The time processes of photosynthetic induction responses to various irradiances in Korean pine (Pinus koraiensis) seedlings grown in open-light environments and in understory of forest were studied in an area near the...The time processes of photosynthetic induction responses to various irradiances in Korean pine (Pinus koraiensis) seedlings grown in open-light environments and in understory of forest were studied in an area near the Research Station of Changbai Mountain Forest Ecosystems, Jilin Province, China from July 15 to August 5, 1997. The results showed that at 200 靘olm-2s-1 photosynthetic photon flux density (PPFD) and 500 靘olm-2s-1 PPFD, the induction time for the photosynthetic rates of understory-grown seedlings to reach 50% and 90% steady-state net photosynthetic rates was longer than that of the open-grown seedlings. The induction responses of open-growth seedlings at 500 靘olm-2s-1 PPFD were slower than those at 200 靘olm-2s-1 PPFD, but it was the very reverse for understory-growth seedlings, which indicates that the photosynthetic induction times of Korean pine seedlings grown in the understory depended on the sunfleck intensity.展开更多
[Objective] The purpose was to study the optimum conditions of Pycnoporus sanguineus for producing ligninase. [Method] A strain of lignindegrading white-rot fungus was selected from 5 strains of collected fungi and it...[Objective] The purpose was to study the optimum conditions of Pycnoporus sanguineus for producing ligninase. [Method] A strain of lignindegrading white-rot fungus was selected from 5 strains of collected fungi and its ligninase production and the optimum conditions for producing ligninolytic enzyme were measured. [Result] It could produce two kinds of ligninase with good thermal stability. Different temperatures, carbon sources, nitrogen sources, acidities, as well as the additions of surfactant had distinct influence on the development of lignin-degrading enzymes of the fungus. The optimum condition was drawn out:38℃, pH = 4.5, 10.0 g/L glucose, 1.0 g/L tartaric acid ammonium. [Conclusion] The aim of research was to provide a basis for lignin degradation in practical production.展开更多
ln order to discuss the optimum seedling density of Toona ciliate, different seedling densities were studied. The results showed that seeding height and basal diameter decreased and quality of the seedlings declined w...ln order to discuss the optimum seedling density of Toona ciliate, different seedling densities were studied. The results showed that seeding height and basal diameter decreased and quality of the seedlings declined with the increase of seedling density. The reasonable density of seedlings is key to cultivate high-quality seedlings and achieve the best seedling efficiency. The optimum density was 30 plants/m2 for the first class seedlings of biennial seedlings, and the optimum density of l and ll seedlings for production afforestation was 40 plants/m2.展开更多
The organic carbon contents,carbon density and carbon storage of the soil in the Pinus koraiensis plantation ecosystem were investigated in Maoershan experimental forest farm,Shangzhi County,Heilongjiang,on the west s...The organic carbon contents,carbon density and carbon storage of the soil in the Pinus koraiensis plantation ecosystem were investigated in Maoershan experimental forest farm,Shangzhi County,Heilongjiang,on the west slope of the Zhangguangcai Mountains in northeastern China for providing data to evaluation of the carbon balance in forest ecosystem of northeastern China.These soil carbon indicators were measured in three forest types,pure P.koraiensis plantation,P.koraiensis and Betula platyphylla mixed forest,and the P.koraiensis and Quercus mongolica mixed forest.The soil carbon pool consisted of four compartments,namely L layer,F layer,H layer and B layer.With variance analysis,we found that both organic carbon content and carbon density of the soil were significantly affected by forest types,soil compartments and slope positions.The highest soil carbon density(278.63 Mg·ha^-1).was observed in the mixed forest of P.koraiensis and Q.mongolica.The B layer had the highest carbon density(212.28 Mg·ha^-1) among all the soil compartments.In terms of slope position,the highest soil carbon density(394.18 Mg·ha^-1) presented in the low slope.Besides,soil carbon content and carbon density had a marked change with the organic matter content and vertical depth of the soil in each compartment.The results of this study implied that in the temperate humid region,the mixed ecosystem of regional Pinus koraiensis plantations and natural forest had relatively high carbon storage capability.展开更多
Four-, six-, and eight-membered ring silica nanotubes at temperatures from 300 K to 1600 K are relaxed by classical molecular dynamics simulations with three potential models. The simulation results indicate that the ...Four-, six-, and eight-membered ring silica nanotubes at temperatures from 300 K to 1600 K are relaxed by classical molecular dynamics simulations with three potential models. The simulation results indicate that the stability of the end rings of the three silica nanotubes gradually decreases with increase in temperature. The validity of the vibrational features of silica nanotubes is shown by the vibrational density of states. Infrared spectra on the silica nanotubes under different temperatures are investigated. A detailed assignment of each spectral peak to the corresponding vibrational mode of the three nanotubes has been addressed. The results are in good agreement with the other theoretical and experimental展开更多
