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The impedance matching of ultrasonic focusing spherical transducer is one of the primary factors affecting its work efficiency in ultrasonic focusing flow polishing system. To realize the efficient utilization of the vibration energy of the transducer, there are different requirements for the front and rear matching structure of the transducer. That is, the front matching structure should have high transmittance, and the rear matching structure should have high reflectivity. Based on the acoustic impedance matching theory and Kirchhoff's theory, the Influence of the front & back impedance matching structure of spherical focusing ultrasonic transducer to the focus sound pressure is studied theoretically and experimentally. The new matching structure for spherical focusing transducer is proposed based on above research. The experimental result shows that the focus sonic pressure with the new matching structure is increased by 72.03% compared with the traditional structure.

Beta-gallium oxide (β-Ga2O3) thin films were prepared on a MgO (100) substrate under different oxygen flow ratios via magnetron sputtering. X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and UV–visible near-infrared (UV–vis–NIR) analyses were conducted to study how the oxygen flow ratio affected the crystalline quality and the surface topography of the films. Microstructure analysis revealed a clear out-of-plane orientation of β-Ga2O3 (100) || MgO (100). The film deposited under an oxygen flow ratio of 1% presented the optimal single-crystalline structure, while excess oxygen was confirmed to negatively impact the crystallization characteristics of the films. SEM measurements indicated that the increase in the oxygen flow ratio reduced the grain size and RMS roughness. The average transmittance of the β-Ga2O3 films in the visible range exceeded 83%, with a broad luminescence band exhibited at approximately 485 nm in the photoluminescence (PL) spectra.

The landslide at the entrance of a railway tunnel in the southwestern region is relatively large, especially due to earthquakes and other factors, which are prone to severe disasters and threaten the safety of the tunnel. Through the long-term monitoring test and numerical calculation analysis on-site, the mechanism of the influence of the earthquake-induced landslide on the characteristics of the tunnel’s force and deformation is studied. The research results show that the earthquake caused the landslide thrust to increase. Because of the existence of the supporting structure, the landslide thrust was consumed, and the remaining part resulted in the compression failure of the tunnel. During the seismic monitoring period, the stress loss of the antislide pile anchor cable was 3.73% and the stress of the second lining of the tunnel increased by 25%. Under the condition of extreme seismic, shear failure occurred at the vault, bottom, and waist of the right-line tunnel, and the tensile strength of the right-line tunnel reached 93.8% of the limit value. For the weak links of the tunnel structure, dense reinforcement planting and strengthening of concrete strength should be adopted to enhance the safety of the tunnel structure. While designing the supporting structure, the rock-socketing depth of the antislide piles and the number of antislide piles should be considered a priority. The impact of the antislide pile spacing is relatively small.

The construction of single-atom catalysts (SACs) with high single atom densities, favorable electronic structures and fast mass transfer is highly desired. We have utilized metal-triazolate (MET) frameworks, a subclass of metal-organic frameworks (MOFs) with high N content, as precursors since they can enhance the density and regulate the electronic structure of single-atom sites, as well as generate abundant mesopores simultaneously. Fe single atoms dispersed in a hierarchically porous N-doped carbon matrix with high metal content (2.78 wt %) and a FeN4 Cl1 configuration (FeN4 Cl1 /NC), as well as mesopores with a pore:volume ratio of 0.92, were obtained via the pyrolysis of a Zn/Fe-bimetallic MET modified with 4,5-dichloroimidazole. FeN4 Cl1 /NC exhibits excellent oxygen reduction reaction (ORR) activity in both alkaline and acidic electrolytes. Density functional theory calculations confirm that Cl can optimize the adsorption free energy of Fe sites to *OH, thereby promoting the ORR process. The catalyst demonstrates great potential in zinc-air batteries. This strategy selects, designs, and adjusts MOFs as precursors for high-performance SACs.

