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An insufficient amount of NH3 (ammonia) will reduce the conversion efficiency of NOx, which may lead to excess NOx emissions, resulting in NH3-SCR failure. In this article, SCR failure caused by a low NH3- NOx ratio is studied systematically by experiments. The main reasons for a low NH3-NOx ratio in SCR include insufficient urea injection, hydrothermal aging of catalysts and urea crystallization. It was found from an insufficient urea injection experiment that with the increase of NH3- NOx ratio, the NOx conversion efficiency of the SCR system increased, but the ammonia leakage also increased. The main influencing factors of NOx conversion efficiency are different under different NH3- NOx ratios. A flow reactor system was used in the catalyst hydrothermal aging experiment to investigate the effect of hydrothermal aging on catalyst activity. After a 24 h hydrothermal aging experiment at 800 °C, the NOx conversion efficiency of the copper-based zeolite catalysts decreased significantly at the boundary of medium and low temperature regions. And the NO2- NOx ratio in the mixture had a significant effect on the catalytic performance. Thermogravimetry coupled to Fourier transform infrared spectroscopy (TG-FTIR) was used to analyze the composition of urea deposits in a urea deposits analysis experiment. It was found that the main components of urea deposits were urea and isocyanic acid (HNCO). Preventing HNCO polymerization, especially the formation of CYA, can decrease the formation of urea deposits.

Selective catalytic reduction (SCR) is one of the main methods used to reduce NOx emissions from diesel engines. Vanadium-based catalysts are widely used in SCR because of their good sulfur resistances and low costs. In this paper, for improving the catalytic performance of aged SCR, experimental and simulation methods were used to study the effects of the aged SCR state, space velocity, and ammonia-to-nitrogen ratio on the NOx conversion efficiency. The experimental results showed that the catalytic performances of the aged SCR state in the low- and medium-temperature regions were not significantly different from that of the fresh SCR, and the degradation in the high-temperature region was significant. In the low- and high-temperature regions, space velocity was an important factor affecting the aged SCR. Increasing the ammonia-to-nitrogen ratio could compensate for the effect of the SCR aging in the low- and medium-temperature regions to some extent.

The durability of V2O5-WO3/TiO2 selective catalytic reduction (SCR) catalysts for heavy-duty diesel engines was evaluated based on 500 h SCR durability tests conducted using B20 fuel (20% v/v biodiesel + 80% v/v petroleum diesel). The fresh and deteriorated SCR catalysts were characterized by X-ray fluorescence, X-ray diffraction, and Brunauer-Emmett-Teller surface area measurements to investigate the deterioration mechanism of the catalysts. The results show that the SCR de-NOx performance is degraded after SCR durability testing, particularly at high engine speeds. The NOx conversion efficiency of the deteriorated SCR catalysts decreases at temperatures above 400 °C but remains high at temperatures between 250 and 400 °C. The catalyst characterization results reveal that the deterioration in the de-NOx performance is not owing to anatase-to-rutile transformation of TiO2, but because of a decrease in the specific surface area and the loss of the catalyst components, which are greater in the front cross section of the SCR than in the rear cross section. For a given catalyst cross section, the decrease in the specific surface area exhibits a positive correlation with the flow rate of the exhaust gas.

Background: Methylglyoxal, a byproduct of diabetes or the consumption of a high-carbohydrate diet, is associated with vascular injury; however, its molecular mechanisms remain unclear. We aimed to systematically characterize molecular profiles and offer unique insights into new disease pathways, thereby contributing to understanding the mechanisms and pathogenesis of vascular injury-related cardiovascular diseases. Methods: Cell survival assays were performed to assess DNA damage; oxidative stress was confirmed by colorimetric assays and quantitative fluorescence, and cyclooxygenase-2 and the mitogen-activated protein kinase pathways were assessed using ELISA. Differentially expressed proteins were quantitated via TMT-based LC-MS/MS and bioinformatics analysis, and confirmed by parallel reaction monitoring. Results: Vascular injury was assessed through colorimetric assays, quantitative fluorescence, ELISA, and survival assays. Of the 4029 proteins identified, 368 were differentially expressed after methylglyoxal treatment, compared with the negative control; 31 were defined as biomarkers or therapeutic targets according to the Gene Ontology Program, Kyoto Encyclopedia of Genes and Genomes, and protein-protein interaction network analyses. Sixteen proteins were significantly (p1.5-fold change) and 15 were dramatically downregulated (Conclusions: The 31 proteins identified as biomarkers or therapeutic targets may contribute to vascular dysfunction through DNA damage, oxidative stress, inflammation, autophagy, hypertension, endothelial dysfunction, vascular remodeling, and the coagulation cascade. Additionally, new disease pathways involving the Wnt, ErBb, and BMP signaling pathways were identified; all provide scope as potential underlying molecular mechanisms. Therefore, the 31 proteins identified warrant further development as new therapeutic or diagnostic targets for vascular diseases.

