在全球气候变暖的背景下,准确估计海-气界面CO_2通量显得非常重要。海-气界面CO_2通量通常利用块体公式,由气体交换速率与大气和海洋的CO_2分压差(ΔpCO_2)的乘积来计算。影响气体交换速率的因素很多,但一般经验性地与风速相联系,其测...在全球气候变暖的背景下,准确估计海-气界面CO_2通量显得非常重要。海-气界面CO_2通量通常利用块体公式,由气体交换速率与大气和海洋的CO_2分压差(ΔpCO_2)的乘积来计算。影响气体交换速率的因素很多,但一般经验性地与风速相联系,其测量方法通常有物质平衡法和涡相关法,后者给出的结果比前者大。基于前人的两类观测数据,提出了一个以风速为函数的气体交换速率新方案。在此基础上,基于最新的SOCATv2(Surface Ocean CO_2Atlas version 2)的ΔpCO_2数据集,计算了1982—2011年海洋对CO_2的净吸收量及其年变化,发现2001年海洋净吸收量存在一个最小值,2001年之后,海洋净吸收量迅速增加,而这一年变化特征主要由ΔpCO_2的年变化特征所决定,风速的影响可以忽略。展开更多
Prophyra-334 was prepared by methanol extraction and HPLC methods from marine algae （dried laver）. It is a sunscreen compound that has good absorption of ultraviolet radiations in the wavelength ranges of 200-400 nm...Prophyra-334 was prepared by methanol extraction and HPLC methods from marine algae （dried laver）. It is a sunscreen compound that has good absorption of ultraviolet radiations in the wavelength ranges of 200-400 nm. The absorption maximum wavelength of prophyra-334 is at 334 nm, so defined the name. The molar extinction coefficient （ε） of prophyra-334 in aqueous solution at 334 nm wavelength is 4.23×10^4. The absorption of prophyra-334 in organic solvents differs in aqueous solutions. In polar organic solvents, the absorption maximum wavelength of prophyra-334 has a slight shift toward longer wavelength compared with that in pure water. On the contrary, in inert non-polar organic solvents, the absorption maximum wavelength and the shape of absorption spectra of prophyra-334 are changed. The effects of organic solvents on prophyra-334 stability suggested that： （1） the absorbance of prophyra-334 in water is generally constant at temperature of 60℃ in 24 h, meaning that prophyra-334 is quite stable in water; （2） the absorbance of prophyra-334 in ethanol and hexane decreases at the same condition. The stability of prophyra-334 in organic solvents is less than that in aqueous solution. In benzene, the prophyra-334 is very instable.展开更多
A previously developed model was modified to derive three phytoplankton size classes (micro-, nano-, and pico-phytoplankton) from the overall chlorophyll-a concentration, assuming that each class has a specific absorp...A previously developed model was modified to derive three phytoplankton size classes (micro-, nano-, and pico-phytoplankton) from the overall chlorophyll-a concentration, assuming that each class has a specific absorption coefficient. The modified model performed well using in-situ data from the northern South China Sea, and the results were reliable and accurate. The relative errors of the size-fractioned chlorophyll-a concentration for each size class were: micro-:21%, nano-:41%, pico-:26%, and nano+pico:23%. The model was then applied on ocean color remote sensing data to examine the distribution and variation of phytoplankton size classes in northern South China Sea on a large scale.展开更多
In the visible spectrum, the atmospheric attenuations to sunlight mainly include aerosol scattering, atmospheric molecule Rayleigh scattering and ozone absorption, while in the near-infrared spectrum (from 650 nm to 1...In the visible spectrum, the atmospheric attenuations to sunlight mainly include aerosol scattering, atmospheric molecule Rayleigh scattering and ozone absorption, while in the near-infrared spectrum (from 650 nm to 1 000 nm), we must take water-vapor absorption into account. Based on the atmospheric correction theory, using spectrum irradiance data measured by Instantaneous Ground spectrometer, ozone content measured by Microtops Ⅱozone monitor, water-vapor content and aerosol optical thickness measured by sun photometer, we give a new way to study water-vapor absorption to sunlight, and the result shows that the main peak values of water-vapor absorption coefficients are 0.025 cm-1, 0.073 cm-1, 0.124 cm-1, 0.090 cm-1, 0.141 cm-1 and 0.417 cm-1, which respectively lie at 692 nm, 725 nm, 761 nm, 818 nm, 912 nm and 937 nm.展开更多
In order to determine and assess the concentrations of trace elements in coral reefs sediments from Red Sea of Yemen, sediment samples were collected, treated and analyzed for cadmium, chromium, cobalt, copper, mangan...In order to determine and assess the concentrations of trace elements in coral reefs sediments from Red Sea of Yemen, sediment samples were collected, treated and analyzed for cadmium, chromium, cobalt, copper, manganese, nickel, lead, iron, zinc and vanadium by the atomic absorption spectrometric analysis. The result is that cadmium, cobalt and lead concentrations were high and other elements are low or the same as natural background. It is concluded that the high cadmium, cobalt and lead levels in coral reefs sediments will have negative effects on marine life of the sites, so further researches are needed to characterize the sources fate, biogeochemical processes and impacts of these trace elements on coral reefs and marine of the region.展开更多
