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As a secondary Li-ion battery with high energy density, lithium-sulfur (Li-S) batteries possess high potential development prospects. One of the important ingredients to improve the safety and energy density in Li-S batteries is the solid-state electrolyte. However, the poor ionic conductivity largely limits its application for the commercial market. At present, the gel electrolyte prepared by combining the electrolyte or ionic liquid with the all-solid electrolyte is an effective method to solve the low ion conductivity of the solid electrolyte. We present a cross-linked gel polymer electrolyte with fluoroethylene carbonate (FEC) as a solid electrolyte interface (SEI) film formed for Li-S quasi-solid-state batteries, which can be simply synthesized without initiators. This gel polymer electrolyte with FEC as an additive (GPE@FEC) possesses high ionic conductivity (0.830 × 10-3 S/cm at 25 °C and 1.577 × 10-3 S/cm at 85 °C) and extremely high Li-ion transference number (tLi+ = 0.674). In addition, the strong ability toward anchoring polysulfides resulting in the high electrochemical performance of Li-S batteries was confirmed in GPE@FEC by the diffusion experiment, X-ray photoelectron spectroscopy analysis (XPS), and scanning electron microscopy (SEM) mapping of the S element. Such a high ion conductivity (IC) gel polymer electrolyte enables a competitive specific capacity of 940 mAh/g at 0.2C and supreme cycling performance for 180 cycles at 0.5C, which is far beyond that of conventional poly(ethylene oxide)-based quasi-solid-state Li-S batteries.

To study the lateral deformation characteristics of coal under different confining pressures, coal compression experiments with confining pressures of 0 MPa, 3 MPa, 5 MPa, and 7 MPa were conducted under the same loading rate by using the TAW-2000 electrohydraulic servo rock mechanics experimental machine. The results of the study showed the following: at the initial stage of loading, the lateral strain of coal was about 12.22%–46.9% of the axial strain at the elastic deformation stage and 41.18%–64.96% of the axial strain at the inelastic deformation to peak stress stage. Compared with the experiment under 0 MPa confining pressure, the growth rate of the lateral strain of the coal under 3 MPa, 5 MPa, and 7 MPa confining pressures was much smaller than that of the corresponding axial strain. When the coal was damaged under different confining pressures, the lateral strain was maintained at about 0.6 × 10−2. Based on the field verification, we proposed that the lateral strain during the coal failure and the nonlinear region of the lateral axis ratio changing with time can be used as potential parameters for predicting the coal failure.

In this research, we proposed a highly tunable hybrid plasmonic biosensor for identifying molecule fingerprints of proteins in the infrared range. The device is composed of a photonic band-gap structure and a cavity. The plasmonic energy is confined inside the cavity to enhance the light-analyte interactions. A layer of graphene is placed on the bottom surface of the cavity that is filled with analytes for detection. Our device has a high value of effective sensitivity that is defined as the ratio of the resonant frequency shift to the change of effective refractive index when the cavity is loaded with an analyte. The effective refractive index takes into account the effects of both the cavity structure and the optical property of the analyte. Another feature of our device is that a wide-ranging electrical tunability can be realized by applying various values of bias voltage to the graphene. The resonant frequency can be tuned for sensing different analytes without redesigning and refabricating the device. In addition, the graphene tunability can improve the sensitivity in detecting the non-targeted analytes. A prototype was designed based on photonic theory and fabricated via bottom-up lithography techniques. The research results are expected to be beneficial for nanometer-range bio-identifications and infrared optical sensors.

Combining chiral molecules and covalent organic frameworks (COFs) with ordered pores can result in chiral COFs, which may be employed in the fields of chiral chemistry. In this study, we constructed a novel carboxyl-functionalized COF TpBD-3COOH first and then integrated a chiral molecule, heptakis (6-amino-6-deoxy)-β-CD (Am7CD), into TpBD-3COOH to obtain TpBD-Am7CD. Comparing TpBD-3COOH with TpBD-Am7CD, it could be observed that chiral selectivities improved significantly after decorating TpBD-3COOH with Am7CD in the adsorption experiment. Meanwhile, TpBD-Am7CD exhibited similar chiral selective abilities as the previously reported β-CD COF when it was employed to adsorb amino acid enantiomers, while the content of Am7CD was much less than that in β-CD COF. This indicated that the framework of TpBD-3COOH enhanced the chiral selective ability of Am7CD, which would be a great chiral carrier material for further application. This work provides a new insight for establishing materials for application in the chiral recognition field. Besides, TpBD-Am7CD resulted in an insoluble powder, which endowed this material with the possibility to be an adsorbent and a stationary phase in chromatography.

