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In this article, the authors analyze the electric fields of the lightning M-component at close distances, taking into account the characteristics of the lightning channel, particularly focusing on the inclination of the channel. The study considers both fast and slow M-component waveforms. The lightning channel characteristics examined include the inclination of the channel, variations in channel length, wave speed, and current attenuation. The authors compare three typical lightning channel geometries: a vertical channel, a fully inclined channel, and an inclined channel with a vertical channel at the bottom. The results demonstrate that the presence of a grounded and vertical channel significantly influences the waveform of the M-component electric fields at close distances. The late-time response of the M-component electric fields is notably affected by the inclination angle, azimuth angle, and current decay. The simulation results are compared to previous studies that investigated different lightning channel geometries. The authors suggest considering both the channel geometry and current exponential decay along the grounded channel to accurately reproduce the M-component electric fields.

In order to reveal the electrostatic enhancement filtration effect of a dual-layer granular bed filter with an external electric field, a coupled numerical model was established, including the flow field, discrete particle field, electric field and particle collision rebound effect, then the electrostatic enhancement filtration effect of each filter layer was calculated and investigated under different filtration velocities, different temperatures and different electric field intensities, respectively. The results show that the grade filtration efficiencies of the upper and lower filter layers decrease with the increase of filtration velocity, the electrostatic enhancement filtration effect of the external electric field on the fine particles is more obvious, the electrostatic enhancement filtration effect of the upper filter layer is greater at low velocity, and the electrostatic enhancement filtration effect of the lower filter layer is greater at high velocity. The grade filtration efficiencies of the upper and lower filter layers decrease with the increase in temperature, and the electrostatic enhancement filtration effect is more obvious at low temperatures. The grade filtration efficiencies of the upper and lower filter layers increase with the increase of electric field intensity.

An electrochemical N2reduction reaction (NRR), as an environmentally benign method to produce NH3, is a suitable alternative to substitute the energy-intensive Haber–Bosch technology. Unfortunately, to date, it is obstructed by the lack of efficient electrocatalysts. Here, a CoS2/MoS2nanocomposite with CoS2nanoparticles decorated on MoS2nanosheets is fabricated and adapted as a catalyst for the NRR. As unveiled by experimental and theoretical results, the strong interaction between CoS2and MoS2modulates interfacial charge distribution with electrons transferring from CoS2to MoS2. Consequently, a local electrophilic region is formed near the CoS2side, which enables effective N2absorption. On the other hand, the nucleophilic area formed near the MoS2side is in favor of breaking stable N≡N, the potential-determining step (*N2→ *N2H) which brings about a much decreased energy barrier than that on pure MoS2. As a result, this catalyst exhibits an excellent NRR performance, NH3yield and Faradaic efficiency of 54.7 μg·h–1·mg–1and 20.8%, respectively, far better than most MoS2-based catalysts.

The asymmetric upper furnace configuration effect (mainly relied on the short upper furnace) and unreasonable burner designs (mainly related to the burner location and burner span on furnace arches) are taken as potential major factors favoring the asymmetric combustion formation in down-fired boilers. To confirm the burner span’s role in this aspect, numerical simulations on coal combustion in a 600 MWesupercritical down-fired boiler that suffered from severe flow-field deflection and asymmetric combustion were carried out at three burner span settings (i.e., CS= 0.387, 0.441, and 0.495), plus full-load industrial-size measurements at the boiler’s design setup CS= 0.441. The boiler’s design setup shows a badly asymmetric combustion performance with poor burnout and high NOxemissions, corresponding to its severely deflected gas/particle flow field. Shortening the burner span to CS= 0.387 greatly improves the flow-field deflection and asymmetric combustion, resulting in a burnout increase and NOxreduction. In contrast, expanding the burner span to CS= 0.495 aggravates asymmetric combustion to gain a worsened furnace performance, with burnout loss and NOxemissions increased. These changes thus confirm the burner span as a major factor favoring asymmetric combustion. With a short upper furnace equipped to aggravate the asymmetric upper furnace configuration effect, a relatively smaller burner span such as CS= 0.387 should be used for alleviating the flow-field deflection and asymmetric combustion if a high air-box pressure can be allowed in long-term operations.

