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The Conversion of Non-Dispersed Polymers into Low-Potassium Anti-Collapse Drilling Fluids
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作者 Hao Hu Jian Guan +2 位作者 Shanfa Tang Jialuo Rong Yuanpeng Cheng 《Fluid Dynamics & Materials Processing》 EI 2024年第2期325-335,共11页
Different drillingfluid systems are designed according to mineral composition,lithology and wellbore stability of different strata.In the present study,the conversion of a non-dispersed polymer drillingfluid into a low ... Different drillingfluid systems are designed according to mineral composition,lithology and wellbore stability of different strata.In the present study,the conversion of a non-dispersed polymer drillingfluid into a low potas-sium anti-collapsing drillingfluid is investigated.Since the two drillingfluids belong to completely different types,the key to this conversion is represented by new inhibitors,dispersants and water-loss agents by which a non-dispersed drillingfluid can be turned into a dispersed drillingfluid while ensuring wellbore stability and reason-able rheology(carrying sand—inhibiting cuttings dispersion).In particular,the(QYZ-1)inhibitors and(FSJSS-2)dispersants are used.The former can inhibit the hydration expansion capacity of clay,reduce the dynamic shear force and weaken the viscosity;the latter can improve the sealing effect and reduce thefiltrate loss.The results have shown that after adding a reasonable proportion of these substances(QYZ-1:FSJSS-2)to the non-dispersed polymer drillingfluid,while the apparent viscosity,plastic viscosity,structural viscosity andfluidity index under-went almost negligible changes,the dynamic plastic ratio increased,and thefiltration loss decreased significantly,thereby indicating good compatibility.According to the tests(conducted in the Leijia area),the density was 1.293 g/cm3,and after standing for 24 h,the SF(static settlement factor)was 0.51.Moreover,thefiltration loss was reduced to 4.0 mL,the rolling recovery rate reached 96.92%,with excellent plugging and anti-collapse performances. 展开更多
关键词 non-dispersed polymer drilling fluid low potassium anti-collapsing drilling fluid drilling fluid conversion drilling fluid reuse filter vector
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Preparation of High Performance Non-dispersible Concrete 被引量:1
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作者 姜丛盛 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2004年第2期67-69,共3页
A new-type underwater non-dispersible concrete admixture NDA was prepared,its function mechanism was analyzed,and C40 high performance non-dispersible underwater concrete was manufactured by applying NDA.The results i... A new-type underwater non-dispersible concrete admixture NDA was prepared,its function mechanism was analyzed,and C40 high performance non-dispersible underwater concrete was manufactured by applying NDA.The results indicate that NDA has a suitable workability,low strength loss,and excellent anti-dispersion;the fresh non-dispersible underwater concrete with NDA has high anti-dispersion,excellent workability such as self-compacting and not bleeding;hardened non-dispersible underwater concrete with NDA has a high strength,high durability such as high anti-abrasion,impermeability and anticorrosion. 展开更多
关键词 non-dispersible underwater concrete high performance ANTI-WASHOUT
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Material Properties and Mold Folded Core Based on Ultra-violet Cured Resins 被引量:1
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作者 Wang Zhijin Valentin Khaliulin +1 位作者 Vitality Kovalev Oskar Khamidullin 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第5期529-535,共7页
Ultra-violet(UV)curing is an efficient method for composite molding.Firstly,thermophysical properties of UV cured glass-fiber reinforced plastics are conducted.Material properties are studied for various kinds of post... Ultra-violet(UV)curing is an efficient method for composite molding.Firstly,thermophysical properties of UV cured glass-fiber reinforced plastics are conducted.Material properties are studied for various kinds of postcuring modes.Then the UV curing method is suggested in manufacturing V-crimp folded core for sandwich panels.Two kinds of processing schemes for V-crimp folded core manufacturing using UV curing are presented.Finally,the effect of post-curing on the mechanical properties of folded core sandwiches is experimentally studied,and optimum modes of post-curing are determined.The experimental results show that the ultimate compressive strength of the folded sandwiches is increased by 60% after post-curing with the optimum post-curing mode. 展开更多
