The aim of the study is to investigate the contents of trace element Se, Cd, Pb in three plants including burdock, ginkgol and garlic via graphite furnace atomic absorption and standard addition method. The results sh...The aim of the study is to investigate the contents of trace element Se, Cd, Pb in three plants including burdock, ginkgol and garlic via graphite furnace atomic absorption and standard addition method. The results show that Se in burdock stem, skin and leaf are 32.40, 48.63, 38.10 μg/g, respectively; Cd in burdock stem, skin and leaf are 0. 160 0, 0. 300 0, 0. 140 0 μg/g, respectively; Cd in burdock stem, skin and leaf are 2. 020, 3. 960, 2. 410 μg/g, respectively. In the ginkgo and ginko leaf, Se contents are 17.63 and 16.91 μg/g, respectively ; for Cd are 0. 181 0 and 0.2020μg/g, respectively ; for Pb are 3. 572 and 4. 021 μg/g, respectively. In garlic, Se, Cd and Pb are 73. 900 0, 6. 900 0 and 0. 390 0, respectively. All the standard deviations of measured results are below 2.3%, recovery rate are from 99% to 101%.展开更多
Chitosan, an excellent biomedical material, has received a widespread in vivo application. In contrast, its metabolism and distribution once being implanted were less documented. In this study, the pharmacokinetics an...Chitosan, an excellent biomedical material, has received a widespread in vivo application. In contrast, its metabolism and distribution once being implanted were less documented. In this study, the pharmacokinetics and biodegradation of fluorescein isothiocyanate(FITC) labeled and muscle implantation administrated chitosan in rats were investigated with fluorescence spectrophotometry, histological assay and gel chromatography. After implantation, chitosan was degraded gradually during its distribution to diverse organs. Among the tested organs, liver and kidney were found to be the first two highest in chitosan content, which was followed by heart, brain and spleen. Urinary excretion was believed to be the major pathway of chitosan elimination, yet 80% of chitosan administered to rats was not trackable in their urine. This indicated that the majority of chitosan was degraded in tissues. In average, the molecular weight of the degradation products of chitosan in diverse organs and urine was found to be <65 k Da. This further confirmed the in vivo degradation of chitosan. Our findings provided new evidences for the intensive and safe application of chitosan as a biomedical material.展开更多
The author determined the occurrence of indole-3-acetic acid in sixteen Chinese marine algae collected from the east coast of China with fluorescence spectrophotometry (FS) and wheat coleop- tile bioanalysis methods (...The author determined the occurrence of indole-3-acetic acid in sixteen Chinese marine algae collected from the east coast of China with fluorescence spectrophotometry (FS) and wheat coleop- tile bioanalysis methods (WCB). The concentration of indole-3-acetic acid (IAA) presented was from 1.1–46.9 ng/g Fw (fresh weight) with FS and 5.3–110.2 ng/g Fw with WCB. The results by the two meth- ods were in the orders of 10-3–103 ng/g Fw reported previously from multiple references.展开更多
We propose a bio-optical inversion model that retrieves the absorption contributions of phytoplankton and colored detrital matter(CDM),as well as the phytoplankton size classes(PSCs),from total minus water absorption ...We propose a bio-optical inversion model that retrieves the absorption contributions of phytoplankton and colored detrital matter(CDM),as well as the phytoplankton size classes(PSCs),from total minus water absorption spectra.The model is based on three-component separation of phytoplankton size structure and a genetic algorithm.The model performance was tested on two independent datasets(the NASA bio-Optical Marine Algorithm Dataset(NOMAD) and the northern South China Sea(NSCS) dataset).The relationships between the estimated and measured values were strongly linear,especially for aCDM(412),and the Root Mean Square Error(RMSE) of the CDM exponential slope(SCDM) was relatively low.Next,the inversion model was directly applied to in-situ total minus water absorption spectra determined by an underwater meter during a cruise in September 2008,to retrieve the phytoplankton size structure in the seawater.By comparing the measured and retrieved chlorophyll a concentrations,we demonstrated that total and size-specific chlorophyll a concentrations could be retrieved by the model with relatively high accuracy.Finally,we applied the bio-optical inversion model to investigate changes in phytoplankton size structure induced by an anti-cyclonic eddy in the NSCS.展开更多
Pyrolusite reduction processes by three major biomass components cellulose,hemicelluloses and lignin,represented by CP,HP and LP,respectively,were investigated by thermogravimetric analyzer coupled with Fourier transf...Pyrolusite reduction processes by three major biomass components cellulose,hemicelluloses and lignin,represented by CP,HP and LP,respectively,were investigated by thermogravimetric analyzer coupled with Fourier transform infrared spectrometry(TG-FTIR).The Sestak-Berggren(SB) equation was used to evaluate the kinetics of reduction processes.TG analysis reveals that the main reduction processes occur at 250-410 ℃,220-390 ℃,and 190-410 ℃ for CP,HP,and LP,respectively.FT-IR and XRD results indicate that various reducing volatiles(e.g.aldehydes,furans,ketones and alcohols) are produced from the pyrolysis with the three major components,which directly reduce MnO_2 in ore to MnO.The processes are described by the SB equation with three parameters(m,n,p).Their non-zero values suggest that pyrolusite reduction is controlled by the diffusion of reducing gaseous products through an ash/inert layer associated with minerals.The apparent activation energies for pyrolusite reduction by CP,HP and LP are 40.48,25.70 and 40.10 kJ·mol^(-1),respectively.展开更多