The development of advanced energy storage systems, such as rechargeable batteries and supercapacitors (SCs), is one of the great challenges related to energy demand with the rapid development of world economy. Herein, a three-dimensional hierarchical porous lignin-derived carbon/WO3 (HPC/WO3) was prepared by carbonization and solvothermal process. This electrode material for supercapacitor can be operated at a wide voltage window range of −0.4 V to 1.0 V. More importantly, 3HPC/WO3 with ultrahigh mass loading (~3.56 mg cm−2) has excellent specific capacitance of 432 F g−1 at 0.5 A g−1 and cycling stability of 86.6% after 10,000 cycles at 10 A g−1. The as-assembled asymmetrical supercapacitor shows an energy density of 34.2 W h kg−1 at a power density of 237 W kg−1 and energy density of 16 W h kg−1 at a power density is 14,300 W kg−1. A solid-state planar micro-supercapacitor (MSC) was fabricated using HPC/WO3 nanocomposites. Moreover, the calculated specific capacity of MSC was 20 mF cm−2 in polyvinyl alcohol–sulfuric acid gel electrolyte. Overall, through the reasonable design of HPC/WO3 nanocomposite materials and the efficient assembly of MSCs, the performance of the device was greatly improved, thus providing a clear strategy for the development of energy storage devices.

Acid mine drainage commonly occupies some pore space after underground coal mining, and this severely depreciates coal pillars, thereby posing a significant risk to mine stability. Considering that such depreciation is reflected in the microstructures of these pillars, in the present study, we propose a static immersion method suitable for coal seam samples immersion in the laboratory. We immersed the No. 2–2 coal seam samples from the Ningtiao Tower Coal Mine in Yulin, Shaanxi Province, in different acid mine drainage solutions and monitored the pH, oxidation–reduction potential (ORP), electrical conductivity (EC), total dissolved solids (TDS) among other water quality parameters for 300 h. After the immersion tests, samples were examined using scanning electron microscopy (SEM). The pH, ORP, EC, and TDS of the prepared acid mine drainage solutions increased significantly as the immersion time increased. Changes in water quality parameters are attributed to the absorption of hydrogen ions by insoluble clay minerals in the coal, which reduced the acidity, increased the pH value, and enhanced the electrical conductivity of the acid mine drainage solutions. SEM analysis reveals differences in the pore characteristics of (pore throat size and orientation) of the coal samples, and these are caused by erosive effects of the acid mine drainage solutions. Pores with throat sizes greater than 10 μ m increased by 95% as the pH of the acid mine drainage solutions decreased, while the dominant pore orientation (60–90°) decreased to the 0–30° or increased to the 150–180° range, thereby increasing their randomness.

Al coatings and Al-Zn coatings were prepared on the surface of Q345B steel after shot peening using supersonic arc spraying technology to improve anti-slip and anti-corrosion properties. The SEM, XRD and EDAX were used to detect the surface morphology, coating structure and phase composition of the two coatings. The anti-slip coefficient and anti-wear performance of the two coatings were detected by the anti-slip coefficient detector and the MRTR friction and wear tester, respectively. The anti-corrosion characteristics of the two coatings were obtained by the electrochemical corrosion workstation. The experimental results showed that the thickness of both coatings is 100μm. The substrate and the coating are mechanically bonded. Under the condition of the test parameters, the anti-slip coefficients of Al coating and Al-Zn coating were 0.717 and 0.823, respectively, satisfying the service requirement of the steel structure. The corrosion potential of the Al-Zn coating was -1.136, which exhibits a good anti-corrosion performance. Under the condition of water, the anti-wear characteristics of Al-Zn were relatively ideal. The wear-resistance of Al-Zn coating is better than that of pure Al coating. In conclusion, Al-Zn coating possesses excellent anti-slip, anti-corrosion and anti-wear characteristics and can be used in large steel structure surface modification.

Nanoporous graphenes (NPGs) have recently attracted huge attention owing to their designable structures and diverse properties. Many important properties of NPGs are determined by their structural regularity and homogeneity. The mass production of NPGs with periodic well-defined pore structures under a solvent-free green synthesis poses a great challenge and is largely unexplored. A facile synthetic strategy of NPGs via pressing organization calcination (POC) of readily available halogenated polycyclic aromatic hydrocarbons is developed. The gram-scale synthesized NPGs have ordered structures and possess well-defined nanopores, which can be easily exfoliated to few layers and oxidized in controllable approaches. After being decorated with oxygen species, the oxidized NPGs with tunable catalytic centers exhibit high activity, selectivity, and stability toward electrochemical hydrogen peroxide generation.