关键词 glass-fiber reinforced plastic composites ultra-violet(UV)curing V-crimp strength of folded core
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A spectroscopic study on the effect of ultra-violet solar radiation in Antarctica on the human skin fbroblast cells
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作者 Tatsuyuki Yamamoto Hideo Akiyoshi +5 位作者 Keisuke Yoshikiyo Tetsuya Takahashi Yukiko Tanabe Sakae Kudoh Satoshi Imurad Naoyuki Yamamoto 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第6期647-653,共7页
A study on the effect of the solar ultra-violet radiation on the human skin fibroblast cells revealed that the production of matrix metalloproteinase-2 was inhibited by the radiation.A CO2 incubator connected by optic... A study on the effect of the solar ultra-violet radiation on the human skin fibroblast cells revealed that the production of matrix metalloproteinase-2 was inhibited by the radiation.A CO2 incubator connected by optical fibers to a reflector telescope for collecting the solar light was built at Syowa station by the 49th Japanese Antarctica Research Expedition.The direction of the telescope was continuously controlled by a sun-tracker to follow the movement of the Sun automatically.The intensity of the collected light was monitored by a portable spectrophotometer housed inside.The human skin fibroblast cells were incubated in the CO2 chamber to investigate the effect of the solar radiation at Syowa station and were compared with those reference experiments at a laboratory in Japan.The results showed cell damage by strong UV radiation.The production of matrix metalloproteinase-2 was prompted by the moderate UV-B,but was inhibited by the strong UV-B radiation,as studied under laboratory conditions in Japan.The effect of strong solar radiation at Syowa station involving the radiation of UV-B region was estimated to be of the same extent of the radiation caused by an artificial UV-B light with the intensity more than 50 mJ/cm2. 展开更多
关键词 ANTARCTICA GEOBIOLOGY ultra-violet radiation Human skin fibroblast cells Matrix metalloproteinase
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Synthesis and Flocculation of Polyacrylamide with Low Water Absorption for Non-dispersible Underwater Concrete
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作者 LI Hongling YAN Na +2 位作者 SUN Guowen ZHENG Haorui YANG Xinyu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第6期1404-1413,共10页
The polyacrylamide which is directly added into concrete shows strong water absorption property.Thus the construction of underwater constructure would demand high amount of water,resulting in poor workability of concr... The polyacrylamide which is directly added into concrete shows strong water absorption property.Thus the construction of underwater constructure would demand high amount of water,resulting in poor workability of concrete and strength shrinkage after hardening.Herein,a kind of anionic polyacrylamide(APAM)grafted with water reducing functional group(-COOH)was synthesized at low temperatures by partial factor design and response surface design.The structure and morphology of APAM were characterized by UV,FTIR and SEM methods.The experimental results show that the molecular weight of the synthesized APAM could reach 11 million,under the condition that the temperature was 35℃,the pH value was 8,the monomer concentration was 27wt%,the initiator dosage was 0.6wt%,and the monomer ratio(n(AM):n(AA))was 3.When the APAM was applied into the underwater slurry,it presented good flocculation and low water demand.When the dosage was 1%of the mass of the cement,the water demand increased by 12%,which could meet the self-leveling and anti-dispersity of the underwater slurry at the same time.This technology provides technical guidance for the large-scale industrial production of polyacrylamide for underwater concrete construction while achieving environmental protection during production. 展开更多
关键词 non-dispersible underwater concrete anionic polyacrylamide partial factor design response surfacedesign FLOCCULATION
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Effect of GGBS on performance deterioration of non-dispersible underwater concrete in saline soil
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作者 Fang Liu BaoMin Wang +2 位作者 GuoRong Tao Tao Luo XiaoSa Yuan 《Research in Cold and Arid Regions》 CSCD 2022年第2期120-137,共18页