With the implementation of the GEOTRACES program, the biogeochemical cycle and distribution of tellurium (Te) in marine environments are becoming increasing environmental concerns. In this study, the concentration o...With the implementation of the GEOTRACES program, the biogeochemical cycle and distribution of tellurium (Te) in marine environments are becoming increasing environmental concerns. In this study, the concentration of dissolved Te in the Changjiang (Yangtze) River estuary and nearby waters was determined in May 2009 by hydride-generation atomic fluorescence spectrometry to elucidate the abundance, dominant species, distribution, and relationship with environmental factors. Results show that: (1) dissolved Te was low owing to its low abundance in the Earth's crust, high insolubility in water, and strong affinity to particulate matter; (2) Te(IV) and Te(VI) predominated in surface water. Te(VI) was the dominant species in bottom water, and Te(IV) was the minor species; (3) Horizontally, resulting from low phytoplankton metabolism and the weak reduction from Te(VI) to Te(IV) in the shore, Te(IV) was concentrated in the central zone instead of the coastal region. However, Te(VI) was abundant near the mouth of the Changjiang River where the Changjiang water is diluted and in the area to the south where the Taiwan Warm Current invaded. In the adsorption-desorption process, Te(IV) was negatively related to suspended paniculate matter (SPM), indicating that it was adsorbed by particulate matter. While for Te(VI), the positive correlation with SPM suggested that it was desorbed from the solid phase. In the estuary, dissolved Te had a negative correlation to salinity. However, it deviated from the dilution line in high-salinity regions due to the invasion of the Taiwan Warm Current and the mineralization of organic matter. The relationship between Te(IV) and SPM nutrients indicated that it was more bioavailable and more related to phosphorus than to nitrogen. Progress in the field is slow and more research is needed to quantify the input of Te to the estuary and evaluate the biochemical role of organisms.展开更多
Pot-grown tomato plants (Lycopersicon esculentum Mill. cv. Maofen) was used to study the effects of three shading levels (0, 75% and 40%) for 8 days on dry matter partitioning, contents of nitrogen (N), phosphorus (P)...Pot-grown tomato plants (Lycopersicon esculentum Mill. cv. Maofen) was used to study the effects of three shading levels (0, 75% and 40%) for 8 days on dry matter partitioning, contents of nitrogen (N), phosphorus (P) and potassium (K) in leaves arid yield at three growth stages (early flowering (EF), peak flowering (PF) and later flowering (LF)). Shading reduced the dry weight of root and stem tissues at the EF and PF stages, but the 40% shading increased root dry weight and stem dry weight by 43.2% and 21.6%, respectively, at the LF stage. The influence of shading on the dry weight of leaves was very small at most growth stages. Shading had no effects on total leaf N, P and K contents at the EF and PF stages, showing that N, P and K absorption were regulated by the carbon assimilation at these two stages. The leaf N, P and K contents of 40% shaded plants at the LF stage were significantly increased. There were no obvious differences in leaf N and K contents between 75% and 40% shading treatments, but significant difference in leaf P contents was found between them at the LF stage. Shading significantly enhanced the fruit yield of 40% shaded tomato plants at the LF stage, but failed to affect the fruit yield of shaded plants at the EF stage. These showed that tomato could grow well and a better yield could be obtained if some moderate shading (i.e., 40% shading) was applied at the LF stage at summer midday.展开更多
The bioavailability of five divalent cationic heavy metals (Pb, Cd, Cu, Zn and Ni) in 10 superficial sediment samples from Baihua Lake was assessed based on the molar ratio of simultaneously extracted metals (SEMs...The bioavailability of five divalent cationic heavy metals (Pb, Cd, Cu, Zn and Ni) in 10 superficial sediment samples from Baihua Lake was assessed based on the molar ratio of simultaneously extracted metals (SEMs) to acid volatile sulfide (AVS). Atomic absorption spectrometry (AAS) and X-ray powder diffraction (XRD) were used to determine the heavy metal concentrations and examine the mineralogy of the crystalline phases, respectively. The AVS loadings in sediments from Baihua Lake ranged from 64.30 to 350.08 ~rnol/g (dry weight). The corresponding SEM levels for the sampling sites varied from 1.770 to 14.660 vrnol/g. The molar ratio of SEMs to AVS ranged from 0.014 to 0.084 with a mean value of 0.034. The XRD analysis also confirmed the presence of some metal sulfides in sediments from Baihua Lake. The SEMs/AVS ratios for all sampling sites were significantly lower than 1.0, indicating that AVS in the sediments was sufficient to bind the five heavy metals; thus, these heavy metals are currently not significantly bioavailable to benthic organisms. Comparing the SEMs results to published guideline values for metal toxicity to benthic organisms in sediments, however, suggests that Zn and Ni pose a risk at some sampling locations in Baihua Lake.展开更多
