Analysis of A Remote Rainstorm in the Yangtze River Delta Region Caused by Typhoon Mangkhut (2018)

An extraordinary heavy rain event caused by Typhoon Mangkhut occurred in the Yangtze River Delta region on 16 September 2018, with the maximum of 24-h accumulated rainfall at a single station reaching 297 mm. However, numerical models and subjective forecast failed to predict this typhoon remote rainstorm accurately. In this study, multiple observational data, an analysis dataset, and a trajectory model are used to analyze the causes of this severe rainstorm. The results show that the circulation situation provides a favorable large-scale background condition for the generation of the rainstorm. The coupling of the upper-level westerly jet and the low-level southerly jet is beneficial to the development of strong convections. In the rainstorm area there is a positive vorticity center connected to the main body of the typhoon. The cooling and humidifying effect of dry-cold air saturates the formerly unsaturated wet air, leading to the increase of precipitation. Besides, there is a lower-tropospheric moisture transport path connecting the typhoon and the rainstorm area, providing abundant moisture for the development of rainstorms. The backward trajectory simulation shows that the moisture mainly originates from the lower troposphere over the Philippine Sea, the southern South China Sea, and the sea south of the Philippines

Surface Modification of Bentonite with Polymer Brushes and Its Application as an Efficient Adsorbent for the Removal of Hazardous Dye Orange I

Poly(2-(dimethylamino)ethyl methacrylate)-grafted bentonite, marked as Bent-PDMAEMA, was designed and prepared by a surface-initiated atom transfer radical polymerization method for the first time in this study. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermal gravimetric analysis (TGA) were applied to characterize the structure of Bent-PDMAEMA, which resulted in the successful synthesis of Bent-PDMAEMA. As a cationic adsorbent, the designed Bent-PDMAEMA was used to remove dye Orange I from wastewater. The adsorption property of Bent-PDMAEMA for Orange I dye was investigated under different experimental conditions, such as solution pH, initial dye concentration, contact time and temperature. Under the optimum conditions, the adsorption amount of Bent-PDMAEMA for Orange I dye could reach 700 mg·g−1, indicating the potential application of Bent-PDMAEMA for anionic dyes in the treatment of wastewater. Moreover, the experimental data fitted well with the Langmuir model. The adsorption process obeyed pseudo-second-order kinetic process mechanism

Association between serum 25- hydroxyvitamin D and albuminuiria in middle-aged and older Chinese patients with type 2 diabetes

Abstract Objective The objective was to analyze the relationship between serum 25-hydroxy-vitamin D (25(OH)D) level and albuminuiria in middle-aged and older patients with type 2 diabetes of Gansu Province. Methods Data pertaining to 380 in-patients with type 2 diabetes were collected. Subjects were classified groups based on gender,age,25(OH)D,BMI and UACR.Serum 25(OH)D and other clinical characteristics among various UACR groups were compared.The relationship between albuminuiria and 25(OH)D was analyzed. Results Out of the 380 subjects, 83.4%were classified as vitamin D deficiency, 14.5%were classified as vitamin D insufficiency, while 2.1% were classified as vitamin D sufficiency. Among the participants,41% had albuminuria (microalbuminuria,28.7%;macroalbuminuria,12.3%).The prevalence of 25(OH)D deficiency in the albuminuria group(84.6%) was significantly higher than that in the normoalbuminuria group(82.6%)(Mann–Whitney U test:Z = -3.86,P = 0.000); patients with macroalbuminuria had the highest prevalence of 25(OH)D deficiency (91.5%; P < 0.01 versus normoalbuminuria).A binary logistic analysis demonstrated that 25(OH)D were protective factors for albuminuria. Conclusions The prevalence of vitamin D deficiency in patients with albuminuria was overtly higher than that in patients without albuminuria among middle-aged and older adults with type 2 diabetes

Bentonite Modified by Allylamine Polymer for Adsorption of Amido Black 10B

The main object of this work is to remove Amido black 10B using a new type of bentonite-based adsorbent with cationic groups by the modification of polyallyl amines between the interlayers of bentonite. Fourier transform infrared, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy were used to characterize the functionalized bentonite. A series of batch adsorption experiments were performed. The maximum adsorption amount was 144.08 mg g&minus;1 when the pH was 2 and the contact time was 120 min. In addition, the equilibrium isotherm data were analyzed using Langmuir and Freundlich isotherm models, while only the Langmuir model could provide a high correlation. Therefore, this study provided a new functionalized bentonite as a low-cost adsorbent for dye removal from water

Preparation, characterization and application of magnetic Fe3O4-CS for the adsorption of orange I from aqueous solutions.