In saline soil areas,there are a large number of ions in soil or water environments,such as Cl^(-)and SO_(4)^(2-),which have strong corrosive interactions with buildings.To study the deterioration of non-dispersible u... In saline soil areas,there are a large number of ions in soil or water environments,such as Cl^(-)and SO_(4)^(2-),which have strong corrosive interactions with buildings.To study the deterioration of non-dispersible underwater concrete in sulfate,chloride,and mixed salt environments,the compressive strength and deterioration resistance coefficient of the studied concrete mixed with different amounts of ground granulated blast-furnace slag(GGBS)were analyzed in this paper.At the same time,the micro morphology and corrosion products distribution of the studied concrete were observed by means of SEM,plus XRD diffraction,TG-DTG and FT-IR analyses to explore the influence of corrosive solutions on the hydration products of concrete.We also analyzed the mechanism of improving the deterioration resistance of the studied concrete by adding GGBS in a saline soil environment.The results show that the compressive strength of the studied concrete in a chloride environment was close to that in a fresh water environment,which means that chloride has no adverse effect on compressive strength.The deterioration of the studied concrete was most serious in a sulfate environment,followed by mixed salt environment,and the lowest in a chloride environment.In addition,by adding GGBS,the compressive strength and deterioration resistance of the studied concrete could be effectively improved. 展开更多
关键词 saline soil non-dispersible underwater concrete granulated blast furnace slag deterioration resistance mechanism analysis
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Analysis on Pore Structure of Non-Dispersible Underwater Concrete in Saline Soil Area
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作者 Fang Liu Baomin Wang +1 位作者 Mengsai Wang Xiaosa Yuan 《Journal of Renewable Materials》 SCIE EI 2021年第4期723-742,共20页
In this paper,mercury intrusion porosimetry(MIP)is used to test the pore structure of non-dispersible underwater concrete so as to study the influence of pouring and curing environment,age and slag powder on the pore ... In this paper,mercury intrusion porosimetry(MIP)is used to test the pore structure of non-dispersible underwater concrete so as to study the influence of pouring and curing environment,age and slag powder on the pore characteristics of concrete,analyze the pore characteristics,porosity and pore distribution of concrete in different hydration stages,and reveal the relationship between pore structure and permeability of concrete.The results show that the pore-size distribution of concrete in fresh water condition is better than that in sulfate environment and mixed salt environment,and therefore,sulfate as well as mixed salt are not conducive to the development of pore structure of non-dispersible underwater concrete;chlorine salt has little effect on the pore structure of nondispersible underwater concrete;under the three conditions of sulfate,chlorine and mixed salt,the porosity of concrete mixed with slag powder is lower than that of concrete without slag powder.The results indicate that the addition of slag powder can ameliorate the pore size distribution of non-dispersed underwater concrete,reduce the porosity,and make the concrete structure more compact,which is beneficial to improve the permeability resistance of concrete at the macro level. 展开更多
关键词 non-dispersible underwater concrete slag powder saline soil mercury intrusion porosimetry(mip) pore structure
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Photocatalytic Activity of Titanium Dioxide Powder Fabricated from an Anodized Titanium Sheet under Ultra-Violet and Visible Light Irradiation
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作者 Michio Kaneko Kiyonori Tokuno +2 位作者 Kazuo Yamagishi Takao Wada Tsuyoshi Hasegawa 《Journal of Surface Engineered Materials and Advanced Technology》 2017年第1期13-23,共11页
A commercially pure titanium sheet with titanium carbide (TiC) precipitated in its surface layer was anodized in NH4NO3 aqueous solution and heat treated in air. The photocatalytic activity of titanium dioxide powder ... A commercially pure titanium sheet with titanium carbide (TiC) precipitated in its surface layer was anodized in NH4NO3 aqueous solution and heat treated in air. The photocatalytic activity of titanium dioxide powder collected from the surface of the anodized titanium sheet was evaluated under ultra-violet and visible light irradiation. It showed relatively high photocatalytic activity in 0.1 mol/l potassium iodide solution, which was almost equal to the activity level of TiO2 powder (P-25) manufactured by Degussa Corporation. The better photocatalytic activity under ultra-violet irradiation is considered to be related to the formation of anatase type titanium dioxide. Photocatalytic activity under visible light irradiation was also observed, which was considered to be attributable to impurity doping, (carbon), in the titanium dioxide powder. 展开更多