Cross-linked polyaniline (PANI) gel can provide rapid transfer channels for electrons and ions, and self-cross-linked PANI (SC-PANI) electrodes have been previously reported. However, there are few reports on the preparation of free-standing PANI (FS-PANI) electrodes. Hence, new preparation technologies are required for FS-PANI electrodes and their electrochemical performance must be estimated. Moreover, FS-PANI must be compared with SC-PANI to better estimate their performance. In this study, SC-PANI was prepared using p-phenylenediamine (PPD), phytic acid, aniline (An), and ammonium persulfate as the additive, doping acid, monomer, and oxidant, respectively. Then, it was hydrothermally transformed into FS-PANI. The microstructures of SC-PANI and FS-PANI were characterized using scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy, and their electrochemical performances were tested using cyclic voltammetry, galvanostatic charge–discharge (CD) measurement, and electrochemical impedance spectroscopy. When the molar ratio of PPD to An was 0.10, the electrochemical performance of SC-PANI was the best as it achieved the largest specific capacitance (Cs) (403 F/g) and lowest internal resistance. After 2000 CD cycles, Cs remained at 73%. However, the Cs of FS-APNI was 511 F/g and 97% of the initial Cs value was maintained after 2000 CD cycles. This study is expected to provide an effective basis for the future research on free-standing electrode materials for supercapacitors.

Transparent conductive oxide (TCO) semiconductors are attracted considerable attention due to a wide range of applications, such as flat panel display (FPD), touch panels, solar cells, and other optoelectronic devices. Owing to the different carrier conduction paths between n-type and P-type TCOs, the n-type TCO used in TFTs usually have high Ion/Ioff current ratio (>107) and high electron mobility (>10 cm2/V·s), P-type TCO TFTs are both lower than that of n-type one. For complementary circuits design and applications, however, both P-type and n-type semiconductor materials are equally important. For SnO thin films, it is important to adjust the ratio of Sn2+ (SnO P-type) and Sn4+ (SnO2 n-type) in order to modulate the electrical characteristics. In this investigation of post treatment for SnO thin films, both microwave annealing (MWA) and furnace annealing process with 02 ambient are studied. The results show that SnO thin films are optimized at 300 °C, 30 minutes furnace annealing, the P-type SnO/SnO2 thin film shows surface mean roughness 0.168 nm, [Sn2+]/[Sn4+] ratio as 0.838, at least 80% transmittance between 380 nm-700 nm visible light. Withthe results, SnO can be even used to fabricate high performance P-type thin film transistors (TFTs) device for future applications.

The deformation and failure mechanism of cylindrical shells and square plate with pre-formed holes under blast loading were investigated numerically by employing the Ansys 17.0 and Ls-Dyna 971. To calibrate the numerical model, the experiments of square plates with pre-formed circle holes were modeled and the numerical results have a good agreement with the experiment data. The calibrated numerical model was used to study the deformation and failure mechanism of cylindrical shells with pre-formed circle holes subjected to blast loading. The structure response and stress field changing process has been divided into four specific stages and the deformation mechanism has been discussed systematically. The local and global deformation curves, degree of damage, change of stress status and failure modes of cylindrical shell and square plate with pre-formed circular holes are obtained, compared and analyzed, it can be concluded as: (1) The transition of tensile stress fields is due to the geometrical characteristic of pre-formed holes and cylindrical shell with arch configuration; (2) The existence of pre-formed holes not only lead to the increasing of stress concentration around the holes, but also release the stress concentration during whole response process; (3) There are three and two kinds of failure modes for square plate and cylindrical shell with pre-formed holes, respectively. and the standoff distance has a key influence on the forming location of the crack initiating point and the locus of crack propagation; (4) The square plate with pre-formed holes has a better performance than cylindrical shell on blast-resistant capability at a smaller standoff distance, while the influence of pre-formed holes on the reduction of blast-resistant capability of square plate is bigger than that of cylindrical shell.

The carrier recombination was one of the factors limiting the further improvement of the Cu2ZnSnS4 (CZTS) thin film solar cells. In this paper, a proper bandgap structure was designed to solve this problem. The effects of the different bandgap structure on the CZTS thin film solar cells were studied by the solar cell performance simulation software wxAMPS. A graded bandgap structure was designed and optimized. The bandgap with a front bandgap gradient and a flat bandgap gradient had a favorable effect on the CZTS thin film solar cells. Finally, the fill factor (FF) and conversion efficiency (η) of the CZTS thin film solar cell were increased from 36.41% to 42.73% and from 6.85% to 10.03%, respectively. In addition, the effect of donor and acceptor defect densities in CZTS absorber layer near the CdS/CZTS interface on the device performance was studied, η of the CZTS thin film solar cell was increased from 5.99% to 7.55% when the acceptor defect concentration was 1012–1013 cm−3. Moreover, the thicknesses of the CZTS absorber layer were optimized. The FF and η of the CZTS thin film solar cell were increased to 63.41% and 15.04%, respectively.