Water seepage in soil is a fundamental problem involving various scientific and engineering fields. According to the literature, low-velocity water seepage in low-permeability porous media, such as clay, does not follow Darcy's law, also known as pre-Darcy flow. The formation of immovable water due to water adsorption on the pore wall is believed to be responsible for the formation of pre-Darcy flow. However, this view lacks direct solid evidence. To investigate the pre-Darcy water flow in clay, head permeability experiments are conducted on six clay samples with different densities. The results indicate that water seepage in clay at low hydraulic gradients does not follow Darcy's law. A clear nonlinear relationship between flow velocity and hydraulic gradient is observed. Water flow in clay can be divided into the pre-Darcy flow and Darcy flow regions by the critical hydraulic gradient, which is 10–12 for the Albic soil with dry density between 1.3 g/cm3and 1.8 g/cm3. According to the disjoining pressure theory, immovable water due to water adsorption on the pore wall is the primary reason for water flow deviating from Darcy's law in clay. The results indicate that the percentage of movable water ranges from 39.7% to 59.3% for the six samples at a hydraulic gradient of 1. As the hydraulic gradient increases, the percentage of moveable water also increases. Additionally, there is a strong correlation between the percentage of movable water and the variation in hydraulic conductivity with the hydraulic gradient. Furthermore, a quantitative relationship between the percentage of movable water and the hydraulic conductivity has been established. The results of this study suggest that water adsorption on the pore wall not only affects the water movability, but is also closely related to the pre-Darcy flow phenomenon in clay.

In order to reveal the residual distribution pattern and obtain a wide range of high-accurate vertical movement field, we systematically analyzed the joint geodetic adjustment with vertical rate parameters (denoted as joint adjustment) issues based on the simulated and actual multi-source vertical data. First of all, 1000 sets of simulated leveling data containing rand noise were constructed and processed. The corresponding adjustment results show that network shape and observation interval are two main factors affecting the reliability of the vertical rates. Particularly, vertical rates of the small loops, internal points and loops with longer intervals are prior to those of large loops, edge points and loops with short intervals, respectively. Subsequently, we developed a Helmert adjustment program, which can jointly process leveling data and space geodetic data. Compared with the single leveling data adjustment (SLDA), the joint adjustment results of leveling data and 500 geodetic observations (including 2–4 mm/yr errors) demonstrate that the Helmert adjustment can reduce the residual distribution range by roughly 46%. Finally, both SLDA and Helmert methods are applied to actual survey data in eastern China. We find that the error of the latter approach is decreased by about 48% compared with the former. In summary, the Helmert adjustment method can significantly improve the reliability and accuracy of vertical movement in large area.

Background: Both thyroid-stimulating immunoglobulins immunoassay (TSI IA) and thyrotrophin receptor antibody immunoassay (TRAb IA) are commonly used for the diagnosis of Graves’ disease (GD). The aim of the present study was to compare the clinical diagnostic performance of these two methods. Methods: Sera were obtained from 1103 subjects presenting a variety of clinical conditions from three centers: 100 subjects with untreated GD, 200 with treated GD, 62 with autoimmune thyroid disease(AIT), 216 with other thyroid diseases (OTHER-T), 214 with non-thyroid autoimmune diseases (NTAD), 191 with other diseases (OD), and 120 healthy subjects (HS). Both TSI and TRAb IAs were performed for all 1013 serum samples. Bioassay was performed for 86 samples whose TSI results were inconsistent the TRAb assay results. Results: Comparing untreated GD patients with the control groups (AIT, NTAD, OTHER-T, OD, and HS) resulted in an area under the curve (AUC) of 0.992 for the TSI IA and 0.989 for the TRAb IA with no statistically significant difference observed between these AUC values (P?=?0.2733). The best TSI CDP (clinical decision point) value was 0.42?IU/L. The differences in sensitivity (100% vs. 95%, P?=?0.7991) and specificity (97.1% vs. 97.6%, P?=?0.9426) between the TSI and TRAb IA were not statistically significant. TSI IA had a higher agreement with the TSI bioassay than TRAb IA. Conclusion: The clinical diagnostic performance of the TSI IA for diagnosing Graves’ disease was very similar to that of the TRAb IA. TSI IA can be used to diagnose GD in the Chinese.