关键词 Photocatalysis TITANIUM TITANIUM Dioxide POWDER Anodic Oxidation ultra-violet VISIBLE-LIGHT Response
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Detecting Ultra-Violet Radiation by Using Titanium Dioxide Nanoparticles
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作者 Naser Hatefi Kargan Mousa Aliahmad Samereh Azizi 《Soft Nanoscience Letters》 2012年第3期29-33,共5页
In this paper sensitivity of chemically synthesized titanium dioxide (TiO2) nanoparticles to ultra-violet (UV) radiation is investigated. For this purpose three types of ultra-violet photodetectors were fabricated, on... In this paper sensitivity of chemically synthesized titanium dioxide (TiO2) nanoparticles to ultra-violet (UV) radiation is investigated. For this purpose three types of ultra-violet photodetectors were fabricated, one with as-synthesized TiO2 nanoparticles, another one with TiO2 nanoparticles annealed at 600℃, and the third one with TiO2 nanoparticles annealed at 800℃. In each case the annealing time duration was one hour. The photodetectors were fabricated on glass slides where on them a thin layer of fluorine doped tin oxide (FTO) was deposited by spray pyrolysis. The results show that all photodetectors are sensitive to UV radiation where the photodetectors fabricated from annealed TiO2 nanoparticles are more sensitive than the photodetectors fabricated from as-synthesized TiO2 nanoparticles. 展开更多
关键词 ultra-violet PHOTODETECTOR TITANIUM Dioxide NANOCRYSTALS Nanoparticles
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Biological Defenses against Ultra-Violet, Visible Light, and Near-Infrared Exposure
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作者 Yohei Tanaka Hideki Motomura Masafumi Jinno 《Optics and Photonics Journal》 2016年第1期8-14,共7页
Objective: Humans are increasingly exposed to artificial light and electromagnetic wave radiation, in addition to solar radiation. Many studies have shown the biological effects of ultra-violet and near-infrared expos... Objective: Humans are increasingly exposed to artificial light and electromagnetic wave radiation, in addition to solar radiation. Many studies have shown the biological effects of ultra-violet and near-infrared exposure, but few have extensively investigated the innate biological defenses within human tissues against visible light and near-infrared exposure. Herein, we investigated spectral properties of endogenous human biological defenses against ultra-violet to near-infrared. Methods: A double-beam spectrophotometer (190 - 2700 nm) was used to measure the transmission spectra of a saline solution used to imitate perspiration, and oil to imitate sebum, as well as human skin, blood, adipose tissue, and muscle. Results: Saline (thickness, 0.5 mm) blocked 27.5% - 98.6% of ultra-violet, 13.2% - 34.3% of visible light, and 10.7% - 99.8% of near-infrared. Oil (thickness, 0.5 mm) blocked 50.5% - 100% of ultra-violet, 28.7% - 54.8% of visible light, and 19.0% - 98.3% of near-infrared. Blood thicknesses of 0.05 and 0.5 mm blocked over 97.8%, 100% of ultra-violet, over 94.6%, 99.7% of visible light, and over 75.8%, 99.4% of near-infrared, respectively. Skin thicknesses of 0.25 and 0.5 mm blocked over 99.4%, 100% of ultra-violet and over 94.3%, 99.7% of visible light, and over 74.7%, 93.5% of near-infrared, respectively. Adipose tissue thickness of 0.25 and0.5 mm blocked over 98.3%, 100% of ultra-violet, over 94.7%, 99.7% of visible light, and over 88.1%, 98.6% of near-infrared, respectively. Muscle thickness of 0.25 and0.5 mm blocked over 95.4%, 99.8% of ultra-violet, over 93.1%, 99.5% of visible light, and over 86.9%, 98.3% of near-infrared, respectively. Conclusions: Humans possess endogenous biological protection against ultra-violet, visible light and near-infrared exposure on multiple levels, including through perspiration, sebum, blood, skin, adipose tissue, and muscle. Since solar and artificial radiation affects human tissues, biological defenses made of biological materials may be induced to protect subcutaneous tissues against these wavelengths. 展开更多
关键词 Biological Defenses NEAR-INFRARED ultra-violet Visible Light
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Recent Progress of the Solar Wind Magnetosphere Ionosphere Link Explorer (SMILE) Mission
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作者 WANG Chi ESCOUBET Philippe +2 位作者 FORSYTH Colin LI Jing AGNOLON David 《空间科学学报》 CAS CSCD 北大核心 2024年第4期692-698,共7页