Infrared small-target detection of a low signal-to-noise ratio (SNR) has been an important research hotspot. Small targets lack texture and detailed information; in addition, the background tends t...

Hybrid catalysts composed of transition metals and nitrogen-doped carbons have been emerging as one of efficient electrocatalysts for electrochemical CO2-to-CO under ambient conditions. Herein, NiO loaded on mesoporous graphene with tunable concentration of pyridinic nitrogen is rationally synthesized by using low-intensity pulsed laser irradiation and pyrolysis treatments. Comprehensive experiments verify that, it is pyridinic N, rather than pyrrolic N, when bonded to Ni, that significantly enhance the electrochemical CO2 reduction reaction performance. The optimized catalyst exhibits a high CO Faradaic efficiency of 87.5% at a low potential of −0.74 V vs. reversible hydrogen electrode, associated with negligible attenuation of continuous operation over 12 h.

A spectrum tunable method is presented for a high-birefringence fiber loop mirror (HiBi-FLM) comb filter with a polarization controller (PC) in the loop, where not only the wavelength of the comb filter can be continuously tuned with peak transmission remaining at unity, but the peak amplitude can be also continuously tuned without wavelength shift. By using the Jones matrix, we theoretically analyze the comb filter. The analytical expressions of the reflectivity and transmissivity are derived in terms of the orientation angles of three waveplates of the PC. The optimum conditions for wavelength and peak amplitude tunable operations are obtained. Our theoretical results show that when the two quarter-waveplate (QWP) angles are optimally set, the PC could act as a phase shifter or a polarization rotator, which empowers the comb filter to be wavelength continuously tunable or to be peak amplitude variable from 0 to 1 by only rotating the half-waveplate (HWP) of the PC. Moreover, the wavelength shift has a linear relationship with the HWP angle. When the two QWP angles are not optimized, PC has a combined effect of a phase shifter and a polarization rotator, leading to a wavelength shift accompanied by a change of the peak amplitude when tuning the HWP. Our theoretical prediction has been verified by experimental results.

To improve the performance of low-carbon MgO–C refractories, the Cr3C2-coated flake graphite was synthesized by molten salt method, then the Cr3C2-coated flake graphite was added to low-carbon MgO–C refractories. In this work, the effects of reaction temperature, Cr/C mole ratio, and holding time on the synthesis of Cr3C2-coated flake graphite were studied. Furthermore, the effect of Cr3C2-coated flake graphite on the physical properties of low-carbon MgO–C refractories was evaluated. The results indicated that when the reaction temperature was 950 °C, Cr/C molar ratio was 1/2 and holding time was 3 h, the synthesized Cr3C2-coated flake graphite had fewer surface micropores and the crystallinity of Cr3C2 grains was high. In addition, the Cr3C2-coated flake graphite exhibited excellent oxidation resistance. MgO–C refractories containing 2 wt% Cr3C2-coated flake graphite exhibited more excellent physical properties. The results of nano CT detection system showed that the addition of Cr3C2-coated flake graphite promoted the densification of MgO–C refractories.

The hot deformation behavior of Ti-Al-Nb-Zr-Mo-Cr titanium alloy has been investigated using a Gleeble-1500D thermal simulation test machine in the temperature range of 855°C~1015°C,at constant strain rate from 0.01 s-1 to 10s-1 and with height reduction of 45%. The flow curves characteristic under different deformation parameters show significant difference. According to the stress-strain curves of the alloy and its stress characteristics, the Arrhenius constitutive equation was obtained. The average activation energy is about 541 kJ/mol in the α+β field, and about 243 kJ/mol in the β field, respectively. Based on the dynamic materials model, the processing map is generated, which shows that the peak efficiency domain appears at the temperature of 874°C~900°C and the strain rate of 0.001 s-1~0.06s-1 with a peak efficiency of 0.58 at about 887°C/0.001s-1.