Urea/1-ethyl-3-methylimidazolium chloride (urea-EMIC) was developed to electrodeposit Cu from Cu2O at room temperature. Density, viscosity and conductivity of this urea-EMIC system were obtained. The cyclic voltammograms illustrated that the electroreduction of copper ion (Cu(I) ion) involves a quasi-reversible and one-step single electron transfer process. Chronoamperometric studies showed that the copper electrodeposition proceeds a three-dimensional (3D) progressive model. With an increase in temperature, on voltammograms the onset potentials for copper ion reduction shifted anodically and the diffusion coefficient determined using chronoamperometry increased from 5.40 × 10−11 m2 s−1 at 333 K to 1.02 × 10−10 m2 s−1 at 363 K. Also, potentiostatic electrolysis was conducted on tungsten substrates at − 0.65 V (vs. Ag) and 363 K. Then spherical metallic copper electrodeposits were obtained.

The continuous growth of the solid-electrolyte interface (SEI) and material crushing are the fundamental issues that hinder the application of Ge anodes in lithium-ion batteries. Solving Ge deformation crushing during discharge/charge cycles is challenging using conventional carbon coating modification methods. Due to the chemical stability and high melting point of carbon (3500 °C), Ge/carbon hybridization at the atomic level is challenging. By selecting a suitable carbon source and introducing an active medium, we have achieved the Ge/carbon doping at the atom-level, and this Ge/carbon anode shows excellent electrochemical performance. The reversible capacity is maintained at 1127 mAh g-1 after 1000 cycles (2 A g-1 (2-71 cycles), 4 A g-1 (72-1000 cycles)) with a retention of 84 % compared to the second cycle. The thickness of the SEI is only 17.4 nm after 1000 cycles. The excellent electrochemical performance and stable SEI fully reflect the application potential of this material.

To electrochemically extract Pb from PbO at room temperature, a new electrolyte, urea−1-ethyl-3- methylimidazolium fluoride (urea−[EMIM]F), was synthesized to dissolve PbO. Afterwards, the electrochemical behavior of Pb in this electrolyte was studied. The density, viscosity and conductivity of this electrolyte were investigated before electroextraction. The electrochemical behavior of Pb in the urea−[EMIM]F system was recorded via cyclic voltammograms, chronoamperometry and potentiostatic electrolysis. The results illustrate that Pb can be electrochemically extracted from PbO in this system at room temperature and that Pb reduction involves a quasireversible process and follows a one-step and two-electron transfer process. The reduction of Pb proceeds with a three-dimensional (3D) progressive model. With an increase in temperature, the onset potentials for Pb reduction shift anodically. The diffusion coefficient of Pb(II) is determined to be 6.88×10−10 cm2/s at 353 K. Additionally, spherical Pb particles are obtained after electrodeposition in the urea−[EMIM]F system via potentiostatic electrolysis.

A terahertz (THz) dielectric property characterization method based on a unified single oscillator model has been developed and applied to a variety of multi-component silicate oxide glasses. The experimental values of dielectric constant determined by THz time-domain spectroscopy (TDS) in the sub-THz region have been confirmed to agree well with the values calculated by the single oscillator model which incorporates the local field effects and the material’s ionicity. This has provided a unified formulation that enables systematic determination of the key physical parameters solely from the high-frequency (optical) and low-frequency (sub-THz) dielectric constants and characteristic resonance frequency in the (sub-)THz region. The low-frequency dielectric constant has been demonstrated to be fully determined by a single parameter of the microscopic total susceptibility. Also, the polarization ionicity, which is defined by the ionic fraction in the microscopic total susceptibility, has been found to be a good indicator to represent the ionic nature of the material. Through this analysis, an increasing trend of the effective ionic charge has been found in high-dielectric constant glasses such as oxyfluorosilicate glasses, and the physical mechanism of their dielectric constant enhancement has been discussed. The present method is expected to be applied to design and characterize dielectric properties of a wide range of multi-component glasses and other isotropic, insulating materials.