The SMILE(Solar wind Magnetosphere Ionosphere Link Explorer)mission is a joint space science mission between the Chinese Academy of Sciences(CAS)and the European Space Agency(ESA),aiming to understand the interaction ... The SMILE(Solar wind Magnetosphere Ionosphere Link Explorer)mission is a joint space science mission between the Chinese Academy of Sciences(CAS)and the European Space Agency(ESA),aiming to understand the interaction of the solar wind with the Earth’s magnetosphere in a global manner.As of May 2024,the SMILE mission is in phase-D with an expected launch date of September 2025.This report summarizes developments in the mission during the past two years. 展开更多
关键词 SMILE Soft X-ray Imager ultra-violet Imager Light Ion Analyzer MAGNETOMETER
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Photoionization Mass Spectrometric and Kinetic Modeling of Low-pressure Pyrolysis of Benzene 被引量:2
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作者 杨玖重 赵龙 +2 位作者 蔡江淮 齐飞 李玉阳 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第3期245-251,I0003,共8页
Pyrolysis of benzene at 30 Torr was studied from 1360 K to 1820 K in this work. Synchrotron vacuum ultraviolet photoionization mass spectrometry was employed to detect the pyroly- sis products such as radicals, isomer... Pyrolysis of benzene at 30 Torr was studied from 1360 K to 1820 K in this work. Synchrotron vacuum ultraviolet photoionization mass spectrometry was employed to detect the pyroly- sis products such as radicals, isomers and polycyclic aromatic hydrocarbons, and measure their mole fraction profiles versus temperature. A low-pressure pyrolysis model of benzene was developed and validated by the experimental results. Rate of production analysis was performed to reveal the major reaction networks in both fuel decomposition and aromatic growth processes. It is concluded that benzene is mainly decomposed via H-abstraction reaction to produce phenyl and partly decomposed via unimolecular decomposition reac- tions to produce propargyl or phenyl. The decomposition process stops at the formation of acetylene and polyyne species like diacetylene and 1,3,5-hexatriyne due to their high thermal stabilities. Besides, the aromatic growth process in the low-pressure pyrolysis of benzene is concluded to initiate from benzene and phenyl, and is controlled by the even carbon growth mechanism due to the inhibited formation of C5 and C7 species which play important roles in the odd carbon growth mechanism. 展开更多
关键词 BENZENE Low-pressure pyrolysis PAH formation Synchrotron vacuum ultra-violet photoionization mass spectrometry Kinetic model
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IMPROVEMENT OF DIMENSIONAL ACCURACY FOR GOLD MICROPART PREPARED BY UV-LIGA
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作者 曲宁松 苏兴 +1 位作者 李寒松 曾永彬 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第4期325-330,共6页
The swelling of SU-8 mold is one of the most important factors influencing the dimensional accuracy of a metal mieropart produced by ultra-violet lithography galvanik abformung(UV-LIGA). The isolation belt struc- tu... The swelling of SU-8 mold is one of the most important factors influencing the dimensional accuracy of a metal mieropart produced by ultra-violet lithography galvanik abformung(UV-LIGA). The isolation belt struc- ture is usually employed to enhance the dimensional accuracy of electroformed metal mieropart. However, noble metal is wasted because the isolation belt is filled with metal when noble metal mieroparts are fabricated. There- fore, a semi-isolation belt structure is presented to save noble metal. Furthermore, a high current density is also introduced to shorten the eleetroforming time, and thus the dimensional accuracy of electroformed gold micropart is improved by using the electrolyte jet. The experimental results indicate that both the semi-isolation belt and the high current density can help to enhance the dimensional accuracy of electroformed gold micropart. Its dimen- sional error is only 5 μm at the current density of 0. 6 A/dm2 while the semi-isolation belt structure is used. 展开更多
关键词 ultra-violet lithography galvanik abformung (UV-LIGA) microelectroforming micropart dimen- sional accuracy swelling of SU-8 structure
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应用增爬群改善大雨条件下800 kV叠锥型支柱绝缘子的雨闪性能(英文) 被引量:5
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作者 Orsino Oliveira Filho José Antonio Cardoso +2 位作者 Darcy Ramalho de Mello Rogério Magalhes de Azevedo Sylvia G Carvalho 《高电压技术》 EI CAS CSCD 北大核心 2011年第11期2772-2779,共8页
