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1.
Huan Jing Ke Xue ; 42(11): 5162-5168, 2021 Nov 08.
Article in Chinese | MEDLINE | ID: mdl-34708955

ABSTRACT

A volatile organic compounds(VOCs) emission source classification and accounting system from domestic sources in China was established for the period between 2010 and 2018. Suggestions for the prevention and treatment of VOCs from domestic sources were developed and proposed. The results showed that the total VOCs emission inventory from domestic sources in China in 2018 was 2518 kt. Architectural decoration, asphalt road paving, cooking, and rural household biomass use source were the four largest contributors, accounting for 69.22% of the total emissions. Chemical household products and urban and rural coal use contributed equally, accounting for 10.43% and 9.98%, respectively, whilst car repair accounted for 7.75%. Shandong, Sichuan, Henan, Guangdong, Jiangsu, and Hebei were the six provinces that contributed the most(36.01%). During the 2010-2018 period, China's domestic VOCs emissions increased at a rate of 0.43%, and after reaching a peak in 2013, the emissions began to decline at a rate of 2.23%. The reason for the decline was that, on the one hand, the cleaner energy consumption of residents made a contribution to the gradual reduction of domestic coal and biomass consumption. On the other hand, the gradual saturation of housing construction in some areas, which led to a decrease in the annual construction of the country. It is recommended to promote the comprehensive management of architectural decoration, cooking methods, and car repair, while paying attention to the VOCs emissions from asphalt road paving. Meanwhile, continue to optimize the energy use structure of domestic sources, and promote the pollution control of civil coal and household biomass combustion in accordance with local regulations and multiple measures.


Subject(s)
Air Pollutants , Ozone , Volatile Organic Compounds , Air Pollutants/analysis , China , Environmental Monitoring , Ozone/analysis , Volatile Organic Compounds/analysis
2.
Sci Total Environ ; 656: 239-249, 2019 Mar 15.
Article in English | MEDLINE | ID: mdl-30504024

ABSTRACT

Black carbon (BC) is important due to its complex influences on the environment and on climate in particular. However, reported BC data are largely dependent on measurement techniques due to the multitude of measurement principles. Here we focused on thermal-optical method which has been widely used to determine BC mass (as elemental carbon, EC). Several factors influencing EC measurement were investigated. Results from source samples representing vehicle engine emissions pointed to a continuum of EC components in thermal stability and provided direct observational evidence for the premature evolution of EC in inert atmosphere. It was also found that EC masses may be substantially underestimated for the vehicle exhaust samples if the adopted protocol requires an oxidizing atmosphere to define the split point between organic carbon (OC) and EC. Results from a field campaign conducted during winter in Beijing showed that the optical attenuation (ATN; i.e., the filter transmittance signal, I) was largely saturated for the samples with relatively high loadings, indicating their EC results were unreliable. Improved measurement of EC was achieved by extracting these heavily loaded filters using methanol, given that ATN was considerably reduced by the extraction and, moreover, saturation of ATN (or I) became not evident for the extracted samples. The methanol extraction also significantly reduced the transformation of OC to char-OC, by removing the majority (i.e., ~85%) of the deposited organic aerosols. Higher EC were measured for the extracted samples compared with the untreated ones, indicating that EC tends to be underestimated due to the charring-induced uncertainties. In addition, the methanol extraction largely reduced the inter-protocol discrepancy in the EC measurement results. Similar effects of methanol extraction have been observed during summer in Beijing, despite the seasonal variations of aerosol sources and compositions. This study indicates the potential benefits of methanol extraction for EC measurement.