This article presents a digital ultraviolet (UV) beam lithography system for fabricating microstructures of arbitrary patterns on a roller mold. This roller mold can then be used in roller imprinting for fast and large-area replication of microstructures on substrates. This digital optomechanical system consists of a UV light source, a digital micromirror device (DMD) and its electronic controller, a high-precision image lens, a fiber array integrated with microlenses on both ends, and a two-axis ( x – θ ) servo-controlled motion stage. It exposes a photoresist (PR) layer coated on the cylindrical surface of a roller with a linear array of 192 small UV spots focused by a microlens/fiber array. On the other end of the fibers, UV light is fed by DMD's micromirrors so that the UV light can be dynamically modulated. Finally, by synchronizing the electronics of DMD chip and the mechanical movement (rotation and translation) of the roller, one can achieve arbitrary UV patterning on the roller's PR layer in a digital and maskless manner. This system can successfully achieve UV patterning with a smallest linewidth of 8 μ m, a pattern resolution of 2.5 μ m, and a total patterning width of 192 mm on a roller with a diameter of 100 mm.

A ternary biochar/vanadium pentoxide/graphite like carbon nitride (BC/V2O5/g-C3N4 denoted BC/VO/CN) composite was prepared by a simple hydrothermal method and its photocatalytic performance was investigated under simulated solar irradiation. The BC/VO/CN was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, UV-vis diffuse reflectance spectroscopy, and photoluminescence spectroscopy. Within the BC/VO/CN composites VO nanoparticles were highly crystalline and intertwined with the lamellas of CN, resulting in the formation of well-defined Z-type heterostructures. The photocatalytic activity was evaluated using Rhodamine B as a model pollutant. Under simulated solar (230–780 nm) irradiation the as-prepared BC/VO/CN hybrid materials demonstrated highly improved photocatalytic activity compared to CN, VO and VO/CN. The cause of the solar enhancement could be ascribed to the formation of Z-type heterojunctions between VO and CN, which promoted faster electron–hole separation and more efficient charge transfer. BC, as an electron transfer medium, accelerated the transfer of photogenerated charge carriers and inhibited their recombination.

Lithium metal anode provides a direction for the development of high-energy-density lithium ion batteries. In order to solve lithium dendritic growth and low Coulombic efficiency in lithium plating/stripping process, designing a three-dimensional (3D) host structure is a feasible solution. Herein, carbon-rich conjugated framework poly(1,3,5-triethynylbenzene) in-situ coated copper nanowires on copper foam is constructed as 3D lithium host, which effectively endows low nucleation overpotential, smooth lithium deposition, and improved cycle stability. The well-designed 3D host structure could achieve high Coulombic efficiency over 99% for 150 cycles and reversible lithium plating/stripping stability over 800 h at 2 mA cm-2. This work highlights the interface modification strategy, and proposes a feasible route for 3D host structure design in the development of lithium metal anode.

Raman spectra are molecule specific, and their peaks in the fingerprint region (200-2000 cm−1) are often sufficient for material identification. High-wavenumber signals (> 2000 cm−1) are rare in inorganic material but rich in organic materials containing light hydrogen atoms. Reports on high-wavenumber (HW) Raman signals are far less than fingerprint signals. This could be partially attributed to the difficulty obtaining HW Raman signals, especially from biological materials containing fluorescent proteins. The development and the availability of InGaAs array and the near-infrared (NIR) laser enabled the acquisition of distinct HW Raman from bio-materials. In this chapter, we will introduce recent applications of HW Raman spectroscopy on different materials, especially on biological tissues. Raman instrumentation based on multiple lasers or multiple spectrometers will also be discussed.

Bilayer barium titanate (BaTiO3, BTO)/bismuth ferrite (BiFeO3, BFO) capacitive devices were fabricated and systematically analyzed from the aspects of thin-film material crystallography and electrical characterization. The tetragonal phase (T) of BTO with the reducing thickness (150 nm) was demonstrated through carefully adjusting the conditions of sputtering process and post-thermal treatments. The thickness dependence of polarization, energy density, permittivity, and leakage current was investigated in the BTO/BFO bilayer system. It showed that 150-nm BFO film is an optimal thickness, which led to the substantial increase in energy density up to 920 mJ/cm3 with the charge/discharge efficiency of 79.7% at 10 V. The permittivity of 150-nm BFO bilayer device was found to be 258, which is much higher than the single -layer BFO and other BTO/BFO devices with different BFO thicknesses. Leakage current could be reduced by three orders with the increasing thickness of BFO layer from 30 to 225 nm. In addition, the leakage current of BTO/BFO bilayer capacitors was 102 times lower than BFO single layer with the same total thickness. The result showed that the leakage current of BFO material could be significantly reduced in the bilayer system. The performance of BTO/BFO bilayer capacitors indicates that it is a promising technique for the implementation of nanoscale, lead-free, and nonelectrochemical thin-film energy storage-related applications.