High temperature corrosion of the water wall tube in a 50 MW thermal power plant was investigated which caused several boiler accidents. X-ray diffraction (XRD) and scanning electron microscopy (SEM) equipped with energy dispersive spectrometer (EDS) were used to observe the cross-sectional morphology of the tube and analyze the oxide scales. Results show that the boiler water and the coal quality did not meet the requirements. High temperature corrosion of water wall tubes was attributed to the using of coal which had a higher ash content and lower received lower heating value. Higher dissolved oxygen and incrustation in the boiler water caused serious corrosion at the inner surface of water wall tube, which led to the possibility of decarburization and degradation of the steel. Suitable coal blending and stability of the thermal load were the effective means to prevent the high temperature corrosion of the tube.

A qualitative detection method for EGFRmutations is not sufficient to guide precise targeted therapy in clinical practice. The aim of this study was to explore the relationship between the abundance of EGFRmutations and efficacy of EGFR tyrosine kinase inhibitors (TKIs).

Density functional theory calculations and microkinetic modeling were used to study the decomposition mechanisms of the bio-oil model compound formic acid over a cobalt-stepped surface. Zero-point-energy-corrected activation barriers and reaction energies and the rate and equilibrium constants of various elementary reactions were obtained. Formic acid dissociation likely starts from dehydrogenation and dehydroxylation, with activation barriers of less than 0.5 eV. The generation of an HCOO intermediate is thermodynamically favored, but such a compound is energetically difficult to convert. COOH formation is fast and dominant at low temperatures, and it is converted rapidly after 450 K. The most favorable formic acid decomposition pathway is HCOOH → COOH → CO. Its rate-determining step is CO–OH scission, with an activation barrier of 0.66 eV and strong exothermicity of −1.19 eV.

Combustion-generated hydrogen chloride (HCl) is considered to be a very hazardous acid gaseous pollutant. This paper presents a laboratory study on the dry adsorption of HCl. The experiments were conducted in a dual-layer granular bed filter, at gas temperatures of 500°C–700°C and n(Ca)/n(Cl)molar ratios of 1.0–5.0 using the silver nitrate titration method by dry adsorbent powders Ca(OH)2. Mainly, the adsorption efficiency of HCl and utilization efficiency of Calcium were studied, by varying relevant factors including n(Ca)/n(Cl), temperature, feeding method, water vapor and CO2. With a relatively higher HCl concentration of 1000 ppm, the experimental results revealed that 600°C may be the optimum temperature for HCl adsorption when optimum n(Ca)/n(Cl) was 2.5 in our tests. The results also demonstrated that the feeding at a constant pressure was more effective, and the HCl adsorption efficiency could rapidly reach over 90% with n(Ca)/n(Cl) = 2.5 at 600°C. Furthermore, the HCl adsorption efficiency was found to be slightly promoted by water vapor, while could be impeded by CO2, and the utilization efficiency of calcium could be up to 74.4% without CO2, while was only 36.8% with CO2when n(Ca)/n(Cl) was 2.5 at 600°C.