Studies based on AC high voltage tests have been done at Cepel to investigate the performance of 800 kV busbar insulators under heavy wetting conditions.Insulators were tested which are now used on site and also with ... Studies based on AC high voltage tests have been done at Cepel to investigate the performance of 800 kV busbar insulators under heavy wetting conditions.Insulators were tested which are now used on site and also with different configurations of booster sheds.Images recorded by ultra-violet(UV) camera were used to help the investigations on the effectiveness of booster sheds.By comparing UV images of the insulator being stressed with high voltage under heavy artificial rain,with and without booster sheds,it was possible to observe how significant the reduction on the flashover formation process was when booster sheds were used.The effectiveness of booster sheds was also quantified by determining the disruptive discharge of the insulator with and without them.The results of these studies can also be considered as contribution to national and international standard technical committees to improving the standardized procedure for tests on ultra high voltage(UHV) insulators under heavy rain.Subjects such as the clear definition of relevant UHV test procedure and test arrangements,including the use of UV camera,have to be taken into account. 展开更多
关键词 UHV insulator heavy rain booster sheds wet tests disruptive discharge ultra-violet images
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Portable Analyzer for Rapid Analysis of Total Protein, Fat and Lactose Contents in Raw Milk Measured by Non-dispersive Short-wave Near-infrared Spectrometry 被引量:6
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作者 FENG Xu-dong SU Rui XU Nan WANG Xing-hua YU Ai-min ZHANG Han-qi CAO Yan-bo 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2013年第1期15-19,共5页
A novel portable analyzer for raw milk quality control during the material purchase at dairy plants was developed, by which the percentages(mass fraction) of main components including total protein, fat, and lactose... A novel portable analyzer for raw milk quality control during the material purchase at dairy plants was developed, by which the percentages(mass fraction) of main components including total protein, fat, and lactose of an unhomogenized milk sample could be determinated in 1 min with the help of non-dispersive short-wave near-infrared (NDSWNIR) spectrometry in a wavelength range from 600 nm to 1100 nm and multivariate calibration. The analyzer was designed with a single-beam optical system, which comprised a temperature control module, a multi-channel narrow-band light source(16 wavelengths), a glass absorption cell with 15 mm sample thickness, a silicon photodiode detector, several compound lenses and a recorder module. A total of 80 raw milk samples were collected at a dairy farm twice a month for 4 months. The samples were scanned with a common UV-Vis-NIR spectrometer and analyzed according to China GB standard methods. The uninformative variables elimination(UVE) method was carried out on the spectrum data and the percentages of main components of all the samples to choose the peak emitting wavelength of each channel of the light source. Another 90 raw milk samples were collected from the same dairy farm thrice a month for 3 months. The samples were analyzed according to China GB standard methods and with the proposed analyzer. The percentages of the main components and the NDSWNIR absorption data of the samples were used for the construction and validation of the multivariate calibration model with partial least squares(PLS) method. The root-mean-square errors of prediction(RMSEP) of total protein, fat and lactose were 0.201, 0.172 and 0.247 and the coefficients of correlation(R) were 0.932, 0.981 and 0.933, respectively. 展开更多
关键词 Portable analyzer Raw milk non-dispersive short-wave near-infrared(NDSWNIR) spectrometry Multiva-riate calibration
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Cross-interference correction and simultaneous multi-gas analysis based on infrared absorption 被引量:3
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作者 孙友文 曾议 +5 位作者 刘文清 谢品华 陈嘉乐 李先欣 汪世美 黄书华 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期168-175,共8页