Silica-based controlled-release materials show great potential for medical therapy applications, but have also been introduced into the area of metal anti-corrosion. However, few silica—based contr...

In this paper, the thermal performance of thermosyphon with a flat evaporating surface combined with different sizes of micro pillars was investigated by experimental method. Micro pillars with different sizes were fabricated on the surface of the evaporator bottom plate to enhance heat exchange. An experimental platform was designed and constructed to test the heat transfer performance of the thermosyphon. Deionized water was chosen as the working fluid and the condenser section of the thermosyphon was cooled using water cooling. The operating pressure of the thermosyphon was measured by a pressure sensor to obtain the corresponding saturated temperature. The wall temperature of the evaporator section, the operating pressure of the thermosyphon, as well as the temperature and flow rate of the cooling water were detected for different heat flux. The evaporator section wall temperature (ESWT) and evaporator section wall superheat (ESWS) of the thermosyphon with a smooth evaporator bottom plate (THSE) or micro pillars on the evaporator bottom plate(THMPE)were comparatively studied. ESWT and ESWS of the thermosyphon with micro pillars were much lower than those of THSE. Generally, when the micro-pillar width was constant, heat transfer was intensified with increasing micro-pillar height. When the micro-pillar width was 200 μm, ESWT of the thermosyphon with a micro-pillar height of 200 μm was 12.1 °C higher than that of thermosyphon with a micro-pillar height of 800 μm at a heat flux of 68.6 W/cm2. When the micro-pillar heights were 200 μm and 400 μm, the variations of micro-pillar width evidently reduced ESWT. However, when the micro-pillar height was 600 μm and 800 μm, the variations of micro-pillar width barely affected ESWT due to the capillarity and disturbance of bubbles motion caused by micro-pillar changes. At a smaller micro-pillar width, the thermosyphon with higher micro pillars had lower ESWS. When the heights of micro pillars were 200 μm and 400 μm, the increase of micro-pillar width was conducive to reducing ESWS. When the heights of micro pillars were 600 μm and 800 μm, a smaller micro-pillar width better reduced ESWS of the thermosyphon.

Dielectric properties of oxyfluorosilicate (OFS) glasses have been characterized using Terahertz (THz)-time domain spectroscopy in the sub-THz region as well as optical reflection measurement. OFS glass containing 20 mol% of Nb2O5, which is termed ZNbKLSNd glass, has the highest refractive index of 3.70 in the sub-THz region. The THz and optical refractive indices of various silicate oxide glasses, including OFS glasses, have been confirmed to be correlated by a unified relationship utilizing a parameter defined by the ratio of ionic to electronic polarizability. Additionally, the frequency dependence of the THz dielectric constant has been interpreted by a single oscillator model for all silicate oxide glasses including OFS glasses. On the basis of the present unified dielectric model, the very high refractive index of ZNbKLSNd glass has been attributed to the lowering of oscillator resonance wavelength originated from the incorporation of Nb2O5 intermediate network former.

Latent heat thermal energy storage (LHTES) systems have gained significant attention recently owing to their high energy-storage-density per unit volume and nearly isothermal behavior during the phase-change process. This study numerically investigates the melting performance of a phase-change material (PCM: Ba(OH)2·8H2O) in a triplex tube heat exchanger (TTHX). First, the physical and mathematical models of the TTHX are established. Then, the governing equations are discretized by the finite volume method (FVM). Finally, numerical calculations are carried out by implementing the developed numerical algorithm in FORTRAN computer code. The results reveal that the inlet temperature and flow state of the heat transfer fluid (HTF) significantly influences the PCM melting performance and exergy efficiency ratio of the investigated TTHX. A higher inlet temperature and turbulent state of the HTF can accelerate the phase-change process. However, increasing the mass flow rate of the HTF decreases the exergy efficiency ratio of the investigated TTHX. In conclusion, considering both the melting time and exergy efficiency ratio, increasing the HTF inlet temperature to a certain extent and reducing the mass flow rate of the HTF in the turbulent state can improve the thermal performance of the investigated TTHX.