The study aims to determine the efficacy and feasibility of a novel folate receptor (FR)-based circulating tumor cell (CTC) detection method in the diagnosis of non-small cell lung cancer (NSCLC). CTCs were collected from 3 ml of blood based on negative enrichment by immunomagnetic beads and then labeled by a conjugate of a tumor-specific ligand folate and an oligonucleotide. After washing off redundant conjugates, the bound conjugates were removed and analyzed by quantitative polymerase chain reaction. The captured cells were validated as tumor cells by immunofluorescence staining. In the evaluation of clinical utility, the results showed that the CTC levels of 153 patients with NSCLC were significantly higher than the controls (49 healthy donors and 64 patients with benign lung diseases; P< .001). With a threshold of 8.64 CTC units, the method showed a sensitivity of 73.2% and a specificity of 84.1% in the diagnosis of NSCLC, especially a sensitivity of 67.2% in stage I disease. Compared with the existing clinical biomarkers such as neuron-specific enolase (NSE), carcinoembryonic antigen (CEA), cancer antigen 125 (CA125), cyfra21-1, and squamous cell carcinoma antigen (SCC Ag), the method showed the highest diagnostic efficiency (area under the curve, 0.823; 95% confidence interval, 0.773–0.874). Together, our results demonstrated that FR-positive CTCs were feasible diagnostic biomarkers in patients with NSCLC, as well as in early-stage tumors.

Electrocatalytic nitrogen reduction reaction (eNRR), a substitute process for the conventional Haber–Bosch for NH3production, has drawn tremendous attention due to its merits in mild conditions, abundant reactant sources, low energy consumption, and environmental protection. However, electrocatalysts for eNRR are still subjected to low catalytic activity and selectivity. Herein, we constructed a CoS2/1T-MoS2heterostructure with CoS2nanoparticles uniformly loaded on 1T-MoS2nanosheets and applied it as an eNRR electrocatalyst for the first time. Theoretical calculation suggests that electron transfer from CoS2to 1T-MoS2across their contact interface optimizes the local electronic structure of 1T-MoS2, where the electron-depletion region near CoS2is in favor of accepting lone-pair electrons from N2to enable N2absorption, and the electron-accumulation region near 1T-MoS2is conductive to break inert N≡N triple bonds. Unlike pure 1T-MoS2, the potential-determining step (PDS) demonstrates a significantly lower energy barrier. In addition, the weak interaction between CoS2/1T-MoS2and hydrogen discourages competitive hydrogen evolution reaction. As a result, CoS2/1T-MoS2exhibited noticeably improved eNRR activity and selectivity, with an NH3yield of 59.3 μg h–1mg–1and a high Faradaic efficiency of 26.6%.

Bi1.5Zn1.0Nb1.5O7(BZN) thin films with good surface morphology were prepared on fused quartz substrates by pulsed laser deposition (PLD). The X‐ray diffraction (XRD) analysis and atomic force microscope (AFM) surface morphology measurements were performed on the samples. The XRD pattern demonstrated that the films are cubic pyrochlore structure and well crystallized. The AFM analysis indicated that the films have less rough surface. The fundamental optical constants, such as band gap, the wavelength dependence of the transmittance, and the refractive index, were obtained. The sign and magnitude of both real and imaginary parts of third‐order nonlinear susceptibility χ(3)of the BZN thin films were determined by a single beam Z‐scan technique performed at 1064 nm with a picoseconds laser. The third‐order nonlinear refractive index coefficient γand the nonlinear absorption coefficient βof the BZN thin films are 4.06 × 10−15m2/W and −1.45 × 10−9m/W, respectively. The real part and the imaginary part of the third‐order nonlinear susceptibility χ(3)of the BZN thin films are 6.03 × 10−9and 1.82 × 10−10esu, respectively. The mechanisms of nonlinear refraction and nonlinear absorption were discussed. The results suggest that BZN thin film exhibit large third‐order nonlinear optical properties and be a promising material for applications in nonlinear optical devices.