Municipal solid waste incineration fly ash (MSWIFA) is a kind of hazardous waste. In the recent years, the demand for the disposal of MSWIFA has gradually increased with the increase of its production. The co-processing of MSWIFA in cement kiln has become the future development trend in this field due to the advantages of large disposal capacity, thorough disposal and low secondary pollution. In this paper, the life cycle assessment (LCA) was used to analyze the environmental impact of cement kiln co-processing MSWIFA, and the influence of allocation method of by-products in pretreatment process on calculation results was discussed. The results of analysis on the pretreatment of MSWIFA using the water-washing process showed that the allocation method of by-products will affect the calculation results to a certain extent, especially in the toxicity-related indicators, and for pretreatment process, electricity production process is the key link to causing environmental impact. The environmental analysis for clinker product shows that the contribution ratio of pretreatment process calculated by extended boundary method was 3.33% larger than that of mass allocation method in acidification potential(AP), and 3.32% smaller than that in WCP.

Blast furnace slag has good adsorption performance and can be used to adsorb heavy metal ions in waste liquid. It’s worth studying whether the blast furnace slag absorbing heavy metal ions will pose a potential threat to the environment during the process when used in cement-based materials.This paper has studied the leaching amount of copper ions in the blast furnace slag-cement system was analyzed, and analyzed the leaching kinetics of copper ions. The results showed that the leaching amount of copper ions in the blast furnace slag-cement system that adsorbed copper ions basically met the national standard, and the solidified body age was 28 days,blast furnace slag content 30% is the smallest condition for the amount of copper ion leaching.The leaching model of copper ions in the blast furnace slag-cement system is the Elovich equation, which is a heterogeneous diffusion process. The longer the curing age is the slower the leaching process is completed and do not cause environmental pollution during long-term use.

Based on the analysis of the development situation of China’s cement industry and the BCG Matrix method, this paper classifies and screens 31 energy-saving technologies in China's cement production, and puts forward guiding suggestions for the application of energy-saving technologies for cement enterprises. The screening results show that the “Energy-efficient powder separation technology” and “New low-calcium cement clinker and production technology” are “double-high” technologies with excellent on both screening indicators. The investment energy saving rates are 17.5 tce/10,000 yuan (tons of standard coal equivalent per 10,000 yuan) and 10 tce/10,000 yuan. The promotion ratio increments are 35% and 25%. “Cement clinker energy-saving nitrogen reduction firing technology”, “Fan drive mode adopts high voltage frequency conversion speed control technology”, “Pure low temperature waste heat power generation technology for cement kiln” are “single-high” technologies with excellent on one of screening indicators. The investment energy saving rates are 0.3tce/10,000 yuan, 4.1tce/10,000 yuan, 3.9tce/10,000 yuan respectively. The promotion ratio increments are 19%, 35%, 31.5% respectively.

As one of the pillar industries for social development and economic construction, cement manufacture is energy and carbon-intensive, whose greenhouse gas (GHG) emissions account for more than 6% of total global man-made GHG emission annually. With the growing attention on the problem of global warming, researching and promoting low-carbon manufacturing technologies to reduce GHG emissions have become the main trend in the development of cement industry under the new era. This article sorted out the low-carbon technologies for cement production reported in recent years, introduced the mainstream methods of GHG accounting and assessment such as life cycle assessment (LCA) and carbon footprint analysis (CFA), meanwhile reviewed the articles in the field of low-carbon technology and assessment methods in cement production, moreover, discussed the merits and demerits of various assessment methods and applicable fields, in order to provide suggestions and supports for low-carbon transformation of cement industry.

Slag is widely used as mineral admixtures in cement-based materials by its potential hydration activity. It has the advantage of saving resources and energy, reducing carbon emission, improving the performance of concrete, and plays an increasingly important role in the building materials industry. But the early strength of slag is low, and the industrialization of useful hydration products also need to be activated, so the utilization rate of slag in high grade cement is restricted. The hydration activity of slag depends not only on the content of vitreous in slag, but also on the structure of vitreous slag. To explore slag glass micro composition and structure of its active role, The slag micro-structure was analyzed from the structure levels, and then the factors affecting the activity of slag was evaluated. The potential advantages and disadvantages of some different methods to active slag were discussed such as physical ways, chemical activation method and compound activation way. The existing problems and development direction of improving the activity of slag were summarized , which could provide a valuable reference for the efficient use of slag.