In this paper, we present simultaneous multiple pollutant gases (CO2, CO, and NO) measurements by using the non-dispersive infrared (NDIR) technique. A cross-correlation correction method is proposed and used to c... In this paper, we present simultaneous multiple pollutant gases (CO2, CO, and NO) measurements by using the non-dispersive infrared (NDIR) technique. A cross-correlation correction method is proposed and used to correct the cross-interferences among the target gases. The calculation of calibration curves is based on least-square fittings with third-order polynomials, and the interference functions are approximated by linear curves. The pure absorbance of each gas is obtained by solving three simultaneous equations using the fitted interference functions. Through the interference correction, the signal created at each filter channel only depends on the absorption of the intended gas. Gas mixture samples with different concentrations of CO2, CO, and NO are pumped into the sample cell for analysis. The results show that the measurement error of each gas is less than 4.5%. 展开更多
关键词 environmental pollution measurements optical measurement technology non-dispersive infrared technique gas analysis
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Observation and modeling of vertical carbon dioxide distribution in a heavily polluted suburban environment 被引量:3
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作者 BAO Zhongxiu HAN Pengfei +6 位作者 ZENG Ning LIU Di CAI Qixiang WANG Yinghong TANG Guiqian ZHENG Ke YAO Bo 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第4期371-379,共9页
The vertical distribution of carbon dioxide(CO2)is important for the calibration and validation of transport models and remote sensing measurements.Due to the large mass and volume of traditional instruments as well a... The vertical distribution of carbon dioxide(CO2)is important for the calibration and validation of transport models and remote sensing measurements.Due to the large mass and volume of traditional instruments as well as supporting systems,in-situ measurements of the CO2 vertical profile within the boundary layer are rare.This study used a miniaturized CO2 monitoring instrument based on a low-cost non-dispersive infrared(NDIR)sensor to measure the CO2 vertical profile and meteorological parameters of the lower troposphere(0–1000 m)in southwestern Shijiazhuang,Hebei Province,China.The sensors were onboard a tethered balloon with two processes:the ascending process and the descending process.The results showed that the overall trend of CO2 concentration decreased with height.Weather conditions and CO2 emission sources caused fluctuations in CO2 concentrations.The CO2 concentration varied from morning to afternoon due mainly to the faster spread of air mass during daytime,with strong convections and the accumulation of emissions at night.The low-cost sensor produced results consistent with the traditional gas chromatography method.The Weather Research and Forecasting model could not capture the CO2 profiles well due mainly to the bad performances in boundary layer height and the potential outdated fossil fuel emissions around the experimental site.This experiment is the first successful attempt to observe the CO2 vertical distribution in the lower troposphere by using lowcost NDIR sensors.The results help us to understand the vertical structure of CO2 in the boundary layer,and provide data for calibrating and validating transport models. 展开更多
关键词 Low cost sensor co2 vertical profile tethered balloon meteorological conditions non-dispersive infrared(NDIR)
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Depletion of the Ozone Layer and Its Consequences: A Review 被引量:2
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作者 Anjali Aggarwal Reeta Kumari +8 位作者 Neeti Mehla   Deepali Rishi Pal Singh Sonal Bhatnagar Kameshwar Sharma Kuldeep Sharma Vashishtha Amit Brijesh Rathi 《American Journal of Plant Sciences》 2013年第10期1990-1997,共8页
Ozone (O3) is a stratospheric layer that plays important role in providing support to humans for their survival. It is an essential factor for many global, biological and environmental phenomena. The ultra-violet (UV)... Ozone (O3) is a stratospheric layer that plays important role in providing support to humans for their survival. It is an essential factor for many global, biological and environmental phenomena. The ultra-violet (UV) rays emitted from sun are captured by ozone and thereby provide a stable ontological structure in the biosphere. Various anthropogenic activities such as emissions of CFCs, HCFCs and other organo-halogens lead to the depletion of ozone. The ozone depletion resulted in secondary production of an ozone layer near the ground (terrestrial ozone layer), which is responsible for adverse effects on plants, humans and environment with increased number of bronchial diseases in humans. The mutations caused by UV rays result in variation in morphogenic traits of plants which ultimately decreases crop productivity. However, UV radiation is required in optimum intensity for both plants and animals. This review takes into an account the wide ranging effects of ozone depletion with a majority of them being detrimental to the plant system. 展开更多