Objective:This study was aimed to research the feasibility of ATP-bioluminescence assay(ATP-TCA) guiding the treatment on recurrent non-small cell lung cancer(NSCLC) combined with malignant pleural effusion.Methods:We...Objective:This study was aimed to research the feasibility of ATP-bioluminescence assay(ATP-TCA) guiding the treatment on recurrent non-small cell lung cancer(NSCLC) combined with malignant pleural effusion.Methods:We collected 30 pleural fluid samples which were approved to be positive by cytology from recurrent NSCLC patients.These cells were cocultured with chemotherapy medicines,single agent or drugs combination.Five drug concentrations,two parallel holes were examined in vitro for 4 days,the results were measured by adding luciferase-fluorescein working system and luminescence analyzer.We applied chemotherapy medicines according to the results in vitro of ATP-TCA.Results:There were differences among drug sensitivities of individuals.All the samples could be evaluated.Effective single drugs included cisplatinum,mitomycin C,doxorubicin,and pemetrexed disodium;sensitive drugs in the combination therapy were gemcitabine plus cisplatin,vinorelbine plus cisplatin,paclitaxel plus cisplatin,docetaxel plus cisplatin,and mitomycin C,vindesine plus cisplatin,in which gemcitabine + cisplatin(GEM + DDP) in vitro was the most efficient program.Conclusion:ATP-TCA in vitro sensitivity assay is rapid,reliable,and simple to guide the treatment of recurrent NSCLC with malignant pleural effusion,and can help clinicians to make the individual chemotherapy program.展开更多
Abstract A real-time photo-realistic rendering algorithm of ocean color is introduced in the paper, which considers the impact of ocean bio-optical model. The ocean bio-optical model mainly involves the phytoplankton,...Abstract A real-time photo-realistic rendering algorithm of ocean color is introduced in the paper, which considers the impact of ocean bio-optical model. The ocean bio-optical model mainly involves the phytoplankton, colored dissolved organic material (CDOM), inorganic suspended particle, etc., which have different contributionsto absorption and scattering of light. We decompose the emergent light of the ocean surface into the reflected light from the sun and the sky, and the subsurface scattering light. We estab- lish an ocean surface transmission model based on ocean bidirectional reflectance distribution function (BRDF) and the Fresnel law, and this model's outputs would be the incident light parameters of subsurface scattering. Using ocean subsurface scattering algorithm combined with bio-optical model, we compute the scattering light emergent radiation in different directions. Then, we blend the re- flection of sunlight and sky light to implement the real-time ocean color rendering in graphics processing unit (GPU). Finally, we use two kinds of radiance reflectance calculated by Hydrolight radiative transfer model and our algorithm to validate the physical reality of our method, and the results show that our algorithm can achieve real-time highly realistic ocean color scenes.展开更多
The simple spectrophotometric method for the determination of esters has been developed. The procedure is based on the quantitative determination of ferric hydroxamate generated from the reaction of esters, hydroxylam...The simple spectrophotometric method for the determination of esters has been developed. The procedure is based on the quantitative determination of ferric hydroxamate generated from the reaction of esters, hydroxylamine hydrochloride in basic solution at 120℃, and ferric chloride. The formed complex was monitored through absorbance at 517 nm. The parameters affecting the absorbance value were explored for optimum analytical performance. The optimum conditions were 1.50 mL of 0.5 M hydroxylamine hydrochloride, 0.40 mL of 6 M sodium hydroxide, 1.00 mL of 3 M hydrochloric acid and 0.50 mL of 5 % ferric chloride. The method exhibits linear response up to 7.50% wt. and a detection limit of 0.23% wt. The linear range and working range were used at the same range 1.25 to 7.50% wt. The proposed method can be applied to biodiesel (B 100) for measuring the esters quantity in the percentage unit of biodiesel oil.展开更多
The purpose of this study was to explore influence of abiotic factors, such as high temperature, water deficiency and high solar radiation on the photomembrane of grapevine leaves. Grapevine leaves were collected from...The purpose of this study was to explore influence of abiotic factors, such as high temperature, water deficiency and high solar radiation on the photomembrane of grapevine leaves. Grapevine leaves were collected from variety Rkatsiteli (Vitis vinifera) and placed at a temperature of +45 ℃ and +55 ℃ for 5 rain, respectively. The relative volume of water in leaves was gradually reduced to 50%, and then leaves were irradiated with 6,000 pmol/m2.s of white light. Changes provoked by stressful abiotie factors were determined using rapid and delayed chlorophyll fluorescence methods. It was shown that value of variable component of chlorophyll fluorescence (Fv), intensity of electron transport between the photosystems (ETR), intensity of expended electrons in carboxylation (ETRn) and oxygenation (ETRp) and index of non-photochemical quenching (NPQ), allow studying molecular mechanisms of the impact of abiotic factors and the resulting damage degree. Based on delayed and rapid fluorescence data, it was demonstrated that temperature of +45 ℃ adversely affects oxygen production system and CO2 assimilation mechanisms, while at +55 ℃, the ETR decreases. Reduction of relative water volume in leaves up to 50%-55% leads to sharp reduction in ETR and inhibition of photosynthesis. In case of irradiation of leaves with high-intensity light of 6,000 μmol/m2.s, NPQ of light falling on a leaf increases, thus protecting photosynthesis apparatus from damage.展开更多