Insulin (INS) is easily degraded when administered orally and loading it into polylactic acid/glycolic acid (PLGA) polymer nanoparticles can enhance the efficacy of the drug. The W/O/W double emulsion solvent volatilization method was adopted to prepare INS-loaded PLGA nanoparticles. The preparation formula of nanoparticles was determined according to the type, concentration, and PLGA concentration of the emulsifier. Then, the morphology, particle size, and drug encapsulation efficiency of nanoparticles were characterized. Phosphate buffered solution (PBS) with pH = 7.4 was utilized as the release medium, and the prepared nanoparticles were analyzed for in vitro release performance. In addition, the rat diabetes model was constructed, and subcutaneous injection of nanoparticle in vitro release solution was performed to observe its hypoglycemic effect, which was used for the treatment of diabetic patients. Patients were rolled into experimental group and control group. The changes of the patients’ HbA1c, blood lipids (total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C)), C peptide, and aminopeptidase N (APN) were observed before and after treatment. Through the test, the appearance of the prepared nanoparticles was round, the average particle size was 416.7 nm, and the INS encapsulation efficiency was (36.82±2.26)%. After 36 h, the cumulative release of INS reached (60.58 ±1.45)%, and then the release rate gradually slowed down. The drug release tended to be balanced after 72 h, and the best hypoglycemic effect was achieved after subcutaneous administration 3 h (P < 0.01). The blood glucose level of the rat diabetes model was greatly decreased after 3 h injection of 36.8 IU/kg PLGA polymer nanoparticles (P < 0.05), and the blood glucose dropped to the lowest at 8 h (P < 0.01), which was only (38.8 ± 3.72)% of the initial blood glucose. HbA1C of diabetic patients increased remarkably after treatment (P < 0.05), TG, TC, and LDL-C in blood lipids decreased, and HDL-C increased, without statistically considerable differences (P > 0.05). The serum APN level increased greatly (P < 0.01). In short, the prepared PLGA polymer nanoparticles can effectively reduce blood glucose, help diabetic patients to relieve the toxicity of high glucose in the body, and improve the secretion function of INS.

The objective of this study was to explore the application value of microbubble contrast materials in the diagnosis of prostate cancer. Firstly, ordinary nano-microbubbles and biotinylated nano-microbubbles were prepared by rotary evaporation method and mechanical vibration method. Then, the biotinylated anti-six-transmembrane prostate epithelial antigen-1 (STQWK-1) antibody was connected with the previously prepared nano-microbubbles with the help of biotin-avidin method, so as to generate a nano-microbubble contrast agent targeting prostate PC3 cells. While the contrast agent was characterized based on the immunofluorescence method, a microscope was applied to observe the in vitro targeting performance of targeted nano-microbubbles on PC3 cells. A prostate PC3 cell nude mouse transplanted tumor model was established, so that the contrast-enhanced ultrasound (CEUS) effect of different contrast agents on transplanted tumor was compared, which were applied in CEUS examination of prostate cancer patients. The results showed that the targeted nano-microbubbles could display circular green fluorescence under the microscope, and the blank nano-microbubbles had no display under the microscope. Both ultrasonic microbubbles were circular and evenly distributed. The in vitro targeting experiments indicated that targeted nano-bubbles could accumulate on the surface of prostate cancer PC3 cells, and tumor transplantation model proved that the targeted contrast agent carrying STQWK-1 antibody had a strong development and enhancement effect. In the diagnosis of prostate cancer patients, the sensitivity (83.3% vs. 52%), specificity (66.7% vs. 36.3%), accuracy (75% vs. 47.2%), and other indicators of the diagnosis of targeted nano-bubbles prepared showed marked advantages compared with routine trans-rectal US (TRUS) diagnosis. The contrast agent prepared in this study could be specifically targeted to prostate PC3 cells in vitro, which had the effect of development and enhancement and had a good diagnostic performance in the diagnosis of prostate cancer.

The demand for sustainable energy has motivated the development of artificial photosynthesis. Yet the catalyst and reaction interface designs for directly fixing permanent gases into liquid fuels are still challenged by sluggish mass transfer and catalytic kinetics at the gas-liquid-solid three-phase boundary. Here, we report that breathable metal-organic framework (MOF) membranes decorated with metal single-atoms (SAs) can synergistically promote the diffusion, adsorption, and activation of gas molecules (e.g. CO2, O2) to boost the photocatalytic conversion of them into liquid fuels. With Ir SAs as active centers, the defect-engineered MOF (e.g. NH2-UiO-66) matrixes can efficiently harvest visible light and sensitize the electronically tailored Ir SAs for reducing CO2 to HCOOH with the high activity of 0.51 mmol gcat-1 h-1 at the conventional three-phase reaction interface. Furthermore, the breathable SA/MOF membranes can directly convert humid CO2 gas into HCOOH at the high-throughput gas-solid interfaces, presenting a near-unity selectivity and an unprecedented activity of 3.38 mmol gcat-1 h-1. Similarly, with Pd SAs as active centers, the SA/MOF membrane can catalyze the O2-to-H2O2 conversion with an ultrahigh activity of 10.4 mmol gcat-1 h-1 under visible light, suggesting the wide applicability of our catalyst and reaction interface designs.