Objective:To detect the reliability of near-infrared parameters of blood oxygen of mammary gland phyma from the microvessel density of tumor.Methods:181 cases of mammary gland phyma who had accepted the examination of...Objective:To detect the reliability of near-infrared parameters of blood oxygen of mammary gland phyma from the microvessel density of tumor.Methods:181 cases of mammary gland phyma who had accepted the examination of the near-infrared TBO-I dual-wave length mammary gland phyma detector were classified by near-infrared parameters of blood oxygen,and were performed the pathologic examination to ascertain whether the tumor was benign or malignant.Among these cases,intratumoral microvessel density of 20 cases of malignant phyma and 20 cases of benign phyma were confirmed by S-P immunohistochemical method,then the relationship between near-infrared parameters and microvessel density were analyzed by medical statistics.Results:(1)The microvessel density and blood concentration of 28 cases of the"high blood" tumor were 24.56±8.110 and 1.891±0.850 respectively.The microvessel density and blood concentration of 12 cases of the"low blood"tumor were 17.98±8.729 and 0.698±0.283 respectively.There was significant difference between the"high blood"and"low blood"tumors(P<0.05).(2)The intratumoral microvessel density and blood concentration were linearly correlated respectively,and the linear correlation coefficient r=0.4208(P<0.05)in 40 cases of mammary gland phyma. Conclusion:The intratumoral microvessel density and blood concentration of benign or malignant mammary gland phyma were linearly correlated.Blood concentration(one of near-infrared parameters)is reliable to be used as diagnosis criterion of malignant mammary gland phyma.展开更多
The IR absorption, visible excited normal Raman, and UV-excited near-resonant Raman (UVRR) spectra of 1,1'-binaphthyl-2,2'-diamine (BINAM) were measured and analyzed. Density functional theory calculations were ...The IR absorption, visible excited normal Raman, and UV-excited near-resonant Raman (UVRR) spectra of 1,1'-binaphthyl-2,2'-diamine (BINAM) were measured and analyzed. Density functional theory calculations were carried out to investigate its vibrational frequencies, infrared absorption, normal Raman, and near-resonance Raman intensities. The observed Raman and IR bands of BINAM were assigned with respect to the local vibrations of substituted 2-naphthylamine. Several Raman bands of BINAM were found selectively enhanced in the UVRR in comparison with the normal Raman spectrum. Possible excited state geometry distortion was discussed based on the resonance Raman intensity analysis.展开更多
Light illumination has been widely used to promote activity and selectivity of traditional thermal catalysts. Nevertheless, the role of light irradiation during catalytic reactions is not well understood. In this work...Light illumination has been widely used to promote activity and selectivity of traditional thermal catalysts. Nevertheless, the role of light irradiation during catalytic reactions is not well understood. In this work, Pt/Al2 O3 prepared by wet impregnation was used for photothermal CO2 hydrogenation, and it showed a photothermal effect. Hence, operando diffuse reflectance infrared Fourier-transform spectroscopy and density functional theory calculations were conducted on Pt/Al2 O3 to gain insights into the reaction mechanism. The results indicated that CO desorption from Pt sites including step sites(Ptstep) or/and terrace site(Ptterrace) is an important step during CO2 hydrogenation to free the active Pt sites. Notably, visible light illumination and temperature affected the CO desorption in different ways. The calculated adsorption energy of CO on Ptstep and Ptterrace sites was-1.24 and-1.43 e V, respectively. Hence, CO is more strongly bound to the Ptstep sites. During heating in the dark, CO preferentially desorbs from the Ptterrace site. However, the additional light irradiation facilitates transfer of CO from the Ptstep to Ptterrace sites and its subsequent desorption from the Ptterrace sites, thus promoting the CO2 hydrogenation.展开更多