Water plays a critical role in dental tissues including enamel and dentin. The characterization of water structure analysis was primarily conducted by nuclear magnetic resonance. Raman spectroscopy is a powerful analytic technology with capability for structure analysis in materials. However, acquiring high wavenumber Raman signals from dental tissues was challenging due to either the fluorescence interference under laser illumination or reduced sensitivity of CCD detectors. In this study, we demonstrate a pilot research on high wavenumber Raman analysis in dental tissues using a customized Raman spectrometer based on an InGaAs detector. A signal located at 3570 cm(−1) is found dominating the O-H region Raman spectra of enamel but is barely detectable from dentin. The profiles of the high wavenumber region Raman spectra changes with the locations in enamel, as well as the polarization of the excitation laser beam. The results suggest that the size or crystallinity differences of hydroxyapatite crystals are the main cause of the spectral variation from dentin to enamel, and could be partially responsible for the variation among different locations in enamel.

The thermal‐hydraulic performance of printed circuit heat exchanger (PCHE) through an experimental vaporization process of supercritical nitrogen was investigated. The inlet temperature of supercritical nitrogen was controlled between 113 K and 129 K, while its pressure was controlled between 4.5 MPa and 6 MPa. The mass of supercritical nitrogen corresponds to the turbulent state on the cold side of PCHE, which was maintained at 299.94 kg/h. A numerical processing of the same supercritical nitrogen flow through a single channel of PCHE cold side was presented. The numerical results were validated by comparison with the experimental data. Both experimental and numerical results showed that the increased inlet supercritical nitrogen pressure improved the heat transfer performance and pressure drop decreased with increasing the pressure at the PCHE cold side. Furthermore, the Fanning friction coefficient (f) and the Nusselt number (Nu) of supercritical nitrogen flow obtained by numerical simulation and empirical correlation were compared.

Obtaining good quality protein crystals is still desirable for high resolution structural determination of the proteins using crystallography. The crystal quality is affected by the growth environment and growth methods. As frequently used methods in practical protein crystallization, sitting and hanging-drop methods are seldom compared in terms of crystal quality in the literatures. We performed a systematic comparison on the quality of the protein crystals grown in sitting and hanging-drop methods using different crystallization plates: cross-diffusion microbatch plate (CDM SD: CDM plate, sitting drop method; CDM HD: CDM plate, hanging drop method), traditional sitting and hanging-drop vapor diffusion plates (T SD: traditional plate, sitting drop method; and T HD: traditional plate, hanging drop method). Five different proteins, proteinase K (prk), lysozyme (lys), concanavalin A VI (con), catalase (cat) and α-Chymotrypsinogen A II (chy), were used. The crystal quality was compared in terms of the resolution limit, mosaicity and Wilson plot B factor. It was found that the crystals grown in CDM plate using the hanging drop method (CDM HD) exhibited the best morphology and the best crystal quality. X-ray diffraction tests showed that the CDM plate using hanging drop method is indeed a practical and useful method for obtaining high-quality protein crystals.

In this paper, a cholesterol biosensor is developed using a single-mode fiber (SMF) and a hollow core fiber (HCF) to detect and measure the cholesterol concentration in the human body. The sensitivity of an SMF-HCF structure (sensor probe) has been enhanced by the localized surface plasmon resonance (LSPR) technique using the gold nanoparticles (AuNPs) of 11± 0.5 nm particle size. Furthermore, sensor probe was functionalized with cholesterol oxidase (ChOx) enzyme to increase the selectivity of biosensor. The synthesis of AuNPs is confirmed by a UV-visible spectrophotometer, transmission electron microscope (TEM), and energy-dispersive X-ray spectroscopy (EDS). Furthermore, the coating of AuNPs over an optical fiber is verified by scanning electron microscope (SEM). The linearity range and detection limit of the proposed sensor are 50 nM– $1~\mu \text{M}$ and 25.5 nM, respectively. The selectivity of biosensor has been determined with the 10-mM concentration of different solutions of cholesterol, glucose, urea, ascorbic acid, L-cysteine, and galactose that are generally present in serum.