Fe3O4 (Fe3O4-CS) coated with magnetic chitosan was prepared as an adsorbent for the removal of Orange I from aqueous solutions and characterized by FTIR, XRD, SEM, TEM and TGA measurements. The effects of pH, initial concentration and contact time on the adsorption of Orange I from aqueous solutions were investigated. The decoloration rate was higher than 94% in the initial concentration range of 50-150 mg L(-1) at pH 2.0. The maximum adsorption amount was 183.2 mg g-1 and was obtained at an initial concentration of 400 mg L(-1) at pH 2.0. The adsorption equilibrium was reached in 30 minutes, demonstrating that the obtained adsorbent has the potential for practical application. The equilibrium adsorption isotherm was analyzed by the Freundlich and Langmuir models, and the adsorption kinetics were analyzed by the pseudo-first-order and pseudo-second-order kinetic models. The higher linear correlation coefficients showed that the Langmuir model (R(2) = 0.9995) and pseudo-second-order model (R(2) = 0.9561) offered the better fits

Synthesis of Triblock Polycarboxylate Superplasticizers with Well-Defined Structure and Its Dispersing Performance in β-Hemihydrate Gypsum

In this work, a novel AaBAb-type triblock polycarboxylate superplasticizers (PCEs) with well defined molecular structures were designed and synthesized, firstly, by reversible addition-fragmentation chain transfer (RAFT) polymerization, to explore the structure–property relationship PCEs in the β-hemihydrate gypsum (β-HH) system. Three PCEs with the same molecular weight and different structure were obtained by changing the feed ratio of the RAFT agent, initiator, and monomer. The effect of the chemical structure of PCEs on their dispersing property and water reduction capacity were assessed in gypsum by measuring the flowability of pastes and the adsorption ability of PCEs on gypsum. Results showed that among three PCEs, when the monomer ratio is 5:1 and a:b = 1:1, PCE-1 exhibited a higher working efficiency, verifying the contribution of regulating structural parameters to the improvement in performances of gypsum paste, because PCE-1 showed the strongest binding capacity with calcium ions due to the relatively equal amount of carboxyl groups at both ends. The AaBAb-type PCEs provide a special advantage over the conventional comb polymer to understand the relation between the structure and property of PCEs, and a direction for further development of PCEs of high performance

Nitrogen fixation genetics and regulation in a Pseudomonas stutzeri strain associated with rice.

The Pseudomonas stutzeri strain A1501 (formerly known as Alcaligenes faecalis) fixes nitrogen under microaerobic conditions in the free-living state and colonizes rice endophytically. The authors characterized a region in strain A1501, corresponding to most of the nif genes and the rnf genes, involved in electron transport to nitrogenase in Rhodobacter capsulatus. The region contained three groups of genes arranged in the same order as in Azotobacter vinelandii: (1) nifB fdx ORF3 nifQ ORF5 ORF6; (2) nifLA-rnfABCDGEF-nifY2/nafY; (3) ORF13 ORF12-nifHDK-nifTY ORF1 ORF2-nifEN. Unlike in A. vinelandii, where these genes are not contiguous on the chromosome, but broken into two regions of the genome, the genes characterized here in P. stutzeri are contiguous and present on a 30 kb region in the genome of this organism. Insertion mutagenesis confirmed that most of the nif and the rnf genes in A1501 were essential for nitrogen fixation. Using lacZ fusions it was found that nif and rnf gene expression was under the control of ntrBC, nifLA and rpoN and that the rnf gene products were involved in the regulation of the nitrogen fixation process