828 research outputs found
Preparation and Numerical Modelling of Ceramic Foam Insulation for Energy Saving in Buildings
For the purpose of energy saving in buildings, a foam ceramic insulation (FCI) was prepared by using fly ash (FA) and ceramic waste (CW) as the main raw materials for its matrix part and foam part, respectively. The effects of the sintering temperature and the additive agent on the macroscopic performances were systematically measured and investigated. The experiment results indicate that for the matrix sample 5% quartz addition makes the rupture modulus at 1200°C reach high to 34.28 MPa, while the corresponding water absorption capacity is only 0.83%. In addition, for the foam sample with 1 wt% silicon carbide, the lowest measured bulk density and thermal conductivity at 1200°C are 0.471 g/cm3 and 0.1184 W/(m•K), respectively. Furthermore, the proposed simulation model predicts that the effective thermal conductivity of FCI decreases with the decrease of the bulk density. Moreover, the simulation results calculated by EnergyPlus software indicate that the synthetic FCI can efficiently reduce the building’s heating and cooling loads and exerts excellent energy conservation effect
N-(4-Chlorophenyl)-2-deoxy-α-l-ribopyranosylamine
In the crystal structure of the title compound, C11H14ClNO3, intermolecular hydrogen bonds link molecules in the ab plane, forming layers that stack along the c axis
Protective efficacy of a broadly cross-reactive swine influenza DNA vaccine encoding M2e, cytotoxic T lymphocyte epitope and consensus H3 hemagglutinin
BACKGROUND: Pigs have been implicated as mixing reservoir for the generation of new pandemic influenza strains, control of swine influenza has both veterinary and public health significance. Unlike human influenza vaccines, strains used for commercially available swine influenza vaccines are not regularly replaced, making the vaccines provide limited protection against antigenically diverse viruses. It is therefore necessary to develop broadly protective swine influenza vaccines that are efficacious to both homologous and heterologous virus infections. In this study, two forms of DNA vaccines were constructed, one was made by fusing M2e to consensus H3HA (MHa), which represents the majority of the HA sequences of H3N2 swine influenza viruses. Another was made by fusing M2e and a conserved CTL epitope (NP147-155) to consensus H3HA (MNHa). Their protective efficacies against homologous and heterologous challenges were tested. RESULTS: BALB/c mice were immunized twice by particle-mediated epidermal delivery (gene gun) with the two DNA vaccines. It was shown that the two vaccines elicited substantial antibody responses, and MNHa induced more significant T cell-mediated immune response than MHa did. Then two H3N2 strains representative of different evolutional and antigenic clusters were used to challenge the vaccine-immunized mice (homosubtypic challenge). Results indicated that both of the DNA vaccines prevented homosubtypic virus infections completely. The vaccines’ heterologous protective efficacies were further tested by challenging with a H1N1 swine influenza virus and a reassortant 2009 pandemic strain. It was found that MNHa reduced the lung viral titers significantly in both challenge groups, histopathological observation showed obvious reduction of lung pathogenesis as compared to MHa and control groups. CONCLUSIONS: The combined utility of the consensus HA and the conserved M2e and CTL epitope can confer complete and partial protection against homologous and heterologous challenges, respectively, in mouse model. This may provide a basis for the development of universal swine influenza vaccines
Thermal Stability and Rheological Properties of Polyethylene (PE)/Polyvinylchloride (PVC)/Wood Composites
This paper investigated the thermorheological properties, thermal properties and flame retardant properties of wood-plastic composites (WPCs). With the addition of wood flour (WF), the rheological behavior became complexity. The critical frequency of shear-thinning phenomenon of the melt viscosity was shifted toward lower value. The temperature dependence of elastic modulus, loss modulus became more serious with the addition of WF. The Cole-Cole plot indicated the existence of complex multi-phase structure in the WPC melt. The CONE calorimetry results showed that ammonium polyphosphate (APP) had good flame retardancy through promoting the formation of the intumescent carbon layer. The present study will supply good insight into the optimization of WPC formulation
Light absorption properties of brown carbon over the southeastern Tibetan Plateau
We present a study of the light-absorbing properties of water-soluble brown carbon (WS-BrC) and methanolsoluble brown carbon (MeS-BrC) at a remote site (Lulang, 3326 m above sea level) in the southeastern Tibetan Plateau during the period 2015-2016. The light absorption coefficients at 365 nm (b(abs365)) of WS-BrC and MeS-BrC were the highest during winter and the lowest during monsoon season. MeS-BrC absorbs about 1.5 times higher at 365 nm compared to WS-BrC. The absorption at 550 nm appears lower compared to that of 365 nm for WS-BrC and MeS-BrC, respectively. Higher average value of the absorption Angstrom exponent (AAE, 365-550 nm) was obtained for MeS-BrC (8.2) than that for WS-BrC (6.9). The values of the mass absorption cross section at 365 nm (MAC(365)) indicated that BrC in winter absorbs UV-visible light more efficiently than in monsoon. The results confirm the importance of BrC in contributing to light-absorbing aerosols in this region. The understanding of the light absorption properties of BrC is of great importance, especially in modeling studies for the climate effects and transport of BrC in the Tibetan Plateau. (c) 2017 Elsevier B.V. All rights reserved
3,4-Dicyanophenyl 2,3,4,6-tetra-O-acetyl-α-d-glucopyranoside
The title compound, C22H22N2O10, was prepared by the glycosidation method through nitrite displacement on substituted nitrophthalonitrile. The molecule contains a benzene ring, two nitrile groups and an acetyl-protected d-glucose fragment which adopts a chair conformation. The absolute configuration was determined by the use of d-glucose as starting material. All substituents of the protected sugar are in equatorial positions, with the exclusive presence of the α-anomer. The crystal packing is stabilized by C—H⋯O and C—H⋯N hydrogen-bonding interactions
Maize straw application as an interlayer improves organic carbon and total nitrogen concentrations in the soil profile: A four-year experiment in a saline soil
Soil salinization is a critical environmental issue restricting agricultural production. Deep return of straw to the soil as an interlayer (at 40 cm depth) has been a popular practice to alleviate salt stress. However, the legacy effects of straw added as an interlayer at different rates on soil organic carbon (SOC) and total nitrogen (TN) in saline soils still remain inconclusive. Therefore, a four-year (2015–2018) field experiment was conducted with four levels (i.e., 0, 6, 12 and 18 Mg ha–1) of straw returned as an interlayer. Compared with no straw interlayer (CK), straw addition increased SOC concentration by 14–32 and 11–57% in the 20–40 and 40–60 cm soil layers, respectively. The increases in soil TN concentration (8–22 and 6–34% in the 20–40 and 40–60 cm soil layers, respectively) were lower than that for SOC concentration, which led to increased soil C:N ratio in the 20–60 cm soil depth. Increases in SOC and TN concentrations in the 20–60 cm soil layer with straw addition led to a decrease in stratification ratios (0–20 cm:20–60 cm), which promoted uniform distributions of SOC and TN in the soil profile. Increases in SOC and TN concentrations were associated with soil salinity and moisture regulation and improved sunflower yield. Generally, compared with other treatments, the application of 12 Mg ha–1 straw had higher SOC, TN and C:N ratio, and lower soil stratification ratio in the 2015–2017 period. The results highlighted that legacy effects of straw application as an interlayer were maintained for at least four years, and demonstrated that deep soil straw application had a great potential for improving subsoil fertility in salt-affected soils.publishedVersio
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