This paper studies the relations between the great Wenchuan earthquake and the active-quiet periodic characteristics of strong earthquakes, the rhythmic feature of great earthquakes, and the grouped spatial distribution of MS8.0 earthquakes in Chinese mainland. We also studied the relation between the Wenchuan earthquake and the stepwise migration characteristics of MS≥7.0 earthquakes on the North-South seismic belt, the features of the energy releasing acceleration in the active crustal blocks related to the Wenchuan earthquake and the relation between the Wenchuan earthquake and the so called second-arc fault zone. The results can be summarized as follows: ➀ the occurrence of the Wenchuan earthquake was consistent with the active-quiet periodic characteristics of strong earthquakes; ➁ its occurrence is consistent with the features of grouped occurrence of MS8.0 earthquakes and follows the 25 years rhythm (each circulation experiences the same time) of great earthquakes; ➂ the Wenchuan MS8.0 earthquake follows the well known stepwise migration feature of strong earthquakes on the North-South seismic belt; ➃ the location where the Wenchuan MS8.0 earthquake took place has an obvious consistency with the temporal and spatial characteristic of grouped activity of MS≥7.0 strong earthquakes on the second-arc fault zone; ➄ the second-arc fault zone is not only the lower boundary for earthquakes with more than 30 km focal depth, but also looks like a lower boundary for deep substance movement; and ➅ there are obvious seismic accelerations nearby the Qaidam and Qiangtang active crustal blocks (the northern and southern neighbors of the Bayan Har active block, respectively), which agrees with the GPS observation data.

In Capital area of China, many faultdeformational surveying sites were set up sequentiallyfrom 1967. With short leveling, short base line andshort ranging net across fault, a lot of data havebeen accumulated. In 1992, GPS (Global PositioningSystem) measurements were started in China. Two timesof GPS measurements have been made in 1992 and 1995respectively. The International Terrestrial ReferenceFrame 93 and the Precision Ephemeris provided byInternational GPS Geodynamics Service (IGS) fromGlobal GPS tracing network solution are used. In GPSanalysis and data processing, GAMIT software and GLOBKsoftware are used. The results from these two kinds ofdata are discussed. For earthquake risk area judgment,it is of interest to know where is compressional areaand where is tensional area, and generally thecompressional areas are considered as risk area andcalled abnormal area. All the data from shortleveling, short ranging (measured bylaser-range-finder), short base line (measured by baseline tape) and GPS methods can give us the descriptionabout the deformational state of the crust –compressional state or tensional state. The comparisonshows that, some of the two kinds of data areconsistent, a few of them are contradictory, and thenthe results are discussed.

The fabrication of very-small-aperture lasers is demonstrated, and their performance is analyzed. Because of strong optical feedback caused by a gold film on the front facet of the laser, its behavior changes: The threshold current decreases, the density of light inside the laser diode and the redshift effect of the spectra are enhanced, and the laser diode’s lifetime is shorter than that of common laser diodes with large driving current.

The technology of zinc-diffusion to improve catastrophic optical damage (COD) threshold of compressively strained GaInP/AlGaInP quantum well laser diodes has been introduced. After zinc-diffusion, about 20-?m-long region at each facet of laser diode has been formed to serve as the window of the lasing light. As a result, the COD threshold has been significantly improved due to the enlargement of bandgap by the zinc-diffusion induced quantum well intermixing, compared with that of the conventional non-window structure. 40-mW continuous wave output power with the fundamental transverse mode has been realized under room temperature for the 3.5-?m-wide ridge waveguide diode. The operation current is 84 mA and the slope efficiency is 0.74 W/A at 40 mW. The lasing wavelength is 656 nm.

ABSTRACTThe efficacy of current influenza vaccines requires a close antigenic match between circulating and vaccine strains. As such, timely identification of emerging influenza virus antigenic variants is central to the success of influenza vaccination programs. Empirical methods to determine influenza virus antigenic properties are time-consuming and mid-throughput and require live viruses. Here, we present a novel, experimentally validated, computational method for determining influenza virus antigenicity on the basis of hemagglutinin (HA) sequence. This method integrates a bootstrapped ridge regression with antigenic mapping to quantify antigenic distances by using influenza HA1 sequences. Our method was applied to H3N2 seasonal influenza viruses and identified the 13 previously recognized H3N2 antigenic clusters and the antigenic drift event of 2009 that led to a change of the H3N2 vaccine strain.IMPORTANCEThis report supplies a novel method for quantifying antigenic distance and identifying antigenic variants using sequences alone. This method will be useful in influenza vaccine strain selection by significantly reducing the human labor efforts for serological characterization and will increase the likelihood of correct influenza vaccine candidate selection.

Extraction, isolation, and structure elucidation of title compounds (I) are described.

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