关键词 OZONE Depletion ultra-violet RADIATION CHLOROFLUOROCARBONS PLANTS ECOSYSTEM
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Experimental study and kinetic analysis of oxidant-free thermal-assisted UV digestion utilizing supported nano-TiO_2 photocatalyst for detection of total phosphorous 被引量:1
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作者 董甜 佟建华 +2 位作者 边超 孙楫舟 夏善红 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期93-99,共7页
A novel thermal-assisted ultra-violet(UV) photocatalysis digestion method for the determination of total phosphorus(TP) in water samples was introduced in this work. The photocatalytic experiments for TP digestion wer... A novel thermal-assisted ultra-violet(UV) photocatalysis digestion method for the determination of total phosphorus(TP) in water samples was introduced in this work. The photocatalytic experiments for TP digestion were conducted using a 365 nm wavelength UV light and Ti O2 particles as the photocatalyst. Sodium tripolyphosphate and sodium glycerophosphate were used as the typical components of TP and the digested samples were then determined by spectrophotometry after phosphomolybdenum blue reaction. The effects of operational parameters such as reaction time and temperature were studied for the digestion of TP and the kinetic analysis of two typical components was performed in this paper. The pseudo-first-order rate constants k of two phosphorus compounds at different temperatures were obtained and the Arrhenius equation was employed to explain the effect of temperature on rate constant k. Compared with the conventional thermal digestion method for TP detection, it was found that the temperature was decreased from 120 °C to 60 °C with same conversion rate and time in this thermal-assisted UV digestion method, which enabled the digestion process work at normal pressure. Compared with the individual ultra-violet(UV) photocatalysis process, the digestion time was also decreased from several hours to half an hour using the thermal-assisted UV digestion method. This method will not lead to secondary pollution since no oxidant was needed in the thermal-assisted UV photocatalysis digestion process, which made it more compatible with electrochemical detection of TP. 展开更多
关键词 Thermal-assisted ultra-violet digestion Ti O2 Oxidant-free Kinetic analysis
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A low-cost in-situ CO_(2) sensor based on a membrane and NDIR for long-term measurement in seawater 被引量:2
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作者 Meng LI Baolu DU +3 位作者 Jinjia GUO Zhihao ZHANG Zeyu LU Rong’er ZHENG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第3期986-998,共13页
The multi-point simultaneous long-term measurement of CO_(2) concentration in seawater can provide more-valuable data for further understanding of the spatial and temporal distribution of CO_(2).Thus,the requirement f... The multi-point simultaneous long-term measurement of CO_(2) concentration in seawater can provide more-valuable data for further understanding of the spatial and temporal distribution of CO_(2).Thus,the requirement for a low-cost sensor with high precision,low power consumption,and a small size is becoming urgent.In this work,an in-situ sensor for CO_(2) detection in seawater,based on a permeable membrane and non-dispersive infrared(NDIR)technology,is developed.The sensor has a small size(Ф66 mm×124 mm),light weight(0.7 kg in air),low power consumption(<0.9 W),low cost(<US$1000),and high-pressure tolerance(<200 m).After laboratory performance tests,the sensor was found to have a measurement range of(0–2000)×10^(-6),and the gas linear correlation R^(2) is 0.99,with a precision of about 0.98%at a sampling rate of 1 s.A comparison measurement was carried out with a commercial sensor in a pool for 7 days,and the results showed a consistent trend.Further,the newly developed sensor was deployed in Qingdao nearshore water for 35 days.The results proved that the sensor could measure the dynamic changes of CO_(2) concentration in seawater continuously,and had the potential to carry out long-term observations on an oceanic platform.It is hoped that the sensor could be applied to field ocean observations in near future. 展开更多
关键词 in-situ sensor dissolved CO_(2) long-term measurement permeable membrane non-dispersive infrared(NDIR) LOW-COST
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