Two field trials were clone to evaluate the effects of plant density on the growth, development and yield of safflower. The results showed that plant density and season of growth had significant (P ≤ 0.01) effects ...Two field trials were clone to evaluate the effects of plant density on the growth, development and yield of safflower. The results showed that plant density and season of growth had significant (P ≤ 0.01) effects on growth, development, yield components, yield and oil content of safflower. Increasing safflower plant density from 100,000 to 250,000 plants ha^- significantly reduced plant height (13.2%-21.3%), branch number plant^-1 (37%-54.7%), leaf number plant^-1 (39%-39.2%), leaf area (19.5%-53%), plant spread (39.6%-54.4%), root length (28.1%-54.4%), plant biomass (17%-50%), capitula size (12%-12.7%), capitula number plant^-1 (39.5%-50.5%), seed number capitula~ (39%-45%), capitula weight (3.3%-3.6%), seed yield (67.9%-69.8%) and seed oil content (14.7%-20.8%). The reduction in vegetative growth, yield components, yield and oil content of safflower due to increased plant density was attributed to inter and intra-plant competition for light, nutrients and water necessary for growth and development. The differences between winter and summer grown safflower were attributed to difference in day and night temperature (DIF) and the average daily temperature which were optimum for safflower growth in winter. It was concluded that under Botswana conditions or in semi-arid areas, safflower should be planted at 50 cm × 20 cm or wider in order to maximize yield and oil content and allow the plants to express their maximum genetic potential.展开更多
The distribution patterns of mangrove Bruguiera gymnorrhiza population s in southern China are analyzed using the box-counting method of fractal theory. The patterns of B. gymnorrhiza populations could be thought of a...The distribution patterns of mangrove Bruguiera gymnorrhiza population s in southern China are analyzed using the box-counting method of fractal theory. The patterns of B. gymnorrhiza populations could be thought of as fractals as they exhibit self-similarity within the range of scale considered. Their fractal dimensions are not integer but fractional, ranging from 1.04 to 1.51. The unoccupied dimensions change from 0.49 to 0.96. The combined conditions of population density, pattern type and aggregation intensity together influence the values of fractal dimensions of patterns. The box counting is a useful and efficient method to investigate the complexity of patterns. Fractal dimension may be a most desirable and appropriate index for quantifying the horizontal spatial microstructure and fractal behaviors of patterns over a certain range of scales.展开更多
Urea L-malic acid, a new second order nonlinear optical crystal, was studied using density functional theory (DFT). PBEPBE/6-31+G(d,p) method, the optimal method for comparing the results from the several DFT met...Urea L-malic acid, a new second order nonlinear optical crystal, was studied using density functional theory (DFT). PBEPBE/6-31+G(d,p) method, the optimal method for comparing the results from the several DFT methods, was chosen to study the molecular structure. Infrared and ultraviolet-visible spectra were obtained and compared with experiments. The ultraviolet-visible spectrum was also analyzed by the molecular orbital population. The geometries, and the infrared and ultraviolet-visible spectra in water were studied using DFT methods in combination with the polarized continuum model to predict the perturbations by the solvent effect.展开更多
The carbon chain cations, HC2nO+(n=3-6) are produced via a pulsed laser vaporization supersonic expansion ion source in the gas phase. Their infrared spectra are measured via mass-selected infrared photodissociation s...The carbon chain cations, HC2nO+(n=3-6) are produced via a pulsed laser vaporization supersonic expansion ion source in the gas phase. Their infrared spectra are measured via mass-selected infrared photodissociation spectroscopy of the CO “tagged”[HC2nO·CO]+ cation complexes in 1600-3500 cm-1 frequency range. The geometric and electronic structures of the [HC2nO·CO]+ complexes and the core HC2nO+(n=3-6) cations are determined with the aid of density functional theory calculations. These HC2nO+(n=3-6) ions are identified to be linear carbon chain derivatives terminally capped by hydrogen and oxygen. The triplet ground states are 10-15 kcal/mol lower in energy than the singlet states, indicating cumulene-like carbon chain structures.展开更多
Reaction of laser ablated zinc and cadmium atoms with SO2 molecules was studied by low temperature matrix isolation infrared spectroscopy. Cyclic M(SO2) and anion M(SO2)-(M=Zn, Cd) were produced in excess argon ...Reaction of laser ablated zinc and cadmium atoms with SO2 molecules was studied by low temperature matrix isolation infrared spectroscopy. Cyclic M(SO2) and anion M(SO2)-(M=Zn, Cd) were produced in excess argon and neon, which were identified by 34SO2 and S18O2 isotopic substitutions. The observed infrared spectra and molecular structures were confirmed by density functional theoretical calculations. Natural charge distributions indicated significant electron transfer from s orbitals of zinc or cadmium metal atom to S02 ligand and cyclic M(SO2) complexes favored "ion pair" M+(SO2)-formation, which were trapped in low temperature matrices. In addition Zn-O or Cd-O bond in M(SO2) exhibited strong polarized covalent character. Reaction of Hg atom with SO2 was also investigated, but no reaction product was observed, due to the relativistic effect that resulted in the contraction of 6s valence shell and high ionization potential of Hg atom.展开更多