AIM: Anti-Saccharomyces anti-nuclear associated cerevisiae antibodies (ASCA), anti-neutrophil antibodies (NANA) and antibodies to exocrine pancreas (PAB), are serological tools for discriminating Crohn's disea...AIM: Anti-Saccharomyces anti-nuclear associated cerevisiae antibodies (ASCA), anti-neutrophil antibodies (NANA) and antibodies to exocrine pancreas (PAB), are serological tools for discriminating Crohn's disease (CrD) and ulcerative colitis (UC). Like CrD, coeliac disease (COD) is an inflammatory bowel disease (IBD) associated with (auto) antibodies. Performing a multicenter study we primarily aimed to determine the performance of ASCA, NANA and PAB tests for IBD diagnosis in children and adults, and secondarily to evaluate the prevalence of these markers in CoD. METHODS: Sera of 109 patients with CrD, 78 with UC, 45 with CoD and 50 healthy blood donors were retrospectively included. ASCA, NANA and PAB were detected by indirect immunofluorescence (IIF). RESULTS: ASCA+/NANA- profile displayed a positive predictive value of 94.2% for CrD. Detection of ASCA was correlated with a more severe clinical profile of CrD and treatment of the disease did not influence their serum levels. ASCA positivity was found in 37.9% of active CoD.PAB were found in 36.7% CrD and 13.3% CoD patients and were not correlated with clinical features of CrD, except with an early onset of the disease. Fifteen CrD patients were ASCA negative and PAB positive. CONCLUSION: ASCA and PAB detected by IIF are specific markers for CrD although their presence does not rule out a possible active CoD. The combination of ASCA, NANA and PAB tests improves the sensitivity of immunological markers for CrD. Repeating ASCA, NANA, and PAB testing during the course of CrD has no clinical value.展开更多
Biofilm is a community of bacteria, less susceptible to traditions treatments. Although photodynamic therapy (PDT) is a very effective way to microorganism inactivation, in biofilm it is not as efficient as it is in...Biofilm is a community of bacteria, less susceptible to traditions treatments. Although photodynamic therapy (PDT) is a very effective way to microorganism inactivation, in biofilm it is not as efficient as it is in planktonic bacteria cultures. The increment of an element to increase the effectiveness of PDT was our aim. Therefore, this in vitro study evaluates the susceptibility ofa biofilm formed by Streptococcus mutans on metallic surface of orthodontic accessories under the application of PDT with a surfactant. Samples obtained from blades of orthodontic bands (NiCr), where used as adhesion surface for the biofilm. They were treated with 1 mg/ml of curcumin, with 0.1% of sodium dodecyl sulfate and exposed to 30 J/cm^2 of light (455 nm). Eight experimental groups were studied, including the positive and negative controls. The results show that the group with PDT and surfactant had a significant decrease (p 〈 0.001) in viability. In this case, the reduction observed was of 5.6 log10 (CFU/ml) in comparison to the control group. We have shown that, even though the biofilm is very tough and complex structure, we are able to promote almost the complete inactivation ofS. mutans in systems similar to an orthodontic treated patient's mouth.展开更多
A precise zoom magnification is important for semiconductor industry and biomedical research. A novel measurement method is demonstrated for optical zoom magnification measurement in this paper. The magnification is o...A precise zoom magnification is important for semiconductor industry and biomedical research. A novel measurement method is demonstrated for optical zoom magnification measurement in this paper. The magnification is obtained by pattern correction between barcode image formed by optical zoom and reference image generated by an ideal optical model. Measurement accuracy which is better than 0.06% has been achieved for optical zoom magnification. Compared with traditional concept, the measurement results are only dependent on two line edges. The barcode correlation method can achieve higher accuracy and better robustness by using the information over the whole field of view.展开更多
Hens' eggs and corresponding feeds were sampled at commercial farms. The eggs were separated into egg yolk and egg white and freeze dried. After pressure digestion, total element contents of Ca, P, Mg, S, Na, Fe, Mn,...Hens' eggs and corresponding feeds were sampled at commercial farms. The eggs were separated into egg yolk and egg white and freeze dried. After pressure digestion, total element contents of Ca, P, Mg, S, Na, Fe, Mn, Zn, Sr, Cu and Ba were detected by ICP-OES in the eggs, whereas, Pb, Ni, Sb, Sn, AI, Cd, Cr, Mo and V were all or largely below the detection limits. In addition, iodine was done by ICP-MS and Se after ashing with Mg-nitrate by hydride-generation-AAS. There were significant accumulations of P, S, Se and I in the egg yolk versus feed levels, as well as S and Na in the egg white. Just a few correlations between concentrations in feed and egg white resp. egg yolk were detected, indicating regulation mechanisms by homeostasis. Strontium showed the strongest trends between feeds and egg white and egg yolk, whereas, there was none for calcium. Among the main elements in the feeds, sulfur had the strongest effects on the egg compositions, e.g., on iodine and iron in the yolk and on sodium in the white, some of them might be non-linear.展开更多