3.
J Chromatogr Sci ; 56(8): 679-686, 2018 Sep 01.
Article in English | MEDLINE | ID: mdl-29718140

ABSTRACT

A poly(Methacrylate-co-Ethyleneglycol dimethacrylate) monolithic column was prepared in situ for high performance liquid chromatography and characterized utilizing scanning electron microscopy, thermodynamic parameters and linear solvation energy relationship methodology. The results revealed that there were many microglobules forming the larger cluster in poly(Methacrylate-co-Ethyleneglycol dimethacrylate) monolith prepared under the selected preparation conditions, which composed continuously aligned macroporous channels through the monolith skeleton. The poly(Methacrylate-co-Ethyleneglycol dimethacrylate) monolithic column had a good permeability, a high mechanical stability. The interaction model for each probe molecule on the poly(Methacrylate-co-Ethyleneglycol dimethacrylate) monolithic column was invariable within the studied temperature range due to an excellent linear relationship between lnk and 1/T for each probe molecule. The chromatographic retention for each probe molecule on the poly(Methacrylate-co-Ethyleneglycol dimethacrylate) monolithic column was an enthalpy-driven process due to |∆H°| > |T∆S°| and ∆G°<0. The main interaction forces of the poly(Methacrylate-co-Ethyleneglycol dimethacrylate) monolith with probe molecules contain hydrogen bonding interaction, hydrophobic interaction and dipole-dipole interaction. However, the contribution of each interaction was in the order of hydrogen bonding acidity > hydrophobic interactions > dipole-dipole interaction > hydrogen bonding basicity. In addition, the poly(Methacrylate-co-Ethyleneglycol dimethacrylate)monolithic column is suitable for the separation of both nonpolar and polar compounds.

4.
J Photochem Photobiol B ; 153: 380-90, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26555641

ABSTRACT

The binding interactions of three kinds of tyrosine kinase inhibitors (TKIs), such as gefitinib, lapatinib and sunitinib, with bovine serum albumin (BSA) were studied using ultraviolet spectrophotometry, fluorescence spectroscopy, circular dichroism (CD), Fourier transform infrared spectroscopy (FT-IR) and molecular docking methods. The experimental results showed that the intrinsic fluorescence quenching of BSA induced by the three TKIs resulted from the formation of stable TKIs-BSA complexes through the binding interaction of TKIs with BSA. The stoichiometry of three stable TKIs-BSA complexes was 1:1 and the binding constants (Kb) of the three TKIs-BSA complexes were in the order of 10(4)M(-1) at 310 K, indicating that there was a strong binding interaction of the three TKIs with BSA. Based on the analysis of the signs and magnitudes of the free energy change (ΔG(0)), enthalpic change (ΔH(0)) and entropic change (ΔS(0)) in the binding process, it can be deduced that the binding process of the three TKIs with BSA was spontaneous and enthalpy-driven process, and the main interaction forces between the three TKIs and BSA were van der Waals force and hydrogen bonding interaction. Moreover, from the results of CD, FT-IR and molecular docking, it can be concluded that there was a significant difference between the three TKIs in the binding site on BSA, lapatinib was located on site II (m) of BSA while gefitinib and sunitinib were bound on site I of BSA, and there were some changes in the BSA conformation when binding three TKIs to BSA but BSA still retains its secondary structure α-helicity.


Subject(s)
Indoles/metabolism , Pyrroles/metabolism , Quinazolines/metabolism , Serum Albumin, Bovine/metabolism , Animals , Binding Sites , Cattle , Circular Dichroism , Fluorescence Resonance Energy Transfer , Gefitinib , Indoles/chemistry , Lapatinib , Molecular Docking Simulation , Protein Binding , Protein Structure, Tertiary , Pyrroles/chemistry , Quinazolines/chemistry , Serum Albumin, Bovine/chemistry , Spectrophotometry, Ultraviolet , Spectroscopy, Fourier Transform Infrared , Sunitinib , Thermodynamics
5.
J Zhejiang Univ Sci B ; 10(9): 639-47, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19735096

ABSTRACT

Under some circumstances surgical resection is feasible in a low percentage for the treatment of deep tumors. Nevertheless, high-intensity focused ultrasound (HIFU) is beginning to offer a potential noninvasive alternative to conventional therapies for the treatment of deep tumors. In our previous study, a large scale spherical HIFU-phased array was developed to ablate deep tumors. In the current study, taking into account the required focal depth and maximum acoustic power output, 90 identical circular PZT-8 elements (diameter =1.4 cm and frequency=1 MHz) were mounted on a spherical shell with a radius of curvature of 18 cm and a diameter of 21 cm. With the developed array, computer simulations and ex vivo experiments were carried out. The simulation results theoretically demonstrate the ability of the array to focus and steer in the specified volume (a 2 cmx2 cmx3 cm volume) at the focal depth of 15 to 18 cm. Ex vivo experiment results also verify the capability of the developed array to ablate deep target tissue by either moving single focal point or generating multiple foci simultaneously.