An experiment on retail film packaging system was conducted to compare the atmospheric composition within sealed packs containing rambutan fruits. This research was done in order to study the effect of packaging films...An experiment on retail film packaging system was conducted to compare the atmospheric composition within sealed packs containing rambutan fruits. This research was done in order to study the effect of packaging films with different permeability on the some of physicochemical properties of rambutan during storage at 10℃. The films used were 0.090 mm low density polyethylene (LDPE), 0.040 mm polyprophylene and 0.057 mm LDPE compared unwrapped fruits. Fruits were evaluated every 5 days for changes in moisture content, total sugars, vitamin C, hardness and color. Unwrapped rambutan had severe browning after 10 days. Sealed packages especially the LDPE had delayed the development of the browning for 20 days of storage and had the lowest weight loss.展开更多
The objective of this investigation was to study whether it is possible to determine the air tightness of covered slurry storage tanks using tracer gas technique by injection of sulphur hexafluoride (SF6) and measur...The objective of this investigation was to study whether it is possible to determine the air tightness of covered slurry storage tanks using tracer gas technique by injection of sulphur hexafluoride (SF6) and measurements of the decay in gas concentrations with an infrared spectrophotometer in the air space above the slurry. By measuring the decay in concentration of injected tracer gas at different occasions, the air exchange rate was determined. Three different types of coverings were studied namely; wooden roof, plastic tent and concrete roof.展开更多
Objective To examine target attainment of lipid-lowering, antihypenensive and antidiabetic treatment in the elderly in a specialist set- ting of a University Hospital in Greece. Methods This was a retrospective study ...Objective To examine target attainment of lipid-lowering, antihypenensive and antidiabetic treatment in the elderly in a specialist set- ting of a University Hospital in Greece. Methods This was a retrospective study including consecutive subjects 〉 65 years old (n = 465) with a follow-up 〉 3 years. Low-density lipoprotein cholesterol (LDL-C), blood pressure (BP) and glycated hemoglobin (HbAlc) goal achievement were recorded according to European Society of Cardiology/European Atherosclerosis Society (ESC/EAS), European Society of Hypertension (ESH)/ESC and European Association for the Study of Diabetes (EASD) guidelines. Results The LDL-C targets were attained by 27~,4, 48% and 62% of very high, high and moderate risk patients, respectively. Those receiving statin + ezetimibe achieved higher rates of LDL-C goal achievement compared with those receiving statin monotherapy (48% vs. 33%, P 〈 0.05). Of the diabetic sub- jects, 71% had BP 〈 140/85 mmHg, while 78% of those without diabetes had BP 〈 140/90 mmHg. A higher proportion of the non-diabetic individuals (86%) had BP 〈 150/90 mmHg. Also, a higher proportion of those with diabetes had HbAlc 〈 8% rather than 〈 7% (88% and 47%, respectively). Of note, almost one out of three non-diabetic individuals and one out of ten diabetic individuals had achieved all three treatment targets. Conclusions Even in a specialist setting of a University Hospital, a high proportion of the elderly remain at suboptimal LDL-C, BP and HbAlc levels. The use of drug combinations could improve multifactorial treatment target attainment, while less strict tar- gets could be more easily achieved in this population.展开更多
Background The diagnosis of metabolic syndrome indicates a clustering of metabolic imbalances which in sum have been recognized as a major predictor of cardiovascular and all-cause mortality. The aim of this study was...Background The diagnosis of metabolic syndrome indicates a clustering of metabolic imbalances which in sum have been recognized as a major predictor of cardiovascular and all-cause mortality. The aim of this study was to assess the level of under-pharmacy and poly-pbarmacy and its prognostic impact in elderly patients with metabolic syndrome. Methods Retrospective chart-review at a tertiary medical center, of 324 patients greater than 65 years of age who met the International Diabetes Foundation criteria for metabolic syndrome diagnosis [Body Mass Index (BMI) 〉 30 kg/m2, diagnosis of type 2 diabetes, hypertension, and dyslipidemia]. Results There were 60 (18.5%) patients in the low (〈 5) medication burden group, 159 (49.1%) in the medium (〉 5 and 〈 10) medication burden group, and 105 (32.4%) in the high (〉 10) medication burden group. At baseline, the groups differed only by systolic blood pressure. At two years follow-up, the medium group had significantly better improvement in high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), HbAlc, and systolic blood pressure compared to the low medication burden group and significantly better improvement in triglycerides, Haemoglobin Alc (HbAlc) and systolic blood pressure compared to the high medication group. Decrease in HDL-C was the only variable associated with strokes. High medication burden predicted hospitalization burden. The number of anti-hypertensives, history of tobacco use, low and high medication burdens and decrease in HDL-C were all associated with death. Conclusions Both poly-pharmacy and under-pharmacy are associated with a decreased therapeutic benefit among patients with metabolic syndrome in terms of important laboratory measurements as well as clinical outcomes such as myocardial infarctions, hospitalization, and death.展开更多