In this paper, two different diameter particles (TSP, PM10) were collected by TH-16A four-channels classification air sampler. The samples were treated by HNO3. Analysis of cadmium was carried out by hydride generat...In this paper, two different diameter particles (TSP, PM10) were collected by TH-16A four-channels classification air sampler. The samples were treated by HNO3. Analysis of cadmium was carried out by hydride generation atomic fluorescence spectrometry (HG-AFS) method, and distribution proportions of elements in four phases were calculated. This method was based on the reaction of cadmium with 1.5% (m/v) KBH4 solution and 0.5% KOH(m/v) solution to form the hydride gas in medium of 2% (v/v) HCl. The detection limit for cadmium as low as 0.008μg/L was obtained. The lineally correlation coefficient was 0.99992. The relative standard deviation (n=5, C=1.00μg/L) was 3.26%. The proposed method was applied for the determination of cadmium in atmosphere aerosol samples and the recoveries in the range of 95-102.2% were obtained. This method was simple, rapid, less matrix interference and high sensitivity.展开更多
基金School Fund of Xuzhou Institute of Technology (XKY200614)~~
文摘The aim of the study is to investigate the contents of trace element Se, Cd, Pb in three plants including burdock, ginkgol and garlic via graphite furnace atomic absorption and standard addition method. The results show that Se in burdock stem, skin and leaf are 32.40, 48.63, 38.10 μg/g, respectively; Cd in burdock stem, skin and leaf are 0. 160 0, 0. 300 0, 0. 140 0 μg/g, respectively; Cd in burdock stem, skin and leaf are 2. 020, 3. 960, 2. 410 μg/g, respectively. In the ginkgo and ginko leaf, Se contents are 17.63 and 16.91 μg/g, respectively ; for Cd are 0. 181 0 and 0.2020μg/g, respectively ; for Pb are 3. 572 and 4. 021 μg/g, respectively. In garlic, Se, Cd and Pb are 73. 900 0, 6. 900 0 and 0. 390 0, respectively. All the standard deviations of measured results are below 2.3%, recovery rate are from 99% to 101%.
基金supported funancialy by Qingdao Bio-temed Biomaterial Co.,Ltd.the National ‘Twelfth Five-Year’ Support Plan for Science&Technology of Chinia(2012BAI18B06)
文摘Chitosan, an excellent biomedical material, has received a widespread in vivo application. In contrast, its metabolism and distribution once being implanted were less documented. In this study, the pharmacokinetics and biodegradation of fluorescein isothiocyanate(FITC) labeled and muscle implantation administrated chitosan in rats were investigated with fluorescence spectrophotometry, histological assay and gel chromatography. After implantation, chitosan was degraded gradually during its distribution to diverse organs. Among the tested organs, liver and kidney were found to be the first two highest in chitosan content, which was followed by heart, brain and spleen. Urinary excretion was believed to be the major pathway of chitosan elimination, yet 80% of chitosan administered to rats was not trackable in their urine. This indicated that the majority of chitosan was degraded in tissues. In average, the molecular weight of the degradation products of chitosan in diverse organs and urine was found to be <65 k Da. This further confirmed the in vivo degradation of chitosan. Our findings provided new evidences for the intensive and safe application of chitosan as a biomedical material.
基金Supported No. 30530080 by the NSFC, and by Qingdao Bureau of Science and Technology (No. 04-2-NN-26).
文摘The author determined the occurrence of indole-3-acetic acid in sixteen Chinese marine algae collected from the east coast of China with fluorescence spectrophotometry (FS) and wheat coleop- tile bioanalysis methods (WCB). The concentration of indole-3-acetic acid (IAA) presented was from 1.1–46.9 ng/g Fw (fresh weight) with FS and 5.3–110.2 ng/g Fw with WCB. The results by the two meth- ods were in the orders of 10-3–103 ng/g Fw reported previously from multiple references.
基金Supported by the Key Projects of the National Natural Science Foundation of China(Nos.41076014,U0933005,41176035,40906022,41206029)
文摘We propose a bio-optical inversion model that retrieves the absorption contributions of phytoplankton and colored detrital matter(CDM),as well as the phytoplankton size classes(PSCs),from total minus water absorption spectra.The model is based on three-component separation of phytoplankton size structure and a genetic algorithm.The model performance was tested on two independent datasets(the NASA bio-Optical Marine Algorithm Dataset(NOMAD) and the northern South China Sea(NSCS) dataset).The relationships between the estimated and measured values were strongly linear,especially for aCDM(412),and the Root Mean Square Error(RMSE) of the CDM exponential slope(SCDM) was relatively low.Next,the inversion model was directly applied to in-situ total minus water absorption spectra determined by an underwater meter during a cruise in September 2008,to retrieve the phytoplankton size structure in the seawater.By comparing the measured and retrieved chlorophyll a concentrations,we demonstrated that total and size-specific chlorophyll a concentrations could be retrieved by the model with relatively high accuracy.Finally,we applied the bio-optical inversion model to investigate changes in phytoplankton size structure induced by an anti-cyclonic eddy in the NSCS.
