 2011, which seriously damaged the Fukushima Nuclear Power Plant and caused a nuclear crisis. The spread of nuclear radiation from the power plant through the atmosphere and ocean was predicted with a short-term climate forecasting model and an ocean circulation model under some idealized assumptions. If nuclear matter were leaked in the near-ground layer of 992 hPa, the climate model results show that the nuclear radiation would cover North America 10 days after the initial leakage, with the concentration at the forefront dramatically reduced to 10 millionths of the initial model concentration at the source. The radiation would span Europe in 15 days and cover much of the Northern Hemisphere in 30 days. If the initial leakage was assumed to occur in the layer 5000-m above the ground, the radiation would cover Europe in 10 days and cover much of the Northern Hemisphere in 15 days. Moreover, under the assumption that the nuclear matter leaked in the 10000-m layer, the radiation would affect much of China after 10 days. The ocean circulation model indicates that the nuclear material would be slowly transported northeast of Fukushima and reach 150°E in 50 days, and the nuclear debris in the ocean would be confined to a narrow band. Compared with the spread in the ocean, the area affected by leaked nuclear radiation in the atmosphere would be very large. Atmospheric monitors in North America and Europe will be helpful for estimating the effect in China of any leaked nuclear material. 相似文献