A gram-stain-negative, aerobic, non-spore-forming, rod-shaped, non-motile bacterium strain R4HLG17T was isolated from Tamarix ramosissima roots growing in Kumtag desert. The strain grew at salinities of 0–16% (w/v) NaCl (optimum 5–6%), pH 5–9 (optimum 7) and at 16–45 °C. Based on 16S rRNA gene sequence similarity, strain R4HLG17T belonged to the family Halomonadaceae and was most closely related to Halomonas lutea DSM 23508T(95.1%), followed by Halotalea alkalilenta AW-7T(94.8%), Salinicola acroporae S4-41T(94.8%), Salinicola halophilus CG4.1T(94.6%), and Larsenimonas salina M1-18T(94.4%). Multilocus sequence analysis (MLSA) based on the partial sequences of 16S rRNA, atpA, gyrB, rpoD, and secA genes indicated that the strain R4HLG17T formed an independent and monophyletic branch related to other genera of Halomonadaceae, supporting its placement as a new genus in this family. The draft genome of strain R4HLG17T was 3.6 Mb with a total G + C content of 55.1%. The average nucleotide identity to Halomonas lutea DSM 23508T was 83.5%. Q-9 was detected as the major respiratory quinone and summed feature 8 (C18:1ω7c/C18:1ω6c), summed feature 3 (C16:1ω7c/C16:1ω6c), and C16:0 as predominant cellular fatty acids. On the basis of chemotaxonomic, phylogenetic, and phenotypic evidence, strain R4HLG17T is concluded to represent a novel species of a new genus within Halomonadaceae, for which the name Phytohalomonas tamaricis gen. nov., sp. nov., is proposed. The type strain is R4HLG17T (=ACCC 19929T=KCTC 52415T).

Strain N5SSJ16T, a Gram-negative-staining, non-spore-forming, rod-shaped, non-motile bacterium, was isolated from Haloxylon ammodendron stems. The strain grew in the presence of 0–4 % (w/v) NaCl (optimum growth in the absence of NaCl), at pH 7–9 (optimum: pH 8) and at 12–50 °C. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain N5SSJ16T was related phylogenetically to Parapedobacter composti 4M40T (96.5 %) and Parapedobacter luteus 4M29T (95.9 %). The cellular fatty acids were iso-C15 : 0, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), summed feature 9 (C16 : 0 10-methyl and/or iso-C17 : 1ω9c) and iso-C17 : 0 3-OH. MK-7 was the respiratory quinone. The main polar lipids were phosphatidylethanolamine, unidentified aminophospholipid and two unknown lipids. The G+C content of the DNA was 45.8 mol%. On the basis of chemotaxonomic, phylogenetic and phenotypic evidence, strain N5SSJ16T represents a novel species of the genus Parapedobacter , for which the name Parapedobacter deserti sp. nov. is proposed. The type strain is N5SSJ16T (=ACCC 19928T=KCTC 52416T).

The multi-roller straightening process of section steel is analyzed by the springback theory of small curvature plane bending. The theoretical analysis results prove the curvature unification in straightening process and clearly reveal the principle of the multi-roller straightening process. The principle can be described as: the initial curvatures are reduced by several times anti-bending; meanwhile the initial curvature differences are diminished and the residual curvatures are unified; finally, the member after curvature unification is straightened by the last anti-bending. With the plastic region ratios becoming larger, the initial curvatures are more easily unified in straightening process. Based on the plastic region ratios and the required number of roller systems for unifying the initial curvatures, the large deformation straightening strategy and the small deformation straightening strategy are redefined. The new definition provides an important theoretical basis for setting reliable reduction rules. Through the theoretical analysis results, a new straightener design philosophy is proposed to improve the straightening quality and further increase the adjustment precision as well as the flexibility of the last roller system. The adjustable end roller emerges as the times required, achieving a good effect in practical application.

The traditional steel structure deformation monitoring generally uses Total Station and GPS to do monitoring quality control, but there are some disadvantages of these methods. Laser radar technology is a new non-contact measurement technology emerged in recent years. It is ideal for installation and slip construction quality monitoring of large-span steel structure. This paper use laser radar technology to monitor large-span steel structure construction, use laser scanner to scan on steel every period of time and collect 3D point cloud data of the feature points after a period of time. Through the comparative analysis of the data and the chart which reflect the amount of deformation of the feature points, it can accurately obtain the result of structural deformation, oblique direction, and the deviation between the actual coordinates and the design coordinates, which provides the most accurate and direct information for the project. Laser radar technology solves the difficult issues such as workload outside the industry and difficulties in visibility of the traditional measurement methods, greatly improves accuracy and efficiency compared to traditional methods, and achieve a high-precision quality control over the construction.

Enormous river basin information has been collected by for high resolution of the physically-based distributed hydrological model, while the scales of computational domain are often restricted by the intensive calculation. The parallel algorithms of physically-based regional hydrologic soil model (P-RHSM) in OpenGeoSys are brought forward in this paper. The object-oriented C++ programming in the model approaches the two objectives: one is data structure organizations including the spatial discretization of the computation domain with nodes density arrangement and solutions communication of temporal variables, the other is computational efficiency by parallel computing. The Message passing interface (MPI) communication is implemented in P-RHSM which is carried out on Linux supported symmetric multiprocessing computers. P-RHSM is applied to Heihe basin in the northwest China. The high-resolution results of temporal soil moisture content distribution, front movement and parallel performance is presented.