基金Supported by the National Natural Science Foundation of China(21166003)the Doctoral Foundation of Ministry of Education of China(20114501110004)
文摘Pyrolusite reduction processes by three major biomass components cellulose,hemicelluloses and lignin,represented by CP,HP and LP,respectively,were investigated by thermogravimetric analyzer coupled with Fourier transform infrared spectrometry(TG-FTIR).The Sestak-Berggren(SB) equation was used to evaluate the kinetics of reduction processes.TG analysis reveals that the main reduction processes occur at 250-410 ℃,220-390 ℃,and 190-410 ℃ for CP,HP,and LP,respectively.FT-IR and XRD results indicate that various reducing volatiles(e.g.aldehydes,furans,ketones and alcohols) are produced from the pyrolysis with the three major components,which directly reduce MnO_2 in ore to MnO.The processes are described by the SB equation with three parameters(m,n,p).Their non-zero values suggest that pyrolusite reduction is controlled by the diffusion of reducing gaseous products through an ash/inert layer associated with minerals.The apparent activation energies for pyrolusite reduction by CP,HP and LP are 40.48,25.70 and 40.10 kJ·mol^(-1),respectively.
基金Supported by the National Basic Research Program of China(973 Program)(No.2011CB403602)the National Natural Science Foundation of China(No.41121064)
文摘With the implementation of the GEOTRACES program, the biogeochemical cycle and distribution of tellurium (Te) in marine environments are becoming increasing environmental concerns. In this study, the concentration of dissolved Te in the Changjiang (Yangtze) River estuary and nearby waters was determined in May 2009 by hydride-generation atomic fluorescence spectrometry to elucidate the abundance, dominant species, distribution, and relationship with environmental factors. Results show that: (1) dissolved Te was low owing to its low abundance in the Earth's crust, high insolubility in water, and strong affinity to particulate matter; (2) Te(IV) and Te(VI) predominated in surface water. Te(VI) was the dominant species in bottom water, and Te(IV) was the minor species; (3) Horizontally, resulting from low phytoplankton metabolism and the weak reduction from Te(VI) to Te(IV) in the shore, Te(IV) was concentrated in the central zone instead of the coastal region. However, Te(VI) was abundant near the mouth of the Changjiang River where the Changjiang water is diluted and in the area to the south where the Taiwan Warm Current invaded. In the adsorption-desorption process, Te(IV) was negatively related to suspended paniculate matter (SPM), indicating that it was adsorbed by particulate matter. While for Te(VI), the positive correlation with SPM suggested that it was desorbed from the solid phase. In the estuary, dissolved Te had a negative correlation to salinity. However, it deviated from the dilution line in high-salinity regions due to the invasion of the Taiwan Warm Current and the mineralization of organic matter. The relationship between Te(IV) and SPM nutrients indicated that it was more bioavailable and more related to phosphorus than to nitrogen. Progress in the field is slow and more research is needed to quantify the input of Te to the estuary and evaluate the biochemical role of organisms.
基金Project supported by the National Natural Science Foundation of China(No.40101005),the Provincial Natural Science Foundation of Shandong(No.Q2002E03)and the Provincial Education Committee of Shandong(No.J02L01).
文摘Pot-grown tomato plants (Lycopersicon esculentum Mill. cv. Maofen) was used to study the effects of three shading levels (0, 75% and 40%) for 8 days on dry matter partitioning, contents of nitrogen (N), phosphorus (P) and potassium (K) in leaves arid yield at three growth stages (early flowering (EF), peak flowering (PF) and later flowering (LF)). Shading reduced the dry weight of root and stem tissues at the EF and PF stages, but the 40% shading increased root dry weight and stem dry weight by 43.2% and 21.6%, respectively, at the LF stage. The influence of shading on the dry weight of leaves was very small at most growth stages. Shading had no effects on total leaf N, P and K contents at the EF and PF stages, showing that N, P and K absorption were regulated by the carbon assimilation at these two stages. The leaf N, P and K contents of 40% shaded plants at the LF stage were significantly increased. There were no obvious differences in leaf N and K contents between 75% and 40% shading treatments, but significant difference in leaf P contents was found between them at the LF stage. Shading significantly enhanced the fruit yield of 40% shaded tomato plants at the LF stage, but failed to affect the fruit yield of shaded plants at the EF stage. These showed that tomato could grow well and a better yield could be obtained if some moderate shading (i.e., 40% shading) was applied at the LF stage at summer midday.
基金Supported by the National Natural Science Foundation of China(No.20967003)the Project of the Government of Guiyang City(No.[2010]5-2)
文摘The bioavailability of five divalent cationic heavy metals (Pb, Cd, Cu, Zn and Ni) in 10 superficial sediment samples from Baihua Lake was assessed based on the molar ratio of simultaneously extracted metals (SEMs) to acid volatile sulfide (AVS). Atomic absorption spectrometry (AAS) and X-ray powder diffraction (XRD) were used to determine the heavy metal concentrations and examine the mineralogy of the crystalline phases, respectively. The AVS loadings in sediments from Baihua Lake ranged from 64.30 to 350.08 ~rnol/g (dry weight). The corresponding SEM levels for the sampling sites varied from 1.770 to 14.660 vrnol/g. The molar ratio of SEMs to AVS ranged from 0.014 to 0.084 with a mean value of 0.034. The XRD analysis also confirmed the presence of some metal sulfides in sediments from Baihua Lake. The SEMs/AVS ratios for all sampling sites were significantly lower than 1.0, indicating that AVS in the sediments was sufficient to bind the five heavy metals; thus, these heavy metals are currently not significantly bioavailable to benthic organisms. Comparing the SEMs results to published guideline values for metal toxicity to benthic organisms in sediments, however, suggests that Zn and Ni pose a risk at some sampling locations in Baihua Lake.
