1,424 research outputs found
Quantity and quality of China's water from demand perspectives
China is confronted with an unprecedented water crisis regarding its quantity and quality. In this study, we quantified the dynamics of China's embodied water use and chemical oxygen demand (COD) discharge from 2010 to 2015. The analysis was conducted with the latest available water use data across sectors in primary, secondary and tertiary industries and input-output models. The results showed that (1) China's water crisis was alleviated under urbanisation. Urban consumption occupied the largest percentages (over 30%) of embodied water use and COD discharge, but embodied water intensities in urban consumption were far lower than those in rural consumption. (2) The 'new normal' phase witnessed the optimisation of China's water use structures. Embodied water use in light-manufacturing and tertiary sectors increased while those in heavy-manufacturing sectors (except chemicals and transport equipment) dropped. (3) Transformation of China's international market brought positive effects on its domestic water use. China's water use (116-80 billion tonnes (Bts))9 and COD discharge (3.95-2.22 million tonnes (Mts)) embodied in export tremendously decreased while its total export values (11-25 trillion CNY) soared. Furthermore, embodied water use and COD discharge in relatively low-end sectors, such as textile, started to transfer from international to domestic markets when a part of China's production activities had been relocated to other developing countries
Tetraaqua{1-[(1H-1,2,3-benzotriazol-1-yl)methyl]-1H-1,2,4-triazole}sulfatocadmium dihydrate
In the title complex, [Cd(SO4)(C9H8N6)(H2O)4]·2H2O, the CdII ion is six-coordinated by one N atom from a 1-[(1H-1,2,3-benzotriazol-1-yl)methyl]-1H-1,2,4-triazole ligand and by five O atoms from four water molecules and one monodentate sulfate anion in a distorted octahedral geometry. The sulfate tetrahedron is rotationally disordered over two positions in a 0.651 (12):0.349 (12) ratio. In the crystal, adjacent molecules are linked through O—H⋯O and O—H⋯N hydrogen bonds into a three-dimensional network
Thymol exerts anti-inflammatory effect in dextran sulfate sodium-induced experimental murine colitis
Purpose: To investigate the effect of thymol on dextran sulfate sodium (DSS)-induced experimental colitis in mice.Methods: Colitis in mice was induced by drinking water with 2.5 % (w/v) DSS. The levels of myeloperoxidase (MPO), malondialdehyde (MDA), glutathione (GSH) and superoxide (SOD) in colonic tissues were determined using commercial kits. Histological changes were evaluated by hematoxylin and eosin staining. The production of nitric oxide (NO) was measured by Griess assay. The levels of pro-inflammatory cytokines including TNF-α, IL-1β and IL-6 were assessed by quantitative PCR and ELISA kits. Nuclear factor-kappaB (NF-κB) pathway activation was determined by Western blot.Results: Thymol markedly reduced disease activity index (DAI) scores, and recovered the colon length. Histological damage and MPO levels in the colonic tissues were markedly inhibited (p < 0.05) by thymol, which also reduced mRNA expressions of TNF-α, IL-1β and IL-6 in the colon. In addition, it downregulated MDA level but elevated GSH and SOD levels. Moreover, in vitro data showed that thymol significantly inhibited (p < 0.05) lipopolysaccharide-induced secretion of NO, TNF-α, IL-1β and IL-6 in macrophages, and suppressed (p < 0.05) the activation of NF-κB pathway.Conclusion: Thymol attenuates experimental colitis by down-regulating the activation of NF-κB pathway. Therefore, thymol is a potential candidate drug for the management of ulcerative colitis.Keywords: Thymol, Ulcerative colitis, Dextran sulfate sodium, Macrophages, Nuclear factor-kappa
Simultaneous determination of ten compounds in two main medicinal plant parts of Tibetan herb, Pterocephalus hookeri (CB Clarke) Höeck, by ultra-high performance liquid chromatography-photodiode array
