Research on the Properties of Wasteforms after Direct Involvement of Uranium-Containing Silica Gel in Glass Network Formation.

Uranium-containing silica gel (UCSG) is a secondary waste generated during the advanced treatment of nuclear wastewater. In order to reduce the growing storage pressure for UCSG, from the perspective of building a borosilicate glass network, UCSG was used to replace SiO2 in the glass-cured formula to directly achieve the immobilization of UCSG. SEM-EDS results showed that uranium was uniformly distributed in the matrix, and the maximum solid solubility of UCSG (two components: silica gel and uranyl ions) in the formula was as high as 55 wt %. At the same time, TG-MS proved that silica gel lost OH groups (down about 4.61 wt %) and formed Si-O-Si bond by condensation. FT-IR and XPS proved a change in the number of Si-O-Si bond, and new Si-O-B and Si-O-Al bond appeared on the spectrum. This was evidence that silica gel could self-involved participate in the construction of glass networks. EPR analysis obtained the changes in the coordination environment of U atom, the U atom decreased spin electrons number in the glass than in uranyl crystals. The glass also has good physical properties (hardness: 6.51 ± 0.23 GPa; density: 2.3977 ± 0.0056 g/cm3) and chemical durability (normalized leaching rate: LRU = 2.34 × 10-4 ± 2.05 × 10-6 g·m2·days-1 after 42 days), this research provided tactics for simple treatment of uranium-containing silica gel in one step.

Methyltransferase-like 3 aggravates endoplasmic reticulum stress in preeclampsia by targeting TMBIM6 in YTHDF2-dependent manner.

BACKGROUND: With the increasing morbidity and mortality of preeclampsia (PE), it has posed a huge challenge to public health. Previous studies have reported endoplasmic reticulum (ER) stress could contribute to trophoblastic dysfunction which was associated with the N6-methyladenosine (m6A) modification by methyltransferase-like 3 (METTL3), resulting in PE. However, little was known about the relationship between METTL3 and ER stress in PE. Thus, in vitro and in vivo studies were performed to clarify the mechanism about how METTL3 affects the trophoblasts under ER stress in PE and to explore a therapeutic approach for PE. METHODS: An ER stress model in HTR-8/SVneo cells and a preeclamptic rat model were used to study the mechanism and explore a therapeutic approach for PE. Western blot, immunohistochemistry, quantitative reverse transcription-polymerase chain reaction (qRT-PCR), and methylated RNA immunoprecipitation (MeRIP)-qPCR were performed to detect the protein, RNA, and methylated transmembrane BAX inhibitor motif containing 6 (TMBIM6) expression levels. The m6A colorimetric and mRNA stability assays were used to measure the m6A levels and TMBIM6 stability, respectively. Short hairpin RNAs (shRNAs) were used to knockdown METTL3 and YTH N6-methyladenosine RNA binding protein 2 (YTHDF2). Flow cytometry and Transwell assays were performed to evaluate the apoptosis and invasion abilities of trophoblasts. RESULTS: Upregulated METTL3 and m6A levels and downregulated TMBIM6 levels were observed in preeclamptic placentas under ER stress. The ER stress model was successfully constructed, and knockdown of METTL3 had a beneficial effect on HTR-8/SVneo cells under ER stress as it decreased the levels of methylated TMBIM6 mRNA. Moreover, overexpression of TMBIM6 was beneficial to HTR-8/SVneo cells under ER stress as it could neutralize the harmful effects of METTL3 overexpression. Similar to the knockdown of METTL3, downregulation of YTHDF2 expression resulted in the increased expression and mRNA stability of TMBIM6. Finally, improved systemic symptoms as well as protected placentas and fetuses were demonstrated in vivo. CONCLUSIONS: METTL3/YTHDF2/TMBIM6 axis exerts a significant role in trophoblast dysfunction resulting in PE while inhibiting METTL3 may provide a novel therapeutic approach for PE.