文摘Objective:This study was aimed to research the feasibility of ATP-bioluminescence assay(ATP-TCA) guiding the treatment on recurrent non-small cell lung cancer(NSCLC) combined with malignant pleural effusion.Methods:We collected 30 pleural fluid samples which were approved to be positive by cytology from recurrent NSCLC patients.These cells were cocultured with chemotherapy medicines,single agent or drugs combination.Five drug concentrations,two parallel holes were examined in vitro for 4 days,the results were measured by adding luciferase-fluorescein working system and luminescence analyzer.We applied chemotherapy medicines according to the results in vitro of ATP-TCA.Results:There were differences among drug sensitivities of individuals.All the samples could be evaluated.Effective single drugs included cisplatinum,mitomycin C,doxorubicin,and pemetrexed disodium;sensitive drugs in the combination therapy were gemcitabine plus cisplatin,vinorelbine plus cisplatin,paclitaxel plus cisplatin,docetaxel plus cisplatin,and mitomycin C,vindesine plus cisplatin,in which gemcitabine + cisplatin(GEM + DDP) in vitro was the most efficient program.Conclusion:ATP-TCA in vitro sensitivity assay is rapid,reliable,and simple to guide the treatment of recurrent NSCLC with malignant pleural effusion,and can help clinicians to make the individual chemotherapy program.
基金jointly supported by the International Cooperation and Exchange Projects of the National Natural Science Foundation of China (No.61361163001)the National Key Scientific Instrument and Equipment Development Projects of National Natural Science Foundation of China (No.41527901)the National High-Tech R&D Program (863 Program) (No.2013AA09A505)
文摘Abstract A real-time photo-realistic rendering algorithm of ocean color is introduced in the paper, which considers the impact of ocean bio-optical model. The ocean bio-optical model mainly involves the phytoplankton, colored dissolved organic material (CDOM), inorganic suspended particle, etc., which have different contributionsto absorption and scattering of light. We decompose the emergent light of the ocean surface into the reflected light from the sun and the sky, and the subsurface scattering light. We estab- lish an ocean surface transmission model based on ocean bidirectional reflectance distribution function (BRDF) and the Fresnel law, and this model's outputs would be the incident light parameters of subsurface scattering. Using ocean subsurface scattering algorithm combined with bio-optical model, we compute the scattering light emergent radiation in different directions. Then, we blend the re- flection of sunlight and sky light to implement the real-time ocean color rendering in graphics processing unit (GPU). Finally, we use two kinds of radiance reflectance calculated by Hydrolight radiative transfer model and our algorithm to validate the physical reality of our method, and the results show that our algorithm can achieve real-time highly realistic ocean color scenes.
文摘The simple spectrophotometric method for the determination of esters has been developed. The procedure is based on the quantitative determination of ferric hydroxamate generated from the reaction of esters, hydroxylamine hydrochloride in basic solution at 120℃, and ferric chloride. The formed complex was monitored through absorbance at 517 nm. The parameters affecting the absorbance value were explored for optimum analytical performance. The optimum conditions were 1.50 mL of 0.5 M hydroxylamine hydrochloride, 0.40 mL of 6 M sodium hydroxide, 1.00 mL of 3 M hydrochloric acid and 0.50 mL of 5 % ferric chloride. The method exhibits linear response up to 7.50% wt. and a detection limit of 0.23% wt. The linear range and working range were used at the same range 1.25 to 7.50% wt. The proposed method can be applied to biodiesel (B 100) for measuring the esters quantity in the percentage unit of biodiesel oil.
文摘The purpose of this study was to explore influence of abiotic factors, such as high temperature, water deficiency and high solar radiation on the photomembrane of grapevine leaves. Grapevine leaves were collected from variety Rkatsiteli (Vitis vinifera) and placed at a temperature of +45 ℃ and +55 ℃ for 5 rain, respectively. The relative volume of water in leaves was gradually reduced to 50%, and then leaves were irradiated with 6,000 pmol/m2.s of white light. Changes provoked by stressful abiotie factors were determined using rapid and delayed chlorophyll fluorescence methods. It was shown that value of variable component of chlorophyll fluorescence (Fv), intensity of electron transport between the photosystems (ETR), intensity of expended electrons in carboxylation (ETRn) and oxygenation (ETRp) and index of non-photochemical quenching (NPQ), allow studying molecular mechanisms of the impact of abiotic factors and the resulting damage degree. Based on delayed and rapid fluorescence data, it was demonstrated that temperature of +45 ℃ adversely affects oxygen production system and CO2 assimilation mechanisms, while at +55 ℃, the ETR decreases. Reduction of relative water volume in leaves up to 50%-55% leads to sharp reduction in ETR and inhibition of photosynthesis. In case of irradiation of leaves with high-intensity light of 6,000 μmol/m2.s, NPQ of light falling on a leaf increases, thus protecting photosynthesis apparatus from damage.