Despite red phosphorous(P)-based anodes hold great promise for advanced lithium-ion batteries due to their high theoretical capacity, their practical application is hindered by poor electronic conductivity and drastic...Despite red phosphorous(P)-based anodes hold great promise for advanced lithium-ion batteries due to their high theoretical capacity, their practical application is hindered by poor electronic conductivity and drastic volume changes during charge-discharge processes. In order to tackle these issues, herein, a facile grinding method was developed to embed sub-micro-and nano-sized red P particles in N,P-codoped hierarchical porous carbon(NPHPC). Such a unique structure enables P@NPHPC long-cyclic stability(1120 mAh g^-1 after 100 cycles at 100 mA g^-1) and superior rate performance(248 mA h g^-1 at 6400 mA g^-1). It is believed that our method holds great potential in scalable synthesis of P@carbon composites for future practical applications.展开更多
文摘The time processes of photosynthetic induction responses to various irradiances in Korean pine (Pinus koraiensis) seedlings grown in open-light environments and in understory of forest were studied in an area near the Research Station of Changbai Mountain Forest Ecosystems, Jilin Province, China from July 15 to August 5, 1997. The results showed that at 200 靘olm-2s-1 photosynthetic photon flux density (PPFD) and 500 靘olm-2s-1 PPFD, the induction time for the photosynthetic rates of understory-grown seedlings to reach 50% and 90% steady-state net photosynthetic rates was longer than that of the open-grown seedlings. The induction responses of open-growth seedlings at 500 靘olm-2s-1 PPFD were slower than those at 200 靘olm-2s-1 PPFD, but it was the very reverse for understory-growth seedlings, which indicates that the photosynthetic induction times of Korean pine seedlings grown in the understory depended on the sunfleck intensity.
文摘[Objective] The purpose was to study the optimum conditions of Pycnoporus sanguineus for producing ligninase. [Method] A strain of lignindegrading white-rot fungus was selected from 5 strains of collected fungi and its ligninase production and the optimum conditions for producing ligninolytic enzyme were measured. [Result] It could produce two kinds of ligninase with good thermal stability. Different temperatures, carbon sources, nitrogen sources, acidities, as well as the additions of surfactant had distinct influence on the development of lignin-degrading enzymes of the fungus. The optimum condition was drawn out:38℃, pH = 4.5, 10.0 g/L glucose, 1.0 g/L tartaric acid ammonium. [Conclusion] The aim of research was to provide a basis for lignin degradation in practical production.
基金Supported by Forestry Science and Technology Planning Program(XLK201406)~~
文摘ln order to discuss the optimum seedling density of Toona ciliate, different seedling densities were studied. The results showed that seeding height and basal diameter decreased and quality of the seedlings declined with the increase of seedling density. The reasonable density of seedlings is key to cultivate high-quality seedlings and achieve the best seedling efficiency. The optimum density was 30 plants/m2 for the first class seedlings of biennial seedlings, and the optimum density of l and ll seedlings for production afforestation was 40 plants/m2.
基金supported by National Technology Support Project (2008BAD95B10-6)
文摘The organic carbon contents,carbon density and carbon storage of the soil in the Pinus koraiensis plantation ecosystem were investigated in Maoershan experimental forest farm,Shangzhi County,Heilongjiang,on the west slope of the Zhangguangcai Mountains in northeastern China for providing data to evaluation of the carbon balance in forest ecosystem of northeastern China.These soil carbon indicators were measured in three forest types,pure P.koraiensis plantation,P.koraiensis and Betula platyphylla mixed forest,and the P.koraiensis and Quercus mongolica mixed forest.The soil carbon pool consisted of four compartments,namely L layer,F layer,H layer and B layer.With variance analysis,we found that both organic carbon content and carbon density of the soil were significantly affected by forest types,soil compartments and slope positions.The highest soil carbon density(278.63 Mg·ha^-1).was observed in the mixed forest of P.koraiensis and Q.mongolica.The B layer had the highest carbon density(212.28 Mg·ha^-1) among all the soil compartments.In terms of slope position,the highest soil carbon density(394.18 Mg·ha^-1) presented in the low slope.Besides,soil carbon content and carbon density had a marked change with the organic matter content and vertical depth of the soil in each compartment.The results of this study implied that in the temperate humid region,the mixed ecosystem of regional Pinus koraiensis plantations and natural forest had relatively high carbon storage capability.