With merit of nano size, meso-porous structure and graphene coating, a nonstoichiometric silicon oxides, SiOx, composited material was fabricated into a newly developed lithium ion supercapacitor as negative electrode in this study. After characterization of this SiOx based material through XRD, XPS, SEM, EDS, TEM, TG and nitrogen adsorption/desorption isotherm, it was coupled with porous active carbon, which acted as positive electrode, to construct a lithium ion hybrid supercapacitor. The hybrid device then exhibited a high stable capacity of 880 mA h g−1 at the 200 mA g−1 of applied current density. A reversible specific capacity of 328 mA h g−1 is observed after 6000 charge and discharge cycles under 5 A g−1. Furthermore, quite a low, about 4.2 μA, leakage current is also revealed.

In this study, we propose a biochemical sensor that features a photonic cavity integrated with graphene. The tunable hybrid plasmonic-photonic sensor can detect the molecular fingerprints of biochemicals with a small sample volume. The stacking sequence of the device is “ITO grating/graphene/TiO2/Au/Si substrate”, which composes a photonic band gap structure. A defect is created within the ITO gratings to form a resonant cavity. The plasmonic-photonic energy can be confined in the cavity to enhance the interaction between light and the analyte deposited in the cavity. The finite element simulation results indicated that the current sensor exhibits very high values in resonance shift and sensitivity. Moreover, the resonance spectrum with a broad resonance linewidth can identify the molecular vibration bands, which was exemplified by the fingerprint detections of protein and the chemical compound CBP. The sensor possesses an electrical tunability by including a graphene layer, which allowed us to tune the effective refractive index of the cavity to increase the sensor’s sensing performance. In addition, our device admits a phononic bandgap as well, which was exploited to sense the mechanical properties of two particular dried proteins based on the simplified elastic material model instead of using the more realistic viscoelastic model. The dual examinations of the optical and mechanical properties of analytes from a phoxonic sensor can improve the selectivity in analyte detections.

Fabrication of easily recyclable photocatalyst with excellent photocatalytic activity for degradation of organic pollutants in wastewater is highly desirable for practical application. In this study, a novel ternary magnetic photocatalyst BiVO4/Fe3O4/reduced graphene oxide (BiVO4/Fe3O4/rGO) was synthesized via a facile hydrothermal strategy. The BiVO4/Fe3O4 with 0.5 wt% of rGO (BiVO4/Fe3O4/0.5% rGO) exhibited superior activity, degrading greater than 99% Rhodamine B (RhB) after 120 min solar light radiation. The surface morphology and chemical composition of BiVO4/Fe3O4/rGO were studied by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, UV visible diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy. The free radicals scavenging experiments demonstrated that hole (h+) and superoxide radical (O2•−) were the dominant species for RhB degradation over BiVO4/Fe3O4/rGO under solar light. The reusability of this composite catalyst was also investigated after five successive runs under an external magnetic field. The BiVO4/Fe3O4/rGO composite was easily separated, and the recycled catalyst retained high photocatalytic activity. This study demonstrates that catalyst BiVO4/Fe3O4/rGO possessed high dye removal efficiency in water treatment with excellent recyclability from water after use. The current study provides a possibility for more practical and sustainable photocatalytic process.

Quality control (QC) is the most important key issue in the pharmaceutical industry to ensure the quality of drug products. Many analytical instruments and techniques in pharmaceutical analysis are applied to assess the quality and quantity of the drugs. In the current and future trends, a combination of digitization, automation and hyphenation with high throughput on-line performance will be the topics for the future of pharmaceutical QC. The hyphenated analytical techniques have recently received great attention as unique means to solve complex analytical problems in a short period of time. This review article is an update on the recent potential applications of hyphenated technique developed from the coupling of a rapid separation or induction technique (differential scanning calorimetry; DSC) and an on-line spectroscopic (Fourier transform infrared; FTIR) detection technology to carry out an one-step solid-state analysis in pharmaceutical formulation developments, including (1) intramolecular condensation of pharmaceutical polymers, (2) intramolecular cyclization of drugs and sweetener, (3) polymorphic transformation of drugs and excipients, (4) drug-polymer (excipient) interaction, (5) fast cocrystal screening and formation. This simultaneous DSC-FTIR microspectroscopy can also provide an easy and direct method for one-step screening and qualitative detection of drug stability in real time.