Purpose: To develop an ultra-high performance liquid chromatography (UPLC) - photodiode array (PDA) method to compare the chemical composition of two different medicinal components of Pterocephalus hookeri.Methods: Samples were chromatographically separated in succession using Waters Acquity UPLCR BEH C18 column (2.1 × 100 mm, 1.7 μm) and gradient elution (0.2 % phosphoric acid aqueous -acetonitrile). Using partial least squares discriminant analysis and one-way analysis of variance, attempts were made to distinguish different medicinal parts of P. hookeri.Results: Regression equation for 10 compounds showed good linear regression (R2 > 0.9994). The relative standard deviations of precision, stability, repeatability and recovery were under 5 %. Compared with the aerial plant part, the root had significantly higher levels of sylvestroside I (p < 0.01), cantleyoside (p < 0.001), dipsanosides B (p < 0.01) and dipsanosides A (p < 0.01), but significantly lower levels of loganic acid (p < 0.001), chlorogenic acid (p < 0.01), and isochlorogenic acid (p < 0.01). There were no significant differences between loganin, sweroside and isochlorogenic acid C.Conclusion: The described method is simple, accurate and reproducible, and can be used for the simultaneous determination of 10 major compounds of P. hookeri. The results demonstrate that there is variation in the chemical composition of the aerialpart and root of P. hookeri and that loganic acid and cantleyoside are the primary chemical biomarkers.Keywords: Tibetan medicine, Pterocephalus hookeri, Medicinal parts, Loganic acid and Cantleyoside, UPLC-PD
Reliability Analysis of a Repairable C (2, 3; G ) System with Repair Priority and one is"as good as new"
In this paper, we discuss a repairable linear C (2, 3; G) system. One repairman carries out the maintenance of the system. It is assumed that the working time and the repair time of each component in the system are both exponentially distributed and only one component after repair is as good as new. Each component is classified as either a key component or an ordinary one according to its priority role to the system’s repair. We apply the geometric process, supplementary variable technique and generalized Markov process to study a repairable linear C (2, 3; G) system. We obtain Laplace transforms of some reliability indices such as availability and reliability.Key words: repairable system; generalized Markov process; key component; geometric proces
MODAL RESPONSE AND VIBRATION CHARACTERISTICS OF SUGAR BEET COMBINE HARVESTER FRAME
ABSTRACT In complex environments, beet harvesters vibrate strongly under the influence of multiple sources of excitation. The modal constraints of the harvester's frame were obtained using modal simulation, and the accuracy of the finite element model was verified through SIMO modal testing. Additionally, field experiments were conducted to collect the vibration signals of the harvester under various conditions. Time-domain analysis revealed that the RMS value of the frame's Z-axis acceleration was highest in sugar beet fields and lowest on unpaved roads. There is a correlation between the operation of working components and changes in amplitude. Frequency domain analysis determined that the main vibration frequency of the frame was in the range of 0–75 Hz, and the operating frequency of the engine (35 Hz) and the power input shaft (12.7 Hz) excites the constrained modal of the frame, which may lead to resonance. Integrating the results of the modal response and vibration testing provides a more comprehensive approach to studying the vibration characteristics of agricultural machinery
Data Processing Pipeline for Pointing Observations of Lunar-based Ultraviolet Telescope
We describe the data processing pipeline developed to reduce the pointing
observation data of Lunar-based Ultraviolet Telescope (LUT), which belongs to
the Chang'e-3 mission of the Chinese Lunar Exploration Program. The pointing
observation program of LUT is dedicated to monitor variable objects in a
near-ultraviolet (245-345 nm) band. LUT works in lunar daytime for sufficient
power supply, so some special data processing strategies have been developed
for the pipeline. The procedures of the pipeline include stray light removing,
astrometry, flat fielding employing superflat technique, source extraction and
cosmic rays rejection, aperture and PSF photometry, aperture correction, and
catalogues archiving, etc. It has been intensively tested and works smoothly
with observation data. The photometric accuracy is typically ~0.02 mag for LUT
10 mag stars (30 s exposure), with errors come from background noises,
residuals of stray light removing, and flat fielding related errors. The
accuracy degrades to be ~0.2 mag for stars of 13.5 mag which is the 5{\sigma}
detection limit of LUT.Comment: 10 pages, 7 figures, 4 tables. Minor changes and some expounding
words added. Version accepted for publication in Astrophysics and Space
Science (Ap&SS
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