文摘AIM: Anti-Saccharomyces anti-nuclear associated cerevisiae antibodies (ASCA), anti-neutrophil antibodies (NANA) and antibodies to exocrine pancreas (PAB), are serological tools for discriminating Crohn's disease (CrD) and ulcerative colitis (UC). Like CrD, coeliac disease (COD) is an inflammatory bowel disease (IBD) associated with (auto) antibodies. Performing a multicenter study we primarily aimed to determine the performance of ASCA, NANA and PAB tests for IBD diagnosis in children and adults, and secondarily to evaluate the prevalence of these markers in CoD. METHODS: Sera of 109 patients with CrD, 78 with UC, 45 with CoD and 50 healthy blood donors were retrospectively included. ASCA, NANA and PAB were detected by indirect immunofluorescence (IIF). RESULTS: ASCA+/NANA- profile displayed a positive predictive value of 94.2% for CrD. Detection of ASCA was correlated with a more severe clinical profile of CrD and treatment of the disease did not influence their serum levels. ASCA positivity was found in 37.9% of active CoD.PAB were found in 36.7% CrD and 13.3% CoD patients and were not correlated with clinical features of CrD, except with an early onset of the disease. Fifteen CrD patients were ASCA negative and PAB positive. CONCLUSION: ASCA and PAB detected by IIF are specific markers for CrD although their presence does not rule out a possible active CoD. The combination of ASCA, NANA and PAB tests improves the sensitivity of immunological markers for CrD. Repeating ASCA, NANA, and PAB testing during the course of CrD has no clinical value.
文摘Biofilm is a community of bacteria, less susceptible to traditions treatments. Although photodynamic therapy (PDT) is a very effective way to microorganism inactivation, in biofilm it is not as efficient as it is in planktonic bacteria cultures. The increment of an element to increase the effectiveness of PDT was our aim. Therefore, this in vitro study evaluates the susceptibility ofa biofilm formed by Streptococcus mutans on metallic surface of orthodontic accessories under the application of PDT with a surfactant. Samples obtained from blades of orthodontic bands (NiCr), where used as adhesion surface for the biofilm. They were treated with 1 mg/ml of curcumin, with 0.1% of sodium dodecyl sulfate and exposed to 30 J/cm^2 of light (455 nm). Eight experimental groups were studied, including the positive and negative controls. The results show that the group with PDT and surfactant had a significant decrease (p 〈 0.001) in viability. In this case, the reduction observed was of 5.6 log10 (CFU/ml) in comparison to the control group. We have shown that, even though the biofilm is very tough and complex structure, we are able to promote almost the complete inactivation ofS. mutans in systems similar to an orthodontic treated patient's mouth.
文摘A precise zoom magnification is important for semiconductor industry and biomedical research. A novel measurement method is demonstrated for optical zoom magnification measurement in this paper. The magnification is obtained by pattern correction between barcode image formed by optical zoom and reference image generated by an ideal optical model. Measurement accuracy which is better than 0.06% has been achieved for optical zoom magnification. Compared with traditional concept, the measurement results are only dependent on two line edges. The barcode correlation method can achieve higher accuracy and better robustness by using the information over the whole field of view.
文摘Hens' eggs and corresponding feeds were sampled at commercial farms. The eggs were separated into egg yolk and egg white and freeze dried. After pressure digestion, total element contents of Ca, P, Mg, S, Na, Fe, Mn, Zn, Sr, Cu and Ba were detected by ICP-OES in the eggs, whereas, Pb, Ni, Sb, Sn, AI, Cd, Cr, Mo and V were all or largely below the detection limits. In addition, iodine was done by ICP-MS and Se after ashing with Mg-nitrate by hydride-generation-AAS. There were significant accumulations of P, S, Se and I in the egg yolk versus feed levels, as well as S and Na in the egg white. Just a few correlations between concentrations in feed and egg white resp. egg yolk were detected, indicating regulation mechanisms by homeostasis. Strontium showed the strongest trends between feeds and egg white and egg yolk, whereas, there was none for calcium. Among the main elements in the feeds, sulfur had the strongest effects on the egg compositions, e.g., on iodine and iron in the yolk and on sodium in the white, some of them might be non-linear.
文摘In this paper, two different diameter particles (TSP, PM10) were collected by TH-16A four-channels classification air sampler. The samples were treated by HNO3. Analysis of cadmium was carried out by hydride generation atomic fluorescence spectrometry (HG-AFS) method, and distribution proportions of elements in four phases were calculated. This method was based on the reaction of cadmium with 1.5% (m/v) KBH4 solution and 0.5% KOH(m/v) solution to form the hydride gas in medium of 2% (v/v) HCl. The detection limit for cadmium as low as 0.008μg/L was obtained. The lineally correlation coefficient was 0.99992. The relative standard deviation (n=5, C=1.00μg/L) was 3.26%. The proposed method was applied for the determination of cadmium in atmosphere aerosol samples and the recoveries in the range of 95-102.2% were obtained. This method was simple, rapid, less matrix interference and high sensitivity.