A new leakage-prevention pixel circuit is proposed to maintain the driving capability of its driving thin-film transistors (TFTs) at a low frame rate of 15 Hz for use in active-matrix organic light-emitting diode (AMOLED) displays. The proposed leakage-prevention mechanism generates a compensating leakage current that reduces the source-to-drain voltage of the switching TFT, thereby lessening the fluctuation of the stored driving voltage when the frame rate is reduced from 60 to 15 Hz. Moreover, the proposed circuit can compensate for the threshold voltage variation in low-temperature polycrystalline silicon TFTs (LTPS TFTs) and current–resistance drops in VDD lines. To validate the performance of the compensation and leakage prevention, simulation models based on the measurement of the fabricated LTPS TFTs and an organic light-emitting diode (OLED) are established. The experimental results confirm that the leakage current of the gate node is successfully suppressed from 50.34 to 1.25 pA by the proposed leakage-prevention mechanism. Also, within the long emission period, the highly uniform OLED currents at low, medium, and high gray levels are achieved, verifying the feasibility of the proposed pixel circuit.

A stretchable conductor is one of the key components in soft electronics that allows the seamless integration of electronic devices and sensors on elastic substrates. Its unique advantages of mechanical flexibility and stretchability have enabled a variety of wearable bioelectronic devices that can conformably adapt to curved skin surfaces for long-term health monitoring applications. Here, we report a poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)-based stretchable polymer blend that can be patterned using an inkjet printing process while exhibiting low sheet resistance and accommodating large mechanical deformations. We have systematically studied the effect of various types of polar solvent additives that can help induce phase separation of PEDOT and PSS grains and change the conformation of a PEDOT chain, thereby improving the electrical property of the film by facilitating charge hopping along the percolating PEDOT network. The optimal ink formulation is achieved by adding 5 wt % ethylene glycol into a pristine PEDOT:PSS aqueous solution, which results in a sheet resistance of as low as 58 Ω/□. Elasticity can also be achieved by blending the above solution with the soft polymer poly(ethylene oxide) (PEO). Thin films of PEDOT:PSS/PEO polymer blends patterned by inkjet printing exhibits a low sheet resistance of 84 Ω/□ and can resist up to 50% tensile strain with minimal changes in electrical performance. With its good conductivity and elasticity, we have further demonstrated the use of the polymer blend as stretchable interconnects and stretchable dry electrodes on a thin polydimethylsiloxane (PDMS) substrate for photoplethysmography (PPG) and electrocardiography (ECG) recording applications. This work shows the potential of using a printed stretchable conducting polymer in low-cost wearable sensor patches for smart health applications.

We employ ultra-high vacuum electron microscopy to investigate the interaction of metal nanoparticles through graphene. The nanoparticles attract those on the other side of graphene in the systems of Ag/graphene/Ag and Cu/graphene/Cu. In contrast, the system of Au/graphene/Au manifests the repelling interaction. Our density functional theory calculations demonstrate that for lower electron-affinity metals such as Cu and Ag, the clusters on opposite sides of graphene prefer the same site to share the electron-loss and reduce the energy. While for higher electron-affinity metals such as Au, they prefer to stay away from the clusters on the other side of graphene.

In this study, ten 1-ethyl-3-methylimidazolium ionic liquids are analyzed by X-ray photoelectron spectroscopy. A reliable charge correction method is established based upon the binding energy difference between cationic N 1s and C2 1s. It is found that the Caliphatic 1s component is applicable for charge correction only if the Kamlet-Taft hydrogen bond acceptor ability value is larger than 0.77. The electronic environment of nitrogen and sulfur atoms is demonstrated in detail. The impact of the substituent on the binding energy of P 2p and B 1s is discussed.