文摘Four-, six-, and eight-membered ring silica nanotubes at temperatures from 300 K to 1600 K are relaxed by classical molecular dynamics simulations with three potential models. The simulation results indicate that the stability of the end rings of the three silica nanotubes gradually decreases with increase in temperature. The validity of the vibrational features of silica nanotubes is shown by the vibrational density of states. Infrared spectra on the silica nanotubes under different temperatures are investigated. A detailed assignment of each spectral peak to the corresponding vibrational mode of the three nanotubes has been addressed. The results are in good agreement with the other theoretical and experimental
文摘Objective:To detect the reliability of near-infrared parameters of blood oxygen of mammary gland phyma from the microvessel density of tumor.Methods:181 cases of mammary gland phyma who had accepted the examination of the near-infrared TBO-I dual-wave length mammary gland phyma detector were classified by near-infrared parameters of blood oxygen,and were performed the pathologic examination to ascertain whether the tumor was benign or malignant.Among these cases,intratumoral microvessel density of 20 cases of malignant phyma and 20 cases of benign phyma were confirmed by S-P immunohistochemical method,then the relationship between near-infrared parameters and microvessel density were analyzed by medical statistics.Results:(1)The microvessel density and blood concentration of 28 cases of the"high blood" tumor were 24.56±8.110 and 1.891±0.850 respectively.The microvessel density and blood concentration of 12 cases of the"low blood"tumor were 17.98±8.729 and 0.698±0.283 respectively.There was significant difference between the"high blood"and"low blood"tumors(P<0.05).(2)The intratumoral microvessel density and blood concentration were linearly correlated respectively,and the linear correlation coefficient r=0.4208(P<0.05)in 40 cases of mammary gland phyma. Conclusion:The intratumoral microvessel density and blood concentration of benign or malignant mammary gland phyma were linearly correlated.Blood concentration(one of near-infrared parameters)is reliable to be used as diagnosis criterion of malignant mammary gland phyma.
基金This work was supported by the National Natural Science Foundation of China (No.21273211, No.21573208), USTC-NSRL Association Foundation (No.NSRLLHJJ(14-15-012), and the Supercomputation Center of USTC.
文摘The IR absorption, visible excited normal Raman, and UV-excited near-resonant Raman (UVRR) spectra of 1,1'-binaphthyl-2,2'-diamine (BINAM) were measured and analyzed. Density functional theory calculations were carried out to investigate its vibrational frequencies, infrared absorption, normal Raman, and near-resonance Raman intensities. The observed Raman and IR bands of BINAM were assigned with respect to the local vibrations of substituted 2-naphthylamine. Several Raman bands of BINAM were found selectively enhanced in the UVRR in comparison with the normal Raman spectrum. Possible excited state geometry distortion was discussed based on the resonance Raman intensity analysis.
基金supported by the National Natural Science Foundation of China(U1862111,U1232119)Sichuan Provincial International Cooperation Project(2017HH0030)the Innovative Research Team of Sichuan Province(2016TD0011)~~
文摘Light illumination has been widely used to promote activity and selectivity of traditional thermal catalysts. Nevertheless, the role of light irradiation during catalytic reactions is not well understood. In this work, Pt/Al2 O3 prepared by wet impregnation was used for photothermal CO2 hydrogenation, and it showed a photothermal effect. Hence, operando diffuse reflectance infrared Fourier-transform spectroscopy and density functional theory calculations were conducted on Pt/Al2 O3 to gain insights into the reaction mechanism. The results indicated that CO desorption from Pt sites including step sites(Ptstep) or/and terrace site(Ptterrace) is an important step during CO2 hydrogenation to free the active Pt sites. Notably, visible light illumination and temperature affected the CO desorption in different ways. The calculated adsorption energy of CO on Ptstep and Ptterrace sites was-1.24 and-1.43 e V, respectively. Hence, CO is more strongly bound to the Ptstep sites. During heating in the dark, CO preferentially desorbs from the Ptterrace site. However, the additional light irradiation facilitates transfer of CO from the Ptstep to Ptterrace sites and its subsequent desorption from the Ptterrace sites, thus promoting the CO2 hydrogenation.