Subject(s)
High-Energy Shock Waves/therapeutic use , Models, Biological , Muscle, Skeletal/pathology , Muscle, Skeletal/radiation effects , Transducers , Ultrasonic Therapy/instrumentation , Animals , Computer Simulation , Equipment Design , Equipment Failure Analysis , In Vitro Techniques , Swine , Ultrasonic Therapy/methods
6.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 24(4): 335-8, 2006 Aug.
Article in Chinese | MEDLINE | ID: mdl-16999354

ABSTRACT

OBJECTIVE: To explore the influence of chemosensitivity of Tca8113 cells by modified MTT assay after the animal model of Tca8113 were treated by the ultrasound hyperthermia. METHODS: The MTT assay of the BALB/C nu/nu mice model of Tca8113 cells treated by the ultrasound hyperthermia in vivo was performed. RESULTS: The chemosensitivity to the 9 kinds of drugs demonstrated no significant differences between the Tca8113 cells in the control group, the 39 degrees C-treated group and the groups treated from 41 degrees C to 44 degrees C. But significant differences between the 40 degrees C-treated group and the 41 degrees C or 42 degrees C-treated group existed. In the heating-time grades test, there were no significant differences in the chemosensitivity to the 9 kinds of drugs between these three pairs of group (the control group and the 15 min-treated group, the 30 min-treated and the 45 min-treated group, the 60 min-treated and the 75 min-treated group). But there were significant differences between the 30 min-treated or the 45 min-treated group and the 60 min-treated or the 75 min-treated group. CONCLUSION: Ultrasound hyperthermia performed in 42 degrees C for 30-45 min can improve the chemosensitivity of Tca8113 cells to some drugs significantly, which confirms the rationality of synchronous combination of hyperthermia and chemotherapy in the chemosensitivity point of view for the first time.


Subject(s)
Heating , Hyperthermia, Induced , Animals , Antineoplastic Agents , Mice , Mice, Inbred BALB C , Mice, Nude , Mouth Neoplasms
7.
Shanghai Kou Qiang Yi Xue ; 15(5): 507-11, 2006 Oct.
Article in Chinese | MEDLINE | ID: mdl-17348226

ABSTRACT

PURPOSE: To investigate the mechanism of apoptosis in Tca8113 cells induced by ultrasound hyperthermia by detecting changes in related index. METHODS: Tca8113 cells were treated in vitro by ultrasound hyperthermia in different heating temperatures (38 degrees C to 44 degrees C,10 minutes) and heating times (42 degrees C,10 to 60 minutes), and then the dynamic changes of early apoptosis and secondary necrosis treated by 42 degrees C for 10 minutes were assayed to detect deltapsim and Caspase-3 levels of different groups by flow cytometry (FCM). The means of each group were compared by ANOVA with SAS6.12 software package. RESULTS: After heated by ultrasound in 42 degrees C for 10 minutes, the early apoptosis of Tca8113 was detected. The apoptosis index reached its highest level at the 6th to 8th hour, then decreased rapidly and maintained in a lower level after 12 hours. The level of secondary necrosis increased with the level of early apoptosis, but kept in a higher level until the 10th hour, the level of secondary necrosis correlated with that of the early apoptosis (r = 0.7909, P = 0.0064). The fraction of cells with low mitochondria membrane potential and increased activity of Caspase-3 were detected either in the heating-temperature grads group or in the heating-time grads group, which showed significant relationship between thetwo apoptosis related index (r = 0.89189, P = 0.0029 in the heating-temperature grads group; r = 0.9679, P = 0.0003 in the heating-time grads group). CONCLUSIONS: Tca8113 cells developed apoptosis after heated by ultrasound hyperthermia along with deltapsim level decreasing and Caspase-3 activity increasing. Ultrasound hyperthermia induces apoptosis of Tca8113 cells by the mitochondrum-Caspase pathway.


Subject(s)
Apoptosis , Carcinoma, Squamous Cell , Tongue Neoplasms , Ultrasonic Therapy , Caspase 3 , Flow Cytometry , Hot Temperature , Humans , Mitochondria
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