Precipitation behavior of P550 steel for non-magnetic drill collars was investigated by microstructure characterization as well as thermodynamic calculation. The results demonstrate that the main precipitate formed at 650–900 °C was cellular Cr2N, and its precipitation depended heavily on the aging temperature. The most sensitive precipitation temperature of cellular Cr2N was 750 °C. At 750 °C, the cellular Cr2N exhibited fast-slow precipitation kinetics with the aging time prolonging. The initial precipitation of cellular Cr2N was governed by the short-range intergranular diffusion of Cr. During long-term aging, its growth was controlled by the long-range bulk diffusion of Cr. In addition, cellular Cr2N induced the precipitation of σ phase ahead of the cell after long period of aging. Increasing the nitrogen content resulted in the increment of both the nucleation site and the driving force for the cellular Cr2N, which jointly promoted its precipitation.

Developing highly active oxygen evolution reaction (OER) electrocatalysts is crucial and highly desirable to improve the efficiency of water electrolysis for H2 fuel generation. In this work, hiera...

A novel process for recovery of tellurium (Te) from spent Te electrolytes by cyclone electrowinning was developed. The effects of current density, electrolysis time, flow rate of the electrolyte (FRE), electrolyte temperature and cathode substrates on current efficiency (CE), tellurium recovery, cell voltage, energy consumption (EC), and surface morphology were systematically investigated. 99.90% of purity Te deposits were obtained while 95.61% of CE was achieved under the optimum conditions: electrolysis time of 24 h, current density of 60 A·m−2, FRE of 300 L·h−1, temperature of 30 °C and cathode substrates of 316L SS. Meanwhile, Te recovery and EC were 82.89% and 1810.58 kWh·t−1, respectively. Furthermore, as the solution after the electrowinning is recyclable, the consumption of reagents and the liquid effluent are minimized. All the parameters indicate that the cyclone electrowinning technology might serve as a promising alternative for recovering Te from spent Te electrolyte.

To improve the performance of an array-based sensing system, a novel one-pot method was designed to prepare multi-optical signal channel gold nanoclusters (MS-AuNCs), including chemiluminescence (CL) and fluorescence (FL). And multi parameters were extracted from the CL and FL spectra of MS-AuNCs to realize the excellent performance of sensing arrays for heavy metal ion differentiation. In this synthetic strategy, 11-mercaptoundecanoic acid (MUA) was used as the capping agent to form Au(I)–thiol complexes first. Then luminol was introduced as a reductant to reduce the Au(I)–thiol complexes and as a chemiluminescent reagent to form MS-AuNCs. Compared with previous methods for preparing luminescent functionalized nanoparticles, the proposed method could obtain functionalized nanoparticles with multi-optical signal channels in one step and is much simple. The obtained MS-AuNCs exhibited excellent CL performance when reacting with hydrogen dioxide. The peak position of the MS-AuNCs FL emission spectra does not shift as increasing excitation wavelengths. The bright orange FL of MS-AuNCs was strong enough to be seen with naked eye. Based on five parameters extracted from the CL and FL spectra of MS-AuNCs, one sensing array was developed for distinguishing heavy metal ions. The sensing strategy could differentiate seven heavy metal ions with different concentrations, including Al3+, Co2+, Cr3+, Cu2+, Hg2+, Pb2+ and Zn2+. Moreover, novel multi-optical signal channel gold nanoclusters were obtained for the first time in this work, which may find more promising applications in fields such as bioassays and bioimaging.

Highly exposed {001} surfaces of ITD-TiO2 and IDT-TiO2 microspheres with a self-assembled hierarchical structure were prepared via an intermittent two-step hydrothermal method. ITD-TiO2 possesses a polycrystalline structure, and the particle size is about 500 nm. The specific surface area of ITD-TiO2 was found to be 199.21 m2 g−1, which is significantly larger than that of P25. ITD-TiO2 exhibited excellent photocatalytic activity; the degradation rate of MO reached 99.0% after UV-light irradiation for 3.0 h and is 63.6% higher than that of P25. The surface photovoltage of IDT-TiO2 heat-treated at 500 °C was 264 μV, which indicates that more carriers can be generated inside the sample during the photocatalytic process. Moreover, the order of adding the titanium source and morphology control agent in this research system is the key factor affecting the morphology of the sample. This is mainly because the hydrolysis and nucleation of tetrabutyl titanate in the precursor solution is affected by diethylenetriamine.