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Composites of Titanium (IV) oxide combined with montmorillonite (MMT) with various TiO2/MMT were prepared for photocatalysis application. The prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and diffuse reflectance UV–visible spectroscopy. The main influential factors such as the TiO2/MMT dose, calcined temperature and pH value of the solution were studied. The main intermediates of phenol degradation were determined by High Performance Liquid Chromatography (HPLC). The results showed that the average size of TiO2 nanoparticles was decreased from 22.51 nm to 10.66 nm through the immobilization on MMT. The components in the interlayer domain were replaced by titanium pillars, and the pillaring reaction proceeded in the interlayer domain, and the basic skeleton of MMT was unchanged, and also TiO2 was dispersed on the surface of the MMT. When the initial concentration of phenol is 10 mg/L, the phenol solution pH is 6 and the UV light irradiation time is 240 min, the phenol degradation rate of 30%TiO2/MMT composite is 89.8%, which is better than MMT (11.5%) and pure TiO2 (58.8%). It shows that TiO2 loaded on MMT improves its photocatalytic activity. The phenol reaction process detected by HPLC showed that it had undergone through hydroquinone and benzoquinone, and finally converted into maleic acid and carbon dioxide and small molecules. The possible photocatalysis mechanism is presented.

The controversial tetrahedral intermediate of the reaction between acetyl chloride and ethanol was detected using novel methodology. The results demonstrate that the reaction proceeds via an addition/elimination mechanism.

Understanding the fundamental mechanisms of chemical reactions is of great interest to scientists working in many fields as it enables the rationalization, prediction, and design of reactions. Many chemical processes involve the formation of short-lived reaction intermediates, most of which cannot be isolated and are challenging to detect. One such intermediate is the tetrahedral intermediate often proposed to be generated upon the reactions of acetyl chlorides with simple alcohols

BACKGROUND Variations in the methylene tetrahydrofolate reductase (MTHFR) gene have been reported as risk factors for numerous conditions, including cardiovascular disease, thrombophilia, stroke, hypertension and pregnancy-related complications. Moreover, it was reported there is an association between breast cancer and mutations in MTHFR-C677T. However, whether there is an association between MTHFR gene polymorphism and granulomatous lobular mastitis or not has been rarely investigated. AIM To analyze the association between MTHFR gene polymorphism and granulomatous lobular mastitis. METHODS Fifty-one patients with granulomatous lobular mastitis admitted to The First Hospital of Kunming were selected as study samples. Their hospitalization time ranged from February 2018 to February 2019. The 51 patients were included in the experimental group, and another 51 women who underwent physical examination at The First Hospital of Kunming in the same period were included in the control group. Deoxyribonucleic acid and MTFR genetic polymorphism testing were performed in each group. The association between MTHFR gene polymorphism and granulomatous lobular mastitis was observed. RESULTS There were significant differences in genotype frequency and allele frequency of C/C and C/T between the experimental group and the control group (all P < 0.05). However, there was no significant difference in frequency of T/T genotype between the two groups (P > 0.05). In addition, there was no significant difference in genotype frequency and allele frequency of A/A, A/C and C/C between the two groups (P > 0.05). CONCLUSION MTHFR gene C677T locus polymorphism is closely related to granulomatous lobular mastitis.

Composites of titanium (IV) oxide combined with montmorillonite (MMT) with various TiO

Laser-induced acoustic desorption (LIAD) enables the desorption of nonvolatile and/or thermally labile neutral compounds, such as asphaltenes, saturated hydrocarbons in base-oil fractions and biomolecules, from a metal surface into a mass spectrometer. This is a “gentle” evaporation technique and causes minimal fragmentation to the desorbed neutral molecules, including oligonucleotides and polypeptides. LIAD can be coupled with a wide range of ionization methods to facilitate analysis of the desorbed analytes by using many different types of mass spectrometers, including Fourier transform ion cyclotron resonance, linear quadrupole ion trap and quadrupole time-of-flight instruments. The development and improvement of LIAD remains an active research area with diverse goals such as better desorption efficiencies, minimized analyte fragmentation and greater versatility. This article details the theory, experimental methods, applications, and future directions of LIAD in combination with mass spectrometry.