Instantaneous Real-Time Kinematic Decimeter-Level Positioning with BeiDou Triple-Frequency Signals over Medium Baselines.

Many applications, such as marine navigation, land vehicles location, etc., require real time precise positioning under medium or long baseline conditions. In this contribution, we develop a model of real-time kinematic decimeter-level positioning with BeiDou Navigation Satellite System (BDS) triple-frequency signals over medium distances. The ambiguities of two extra-wide-lane (EWL) combinations are fixed first, and then a wide lane (WL) combination is reformed based on the two EWL combinations for positioning. Theoretical analysis and empirical analysis is given of the ambiguity fixing rate and the positioning accuracy of the presented method. The results indicate that the ambiguity fixing rate can be up to more than 98% when using BDS medium baseline observations, which is much higher than that of dual-frequency Hatch-Melbourne-Wübbena (HMW) method. As for positioning accuracy, decimeter level accuracy can be achieved with this method, which is comparable to that of carrier-smoothed code differential positioning method. Signal interruption simulation experiment indicates that the proposed method can realize fast high-precision positioning whereas the carrier-smoothed code differential positioning method needs several hundreds of seconds for obtaining high precision results. We can conclude that a relatively high accuracy and high fixing rate can be achieved for triple-frequency WL method with single-epoch observations, displaying significant advantage comparing to traditional carrier-smoothed code differential positioning method.

(meso-5,5,7,12,12,14-Hexamethyl-1,4,8,11-tetra-aza-cyclo-tetra-deca-ne)nickel(II) bis-[O,O'-(1,2-phenyl-ene) dithio-phosphate].

In the crystal structure of the title compound, [Ni(C(16)H(36)N(4))](C(6)H(4)O(2)PS(2))(2), the Ni(II) cation is located on a center of inversion and is chelated by the folded tetra-amine macrocycle ligand in a slightly distorted NiN(4) square-planar geometry. Two symmetry-related O,O'-(1,2-phenyl-ene)dithio-phosphate anions are located on either side of the Ni(II) cation, with Ni⋯S of 3.9558 (5) Å, and link to the tetra-amine macrocycle ligand via N-H⋯S hydrogen bonding.

Tris(1,10-phenanthroline)cadmium 3,3'-dicarb-oxy-4,4'-diazenedi-yl-dibenzoate-4,4'-diazenediyldiphthalic acid-methanol (1/0.5/1).

In the title compoud, [Cd(C(12)H(8)N(2))(3)](C(16)H(8)N(2)O(8))·0.5C(16)H(10)N(2)O(8)·CH(3)OH, the Cd(II) atom has a distorted octa-hedral coordination formed by six N atoms from three separate phenanthroline ligands. One of the 4,4'-diazenediyldiphthalic acid mol-ecules is arranged around an inversion center and possesses two -COOH groups, while the other is partially deprotonated and is a dianion for charge balance. It can be noted that, in the undeprotonated acid, the -COOH groups are disordered over two positions by rotation around the C-C bond linking the -COOH group to the phenyl ring. Surprisingly, the H atom is not involved in the disorder. In the dianion, the remaining H atom is located between the two COO groups. These deprotonated and undeprotonated mol-ecules are linked by O-H⋯O hydrogen bonds, forming a chain developing parallel to the [111] direction. The methanol solvent molecule is highly disordered; it was not considered in the final model by elimination of its contribution from the intensity data.

Bis(4'-hy-droxy-biphenyl-4-carboxyl-ato-κO)(1,10-phenanthroline-κN,N')zinc.

In the title compound, [Zn(C(13)H(9)O(3))(2)(C(12)H(8)N(2))], the Zn(II) atom is located on a twofold rotation axis and has a distorted tetra-hedral coordination with two N atoms from the phenanthroline ligand arranged around the twofold axis and two O atoms from two symmetry-related 4'-hy-droxy-biphenyl-4-carboxyl-ate ligands. The mol-ecules are linked by O-H⋯O hydrogen bonds, forming a chain developing parallel to [101].