This paper presents a composite interaction formula based on the discrete-interaction operator of wave-wave nonlinear interaction for deriving its adjoint source function in the wave assimilation model. Assimilation e...This paper presents a composite interaction formula based on the discrete-interaction operator of wave-wave nonlinear interaction for deriving its adjoint source function in the wave assimilation model. Assimilation experiments were performed using the significant wave heights observed by the TOPES/POSEIDON satellite, and the gradient distribution in the physical space was also analyzed preliminarily.展开更多
文摘在全球气候变暖的背景下,准确估计海-气界面CO_2通量显得非常重要。海-气界面CO_2通量通常利用块体公式,由气体交换速率与大气和海洋的CO_2分压差(ΔpCO_2)的乘积来计算。影响气体交换速率的因素很多,但一般经验性地与风速相联系,其测量方法通常有物质平衡法和涡相关法,后者给出的结果比前者大。基于前人的两类观测数据,提出了一个以风速为函数的气体交换速率新方案。在此基础上,基于最新的SOCATv2(Surface Ocean CO_2Atlas version 2)的ΔpCO_2数据集,计算了1982—2011年海洋对CO_2的净吸收量及其年变化,发现2001年海洋净吸收量存在一个最小值,2001年之后,海洋净吸收量迅速增加,而这一年变化特征主要由ΔpCO_2的年变化特征所决定,风速的影响可以忽略。
基金This study was supported by SRF for ROCS, SEM and Natural ScienceFoundation of Qingdao (No. 04-2-JZ-110)
文摘Prophyra-334 was prepared by methanol extraction and HPLC methods from marine algae （dried laver）. It is a sunscreen compound that has good absorption of ultraviolet radiations in the wavelength ranges of 200-400 nm. The absorption maximum wavelength of prophyra-334 is at 334 nm, so defined the name. The molar extinction coefficient （ε） of prophyra-334 in aqueous solution at 334 nm wavelength is 4.23×10^4. The absorption of prophyra-334 in organic solvents differs in aqueous solutions. In polar organic solvents, the absorption maximum wavelength of prophyra-334 has a slight shift toward longer wavelength compared with that in pure water. On the contrary, in inert non-polar organic solvents, the absorption maximum wavelength and the shape of absorption spectra of prophyra-334 are changed. The effects of organic solvents on prophyra-334 stability suggested that： （1） the absorbance of prophyra-334 in water is generally constant at temperature of 60℃ in 24 h, meaning that prophyra-334 is quite stable in water; （2） the absorbance of prophyra-334 in ethanol and hexane decreases at the same condition. The stability of prophyra-334 in organic solvents is less than that in aqueous solution. In benzene, the prophyra-334 is very instable.
基金Supported by the National Natural Science Foundation of China (Nos.U0933005,41076014,40906021,41176035)the National High Technology Research and Development Program of China (863 Program)(No.2007AA092001-02)
文摘A previously developed model was modified to derive three phytoplankton size classes (micro-, nano-, and pico-phytoplankton) from the overall chlorophyll-a concentration, assuming that each class has a specific absorption coefficient. The modified model performed well using in-situ data from the northern South China Sea, and the results were reliable and accurate. The relative errors of the size-fractioned chlorophyll-a concentration for each size class were: micro-:21%, nano-:41%, pico-:26%, and nano+pico:23%. The model was then applied on ocean color remote sensing data to examine the distribution and variation of phytoplankton size classes in northern South China Sea on a large scale.
基金Financial support was provided by The National High Technology Research and Development Program of China(863 Program):No 2001AA633030 and 2001AA633080.
文摘In the visible spectrum, the atmospheric attenuations to sunlight mainly include aerosol scattering, atmospheric molecule Rayleigh scattering and ozone absorption, while in the near-infrared spectrum (from 650 nm to 1 000 nm), we must take water-vapor absorption into account. Based on the atmospheric correction theory, using spectrum irradiance data measured by Instantaneous Ground spectrometer, ozone content measured by Microtops Ⅱozone monitor, water-vapor content and aerosol optical thickness measured by sun photometer, we give a new way to study water-vapor absorption to sunlight, and the result shows that the main peak values of water-vapor absorption coefficients are 0.025 cm-1, 0.073 cm-1, 0.124 cm-1, 0.090 cm-1, 0.141 cm-1 and 0.417 cm-1, which respectively lie at 692 nm, 725 nm, 761 nm, 818 nm, 912 nm and 937 nm.
文摘In order to determine and assess the concentrations of trace elements in coral reefs sediments from Red Sea of Yemen, sediment samples were collected, treated and analyzed for cadmium, chromium, cobalt, copper, manganese, nickel, lead, iron, zinc and vanadium by the atomic absorption spectrometric analysis. The result is that cadmium, cobalt and lead concentrations were high and other elements are low or the same as natural background. It is concluded that the high cadmium, cobalt and lead levels in coral reefs sediments will have negative effects on marine life of the sites, so further researches are needed to characterize the sources fate, biogeochemical processes and impacts of these trace elements on coral reefs and marine of the region.
文摘This paper presents a composite interaction formula based on the discrete-interaction operator of wave-wave nonlinear interaction for deriving its adjoint source function in the wave assimilation model. Assimilation experiments were performed using the significant wave heights observed by the TOPES/POSEIDON satellite, and the gradient distribution in the physical space was also analyzed preliminarily.