The printed circuit heat exchanger (PCHE) with discontinuous fins is a novel type of compact and highly efficient plate heat exchanger, which has superior thermal hydraulic performance. The morphology and characteristics of the flow channel greatly affect the performance of the PCHE. The discontinuous airfoil fins are used in PCHE channel design because they can affect the flow and heat transfer by increasing the heat transfer area and the disturbance in the channel. In this paper, the effects of different staggered distance (Ls) and transverse distance (Lv) of airfoil fin arrangements on the heat transfer and flow of supercritical nitrogen in the PCHE are numerically simulated using ANSYS Fluent. Simulation results and subsequent analysis show that the appropriate decrease in Ls and reduction in Lv between the two rows of fins can improve the convective heat transfer of the PCHE. A fully staggered arrangement of fins (Ls = 1.2) and an appropriate increase in the Lv can mitigate pressure drop. The comprehensive performance of different channel geometries is compared by the performance evaluation criteria (PEC) in this study. It is shown that considering flow resistance and heat transfer, the comprehensive heat transfer performance can be enhanced by properly increasing the staggered distance and the vertical distance between fins. When Ls = 1.2 mm and Lv = 1.25 mm, the PEC value of the staggered channel is the highest, which is 11.6% higher than that of the parallel channel on average.

We demonstrate indium-tin-oxide (ITO) finger-type pattern (FTP) as an effective transparent conducting electrode for terahertz (THz) application. The average transmittance of ITO-FTP is as high as 85% in the frequency range of 0.2–1.2 THz. A pair of fused silica substrates with ITO-FTP was employed for constructing an electrically tunable twisted nematic liquid crystal (LC) based THz phase shifter. The cross-orientation pair of ITO-FTPs served as wavelength-insensitive and transparent electrodes for the LC layer. A maximum phase shift exceeding π/2 at 1.2 THz was demonstrated for a device with a 600-μm-thick LC cell. The required driving voltage for quarter-wave operation and threshold voltage were 5.3 and 0.8 V RMS, respectively. Performance of the THz phase shifter is discussed by defining a figure of merit (FOM) for LC-based THz shifters and compared with previously reported devices.

Thermal barrier coatings (TBCs) consisting of yttria-stabilized zirconia (YSZ) as top coat and NiCrAlY as bond coat were deposited on AZ91D magnesium alloy substrate by atmospheric plasma spraying (APS). In order to improve the stability and prolong the thermal shock life of TBCs, a Ni-P/Al/Ni-P sandwich interlayer between the AZ91D magnesium alloy substrate and the NiCrAlY bond coat was fabricated by electroless plating for Ni-P layer and APS for Al layer. The thermal shock behavior of the YSZ TBCs with the Ni-P/Al/Ni-P sandwich interlayer quenched in water at 400 °C was investigated in detail. The results showed that the thermal shock life of YSZ TBCs with the Ni-P/Al/Ni-P interlayer on the AZ91D substrate was about 226 cycles. The failure of YSZ TBCs in thermal shock test was mainly induced by the corrosion of AZ91D substrate. The results of polarization tests and electrochemical impedance spectroscopy showed that the Ni-P/Al/Ni-P interlayer had better corrosion protection for the magnesium alloy substrate than the Ni-P interlayer, which thus enhanced the thermal shock life nearly two times as compared to that of YSZ TBCs with the Ni-P interlayer.

Mixing time is one of the operational parameters that can affect the rheological and mechanical behaviors of cemented backfill. The objective of this study was to investigate the effect of mixing time on the cemented backfill process. The backfill mixture consisted of a solid waste phosphogypsum (PG), a hydraulic binder, and water. The fresh slurry of backfill was sampled at seven different mixing times (ranging from 5 to 240 min), and its physical properties including apparent viscosity, electrical conductivity, bulk density, air content, bleeding rate, and setting time were measured. The slurry samples were then filled into molds to prepare hardened backfill samples. The pore structure, microstructure, and unconfined compressive strength (UCS) of the hardened backfill samples were determined at different curing ages. The results indicate that mixing time significantly affects the complete process of backfill, from the fresh slurry to the hardened structure. The optimum mixing time was found to be 60 min, under which the backfill slurry exhibited the best properties, including the lowest apparent viscosity, which enabled easier transport. Furthermore, the optimal slurry also showed the lowest air content and the highest bleeding rate, both of which resulted in a low porosity and consequently a high mechanical strength of the hardened backfill structure. On the other hand, outside of the optimum mixing time, either insufficient mixing or overmixing may lower both the fluidity of the slurry and the strength of the hardened backfill. This study therefore demonstrates that the mixing time is an important factor in the design of an easy-delivery and high-strength backfill system.