文摘Two field trials were clone to evaluate the effects of plant density on the growth, development and yield of safflower. The results showed that plant density and season of growth had significant (P ≤ 0.01) effects on growth, development, yield components, yield and oil content of safflower. Increasing safflower plant density from 100,000 to 250,000 plants ha^- significantly reduced plant height (13.2%-21.3%), branch number plant^-1 (37%-54.7%), leaf number plant^-1 (39%-39.2%), leaf area (19.5%-53%), plant spread (39.6%-54.4%), root length (28.1%-54.4%), plant biomass (17%-50%), capitula size (12%-12.7%), capitula number plant^-1 (39.5%-50.5%), seed number capitula~ (39%-45%), capitula weight (3.3%-3.6%), seed yield (67.9%-69.8%) and seed oil content (14.7%-20.8%). The reduction in vegetative growth, yield components, yield and oil content of safflower due to increased plant density was attributed to inter and intra-plant competition for light, nutrients and water necessary for growth and development. The differences between winter and summer grown safflower were attributed to difference in day and night temperature (DIF) and the average daily temperature which were optimum for safflower growth in winter. It was concluded that under Botswana conditions or in semi-arid areas, safflower should be planted at 50 cm × 20 cm or wider in order to maximize yield and oil content and allow the plants to express their maximum genetic potential.
基金The paper is supported by grants from the NSFC (No. 39825106 and 39860023).
文摘The distribution patterns of mangrove Bruguiera gymnorrhiza population s in southern China are analyzed using the box-counting method of fractal theory. The patterns of B. gymnorrhiza populations could be thought of as fractals as they exhibit self-similarity within the range of scale considered. Their fractal dimensions are not integer but fractional, ranging from 1.04 to 1.51. The unoccupied dimensions change from 0.49 to 0.96. The combined conditions of population density, pattern type and aggregation intensity together influence the values of fractal dimensions of patterns. The box counting is a useful and efficient method to investigate the complexity of patterns. Fractal dimension may be a most desirable and appropriate index for quantifying the horizontal spatial microstructure and fractal behaviors of patterns over a certain range of scales.
基金ACKNOWLEDGMENTS This work was supported by the Program for New Century Excellent Talents in University, the Science and Technology Foundation for Young Scholars in Sichuan Province, and the National Natural Science Foundation of China (No.10774104).
文摘Urea L-malic acid, a new second order nonlinear optical crystal, was studied using density functional theory (DFT). PBEPBE/6-31+G(d,p) method, the optimal method for comparing the results from the several DFT methods, was chosen to study the molecular structure. Infrared and ultraviolet-visible spectra were obtained and compared with experiments. The ultraviolet-visible spectrum was also analyzed by the molecular orbital population. The geometries, and the infrared and ultraviolet-visible spectra in water were studied using DFT methods in combination with the polarized continuum model to predict the perturbations by the solvent effect.
基金supported by the National Natural Science Foundation of China (No.21688102, No.21433005, and No.21573047)
文摘The carbon chain cations, HC2nO+(n=3-6) are produced via a pulsed laser vaporization supersonic expansion ion source in the gas phase. Their infrared spectra are measured via mass-selected infrared photodissociation spectroscopy of the CO “tagged”[HC2nO·CO]+ cation complexes in 1600-3500 cm-1 frequency range. The geometric and electronic structures of the [HC2nO·CO]+ complexes and the core HC2nO+(n=3-6) cations are determined with the aid of density functional theory calculations. These HC2nO+(n=3-6) ions are identified to be linear carbon chain derivatives terminally capped by hydrogen and oxygen. The triplet ground states are 10-15 kcal/mol lower in energy than the singlet states, indicating cumulene-like carbon chain structures.
文摘Reaction of laser ablated zinc and cadmium atoms with SO2 molecules was studied by low temperature matrix isolation infrared spectroscopy. Cyclic M(SO2) and anion M(SO2)-(M=Zn, Cd) were produced in excess argon and neon, which were identified by 34SO2 and S18O2 isotopic substitutions. The observed infrared spectra and molecular structures were confirmed by density functional theoretical calculations. Natural charge distributions indicated significant electron transfer from s orbitals of zinc or cadmium metal atom to S02 ligand and cyclic M(SO2) complexes favored "ion pair" M+(SO2)-formation, which were trapped in low temperature matrices. In addition Zn-O or Cd-O bond in M(SO2) exhibited strong polarized covalent character. Reaction of Hg atom with SO2 was also investigated, but no reaction product was observed, due to the relativistic effect that resulted in the contraction of 6s valence shell and high ionization potential of Hg atom.
文摘An experiment on retail film packaging system was conducted to compare the atmospheric composition within sealed packs containing rambutan fruits. This research was done in order to study the effect of packaging films with different permeability on the some of physicochemical properties of rambutan during storage at 10℃. The films used were 0.090 mm low density polyethylene (LDPE), 0.040 mm polyprophylene and 0.057 mm LDPE compared unwrapped fruits. Fruits were evaluated every 5 days for changes in moisture content, total sugars, vitamin C, hardness and color. Unwrapped rambutan had severe browning after 10 days. Sealed packages especially the LDPE had delayed the development of the browning for 20 days of storage and had the lowest weight loss.