The practical application of covalent organic frameworks (COFs) membrane still faces major challenges emanated from harsh fabrication condition, non-uniform performance and high production cost. To address these issues, catalysis-interfacial polymerization (catal.IP) was proposed to fabricate oligomer-induced COFs composite membranes , in which two reactive monomers having extremely low concentration (0.6 mM) were in advance pre-reacted to generate oligomers with planar structure and then subsequently grew under the catalysis of acetic acid to form an ultrathin and continuous COFs layer. The as-prepared TpPa (catal.IP), TpBd (catal.IP) and TpDp (catal.IP) membranes exhibited superior permeability of 52~85 L·m-2·h-1·bar-1 and congo red rejection of 93~99%, precisely in consistent with the pore sizes of COFs. The catal.IP technique would not only inspire the fabrication of COFs composite membranes with a greater variety but also make their scale-up and application feasible and economical.

We report herein a gas-phase reactivity study on a para-benzyne cation and its three cyano-substituted, isomeric derivatives performed using a dual-linear quadrupole ion trap mass spectrometer. All four biradicals were found to undergo primary and secondary radical reactions analogous to those observed for the related monoradicals, indicating the presence of two reactive radical sites. The reactivity of all biradicals is substantially lower than that of the related monoradicals, as expected based on the singlet ground states of the biradicals. The cyano-substituted biradicals show substantially greater reactivity than the analogous unsubstituted biradical. The greater reactivity is rationalized by the substantially greater (calculated) electron affinity of the radical sites of the cyano-substituted biradicals, which results in stabilization of their transition states through polar effects. This finding is in contrast to the long-standing thinking that the magnitude of the singlet-triplet splitting controls the reactivity of para-benzynes.

Stream processing applications reduce the latency of batch data pipelines and enable engineers to quickly identify production issues. Many times, a service can log data to distinct streams, even if they relate to the same real-world event (e.g., a search on Facebook's search bar). Furthermore, the logging of related events can appear on the server side with different delay, causing one stream to be significantly behind the other in terms of logged event times for a given log entry. To be able to stitch this information together with low latency , we need to be able to join two different streams where each stream may have its own characteristics regarding the degree in which its data is out-of-order . Doing so in a streaming fashion is challenging as a join operator consumes lots of memory, especially with significant data volumes. This paper describes an end-to-end streaming join service that addresses the challenges above through a streaming join operator that uses an adaptive stream synchronization algorithm that is able to handle the different distributions we observe in real-world streams regarding their event times. This synchronization scheme paces the parsing of new data and reduces overall operator memory footprint while still providing high accuracy. We have integrated this into a streaming SQL system and have successfully reduced the latency of several batch pipelines using this approach.

Mikania micrantha extract (MME) was prepared by reflux extraction method with 40% C2H5OH water solution. The synergistic inhibition effect of MME and potassium iodide (KI) on cold rolled steel (CRS) in 0.50 M H2SO4 solution was studied by weight loss and electrochemical methods for the first time. The CRS surfaces were fully characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). Meanwhile, the main effective compounds in MME were discussed in depth by high performance liquid chromatography (HPLC). The results show that either MME or KI acts as a moderate inhibitor on CRS in 0.50 M H2SO4 solution, and the maximum inhibition efficiency is below 80%. The mixture of MME/KI has a pleasant inhibition performance with the maximum inhibition efficiency of 94.4%. There is an evident synergistic effect between MME and KI, and the corresponding synergism parameter is higher than 1. Regardless of the extra addition of KI, the adsorption of MME obeys the Langmuir adsorption isotherm. The presence of KI enhances the adsorption of MME owing to larger value of adsorption equilibrium constant for MME/KI mixture. MME is a cathodic inhibitor, while MME/KI can be arranged as a mixed-type inhibitor, and the inhibition of both cathodic and anodic reactions is further enhanced by the MME/KI combination. Nyquist diagram mainly exhibits a capacitor loop that is controlled primarily by charge transfer. As the concentration of corrosion inhibitor increases the capacitance arc length gradually increases, especially for MME/KI mixture. The charge transfer resistance increases more than 10 times and shows excellent corrosion inhibition. SEM and AFM clearly confirm that the presence of MME/KI has a significant effect on inhibiting the corrosion of CRS, and the inhibition is expected to follow the order: MME/KI > KI > MME. XPS reveals that the MME/KI mixture can adsorb on steel surface to achieve inhibitive film. Most important, there is also a synergistic inhibition of effective components in MME (chlorogenic acid, ferulic acid) with KI.