文摘The objective of this investigation was to study whether it is possible to determine the air tightness of covered slurry storage tanks using tracer gas technique by injection of sulphur hexafluoride (SF6) and measurements of the decay in gas concentrations with an infrared spectrophotometer in the air space above the slurry. By measuring the decay in concentration of injected tracer gas at different occasions, the air exchange rate was determined. Three different types of coverings were studied namely; wooden roof, plastic tent and concrete roof.
文摘Objective To examine target attainment of lipid-lowering, antihypenensive and antidiabetic treatment in the elderly in a specialist set- ting of a University Hospital in Greece. Methods This was a retrospective study including consecutive subjects 〉 65 years old (n = 465) with a follow-up 〉 3 years. Low-density lipoprotein cholesterol (LDL-C), blood pressure (BP) and glycated hemoglobin (HbAlc) goal achievement were recorded according to European Society of Cardiology/European Atherosclerosis Society (ESC/EAS), European Society of Hypertension (ESH)/ESC and European Association for the Study of Diabetes (EASD) guidelines. Results The LDL-C targets were attained by 27~,4, 48% and 62% of very high, high and moderate risk patients, respectively. Those receiving statin + ezetimibe achieved higher rates of LDL-C goal achievement compared with those receiving statin monotherapy (48% vs. 33%, P 〈 0.05). Of the diabetic sub- jects, 71% had BP 〈 140/85 mmHg, while 78% of those without diabetes had BP 〈 140/90 mmHg. A higher proportion of the non-diabetic individuals (86%) had BP 〈 150/90 mmHg. Also, a higher proportion of those with diabetes had HbAlc 〈 8% rather than 〈 7% (88% and 47%, respectively). Of note, almost one out of three non-diabetic individuals and one out of ten diabetic individuals had achieved all three treatment targets. Conclusions Even in a specialist setting of a University Hospital, a high proportion of the elderly remain at suboptimal LDL-C, BP and HbAlc levels. The use of drug combinations could improve multifactorial treatment target attainment, while less strict tar- gets could be more easily achieved in this population.
文摘Background The diagnosis of metabolic syndrome indicates a clustering of metabolic imbalances which in sum have been recognized as a major predictor of cardiovascular and all-cause mortality. The aim of this study was to assess the level of under-pharmacy and poly-pbarmacy and its prognostic impact in elderly patients with metabolic syndrome. Methods Retrospective chart-review at a tertiary medical center, of 324 patients greater than 65 years of age who met the International Diabetes Foundation criteria for metabolic syndrome diagnosis [Body Mass Index (BMI) 〉 30 kg/m2, diagnosis of type 2 diabetes, hypertension, and dyslipidemia]. Results There were 60 (18.5%) patients in the low (〈 5) medication burden group, 159 (49.1%) in the medium (〉 5 and 〈 10) medication burden group, and 105 (32.4%) in the high (〉 10) medication burden group. At baseline, the groups differed only by systolic blood pressure. At two years follow-up, the medium group had significantly better improvement in high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), HbAlc, and systolic blood pressure compared to the low medication burden group and significantly better improvement in triglycerides, Haemoglobin Alc (HbAlc) and systolic blood pressure compared to the high medication group. Decrease in HDL-C was the only variable associated with strokes. High medication burden predicted hospitalization burden. The number of anti-hypertensives, history of tobacco use, low and high medication burdens and decrease in HDL-C were all associated with death. Conclusions Both poly-pharmacy and under-pharmacy are associated with a decreased therapeutic benefit among patients with metabolic syndrome in terms of important laboratory measurements as well as clinical outcomes such as myocardial infarctions, hospitalization, and death.
基金supported by the National Key Basic Research Program of China (2015CB932200)the National Natural Science Foundation of China (61704076)+2 种基金the Natural Science Foundation of Jiangsu Province (BK20171018)Jiangsu Specially-Appointed Professor Program (54935012)the support from the Fundamental Research Funds for the Central Universities (31020180QD094)
文摘Despite red phosphorous(P)-based anodes hold great promise for advanced lithium-ion batteries due to their high theoretical capacity, their practical application is hindered by poor electronic conductivity and drastic volume changes during charge-discharge processes. In order to tackle these issues, herein, a facile grinding method was developed to embed sub-micro-and nano-sized red P particles in N,P-codoped hierarchical porous carbon(NPHPC). Such a unique structure enables P@NPHPC long-cyclic stability(1120 mAh g^-1 after 100 cycles at 100 mA g^-1) and superior rate performance(248 mA h g^-1 at 6400 mA g^-1). It is believed that our method holds great potential in scalable synthesis of P@carbon composites for future practical applications.