The aim of this work is to establish volcanic seismic reflection configuration models in the rift basins of Northeast China from a new perspective, the volcanostratigraphic structure. Accordingly, the volcanostratigraphic structure of an outcrop near the Hailaier Rift Basin was analyzed to understand the characteristics and causal factors of physical boundaries. Further, 3D seismic reflection data and analysis of deep boreholes in the Songliao Rift Basin were used to establish the relationship between volcanic seismic reflection configurations and volcanostratigraphic structures. These studies suggested that in volcanic successions, physical boundaries coincide with volcanic boundaries, and their distributions are controlled by the stacking patterns of volcanic units. Therefore, volcanic seismic reflection configurations can be interpreted in terms of the stacking patterns of volcanic units. These are also referred to as general bedding patterns in volcanostratigraphy. Furthermore, four typical seismic reflection configurations were identified, namely, the chaotic, the parallel continuous, the hummocky, the multi-mound superimposed and the composite. The corresponding interpretation models comprised single massive unit, vertical, intersectional, lateral multi-mound, and composite stacking patterns. The hummocky and composite reflection configurations with intersectional and composite stacking patterns are the most favorable for the exploration of volcanic reservoirs in rift basins.

The Mesozoic rift basins of northeast China are characterized by a significant proportion of basalt due to the progressive emplacement of basalt lava flows. The objective of this study was to construct vesicle distribution models of the basalt lava flow units, including conceptual geological models and thickness models, to understand the architecture of the basalt and the gas reservoir distribution. The conceptual geological models were constructed based on the characteristics of outcropping basalt lava flows, with supplemental seismic data used to extrapolate the lateral extents of large-scale basalt lava flows. The thickness models were constructed using data on the thicknesses of basalt lava flow units and vesicle zones. These data were obtained from 27 units in outcrop and 204 units interpreted from well logs in the basin. The conceptual geological models revealed that the shapes of the basalt lava flow units change from braided to tabular with increasing thickness and that their inner structures can be divided into three vesicle zones: the top vesicle zone, the massive core zone, and the base vesicle zone. The thickness models revealed that trends in the thickness of the top vesicle zone relative to the thickness of the basalt lava flow unit can be expressed using a piecewise function that can be separated into a linear function and a logarithmic function. Similarly, trends in the thickness of the massive core zone and the base vesicle zone relative to the basalt lava flow unit thickness can be expressed by a piecewise linear function. Vesicle distribution models provide an effective means of determining the proportion and distribution of vesicle zones in basalt with limited borehole data. We also constructed a reservoir model based on our vesicle distribution models, and this model revealed that suitable petroleum reservoirs are primarily located in the thinner braided lava flows.

In the process of developing guided munitions, ground test can only verify the performance of integrated navigation system in low dynamic condition, and its costly and risky to use means of authentication such as flight test and throw experiment. This paper proposes a kind of hardware-in-the-loop simulation (HILS) scheme with tri-axial turntable for verifying the performance of navigation system in high dynamic condition. It respectively uses quaternion method and four-sample rotation vector algorithm as attitude updating algorithms for comparison. On the basis of analyzing the characteristics of some tactical missile and the HILS system, the error sources of integrated navigation system in the simulation with turntable and that without turntable are discussed in detail. The results of HILS show that integrated navigation system is of good performance under high dynamic environment; moreover, for the fiber optic gyroscope (FOG) inertial measurement unit (IMU) which outputs angular rate, quaternion method is better than four-sample rotation vector algorithm.

Realtime data processing powers many use cases at Facebook, including realtime reporting of the aggregated, anonymized voice of Facebook users, analytics for mobile applications, and insights for Facebook page administrators. Many companies have developed their own systems; we have a realtime data processing ecosystem at Facebook that handles hundreds of Gigabytes per second across hundreds of data pipelines. Many decisions must be made while designing a realtime stream processing system. In this paper, we identify five important design decisions that affect their ease of use, performance, fault tolerance, scalability, and correctness. We compare the alternative choices for each decision and contrast what we built at Facebook to other published systems. Our main decision was targeting seconds of latency, not milliseconds. Seconds is fast enough for all of the use cases we support and it allows us to use a persistent message bus for data transport. This data transport mechanism then paved the way for fault tolerance, scalability, and multiple options for correctness in our stream processing systems Puma, Swift, and Stylus. We then illustrate how our decisions and systems satisfy our requirements for multiple use cases at Facebook. Finally, we reflect on the lessons we learned as we built and operated these systems.

Four divalent transition metal carboxyarylphosphonates, [Ni(4,4'-bipy)H{sub 2}L{sup 1}(HL{sup 1}){sub 2}(H{sub 2}O){sub 2}].2H{sub 2}O 1, [Ni{sub 2}(4,4'-bipy)(L{sup 2})(OH)(H{sub 2}O){sub 2}].3H{sub 2}O 2, Mn(phen){sub 2}(H{sub 2}L{sup 1}){sub 2}3 and Mn(phen)(HL{sup 2}) 4 (H{sub 3}L{sup 1}=p-H{sub 2}O{sub 3}PCH{sub 2}-C{sub 6}H{sub 4}-COOH, H{sub 3}L{sup 2}=m-H{sub 2}O{sub 3}PCH{sub 2}-C{sub 6}H{sub 4}-COOH, 4,4'-bipy=4,4'-bipyridine, phen=1,10-phenanthroline) were synthesized under hydrothermal conditions. 1 features 1D linear chains built from Ni(II) ions bridging 4,4'-bipy. In 2, neighboring Ni{sub 4} cluster units are connected by pairs of H{sub 3}L{sup 2} ligands to form 1D double-crankshaft chains, which are interconnected by pairs of 4,4'-bipy into 2D sheets. 3 exhibits 2D supramolecular layers via the R{sub 2}{sup 2}(8) ringed hydrogen bonding units. 4 has 1D ladderlike chains, in which the 4-membered rings are cross-linked by the organic moieties of the H{sub 3}L{sup 2} ligands. Additionally, 2D FTIR correlation analysis is applied with thermal and magnetic perturbation to clarify the structural changes of functional groups from H{sub 3}L{sup 1} and H{sub 3}L{sup 2} ligands in the compounds more efficiently. - Graphical abstract: A series of divalent transition metal carboxyarylphosphonate compounds were synthesized under hydrothermal conditions. The figure displays 2D sheet structure with large windows in compound 2.

{[La(trans-DAM)(cis-DAM)(H2O)2](ClO4)·3H2O}n (1), {[La2(trans-DAM)3(H2O)6](OH)3·7H2O}n (2), {[La(trans-DAM)2(H2O)2]Cl·4H2O}n (3), {[Nd(trans-DAM)2(H2O)2]X·3H2O}n (X = ClO4 (4), NO3 (5)), {[Nd(trans-DAM)(cis-DAM)(H2O)2]Cl·5H2O}n (6), and {[Nd(trans-DAM)2(H2O)2]Cl·5H2O}n (7) incorporating a flexible ligand HDAM (N,N′-diacetic acid imidazolium) were prepared in H2O or H2O/DMF (N,N′-dimethylformamide) solvents. Compounds 1 and 2 both contain the same 2D corrugated layers bridged by DAM− with different bridging modes to form different 3D structures, exhibiting tcs and (4,6)-connected topologies, respectively. The structural differences of 1 and 2 lie in the linkages of DAM− between the layers. Compound 3 also possesses a 3D architecture with an ant net, which is pillared by 2D (4,4) fan-shaped layers in an −ABAB− sequence. Compounds 4−6 contain similar 2D layers to 1 and 2. The analogous cationic structures 4 and 5 show a 4-connected sql net and 6 presents a (4,5)-connected network, resulting from the differen...

Five different pretreatment methods, including dry ashing and microwave digestion with four acid systems (HNO3 + H2O2, HNO3 + H2O2 + HF, HNO3 + HClO4 and HNO3 + HClO4 + HF), were employed for digestion of the samples of Rosa rugosa. Nine major and trace elements were determined using ICP-OES method. The addition standard recovery rates indicate that, with the system of HNO3 + HClO4, better results can be obtained for most of the determined elements. With this method, except for Fe, the recovery rates are in the range of 95.4%-104.6%. For Fe, higher recovery rate (99%) was obtained with HNO3 + H2O2 + HF system.

The integral equation (IE) method is commonly used to model time-harmonic electromagnetic (EM) phenomena. One of the major challenges in its application arises in the solution of the resulting ill-conditioned matrix equation. Here, we introduce a new domain decomposition (DD) based iterative method for the IE solution of time-harmonic electromagnetic problems. There are two major ingredients in the proposed IE-DDM: (a) the method is a type of non-overlapping DD method and provides a computationally efficient and effect preconditioner for the dense matrix equation from the IE method. (b) The presented method is very suitable for dealing with multi-scale EM problem. Each sub-domain has its own characteristics length and will be meshed independently from others. Numerical results demonstrate superior performance of the IE-DDM.

At present, the telecom operational enterprises are faced with the problems of how to integrate the existed OSS systems to meet the clients' demands quickly and how to provide end-to-end business services with fewer costs. To achieve these, some new IT methods and technologies are needed by telecom operational enterprises so as to support the operation managements better and make a good collaboration among the telecom service providers, equipment vendors, sales/marketing departments and clients. This paper presents a new service-oriented analysis and design method for the telecom business integration procedures, and provides a common integration platform with service-oriented architecture to support the integration and execution of various heterogeneous legacy OSS systems in a manner of service-oriented business processes