Printed circuit heat exchanger (PCHE), with the core comprising many mini/microchannels, have been extensively studied, but few works involved two-phase flow. A simplified channel model of PCHE hot side was herein established to numerically explore the heat transfer and condensation flow performance of R22 in minichannels under different conditions. The model was a semicircular minichannel with 0.91 mm hydraulic diameter and 50 mm full length. The heat flux was kept at −77,195 W m − 2 , the inlet pressure was 0.63 MPa and the mass fluxes ranged from 58 to 93 kg m − 2 s − 1 . The condensation flow characteristics along the channel were analyzed. Four flow patterns, i.e., smooth-annular, wavy-annular, slug and bubbly, were noticed at different refrigerant mass fluxes and plotted as a flow pattern map. The effects of import vapor quality from 0.5 to 1 on pressure drop and heat transfer performance were evaluated. The heat transfer performance was optimal at the import vapor quality of 0.7. The impacts of refrigerant mass flux on pressure drop and local condensation heat transfer coefficient were assessed. Intermittent flow enhanced heat transfer. In addition, the correlations for local Nusselt number and Fanning friction factor were presented and compared with numerical data.

White organic light-emitting devices (WOLEDs) were fabricated by using a highly blue fluorescent dye of 4,4’-bis(2,2’-diphenyl vinyl)-1,1’-biphenyl (DPVBi) and a red fluorescent dye of 5H-benzo[ij] quinolizin-9-yl) ethenyl]-4H-pyran-4-ylidene] propane-dinitrile (DCM2), together with a green fluorescent dye of 10-(2-benzothiazolyl)-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H,11H-(1)-benzopyroyran-o(6,7-8-i,j) quinolizin-11-one (C545T). The multilayer WOLEDs does not involve the doping process. The structure of the device is indium tin oxide (ITO)/4,4’,4”-tris{N,-(3-methylphenyl)-N-phenylamin}triphenylamine (m-MTDATA) (55 nm)/ N,N’-bis-(1-naphthyl)-N,N’-diphenyl-1,1’-biph-enyl-4,4’-diamine (NPB) (10 nm)/ DPVBi (8 nm)/ C545T (x nm)/ DPVBi (5 nm)/ DCM2 (y nm)/ tris- (8-hydroxyquinoline) aluminum (Alq3) (60nm)/ LiF (1 nm)/ Al, where the DPVBi is introduced as a spacer. By changing the thicknesses of dual ultrathin layers of C545T and DCM2, the WOLED is obtained. When x=y=0.05, the Commission Internationale de 1’Eclairage (CIE) coordinates of the device change from (0.262 6, 0.351 4) at 4 V to (0.214 7, 0.269 3) at 12 V that are well in the white region. Its maximum luminance is 41400 cd/m2 at 13 V, and the maximum current efficiency and the maximum power efficiency are 7.95 cd/A at 6 V and 5.37 lm/W at 5 V, respectively.

Recently, we developed ultrasmall molybdenum disulfide (MoS2) quantum dots for computed tomography (CT) and multispectral optoacoustic tomography (MSOT) imaging-guided photothermal therapy (PTT). B...

The steel slag is not widely or extensively used because of its poor volume stability and low cementitious activity. In this paper, the solid waste fly ash, quicklime and slag discharged from iron and steel enterprises are used as conditioning components in the experiment. In order to improve the cementitious activity and volume stability of steel slag, the high temperature reconstruction experiment of steel slag was completed. The effects of C/S (2.50~3.14), S/A (4.5~17. 81) on the cementitious activity and volume stability of reconstructed steel slag were investigated by means of the tests of compressive strength, scanning electron microscope, X-ray diffraction, lithofacies test, stability test and so on. The results showed that the cementitious activity and volume stability of the reconstructed steel slag were improved in the higher C/S or lower S/A. The cementitious activity and volume stability of the reconstructed steel slag were improved with the increase of CaF2 content. By analyzing the cementitious activity and volume stability of the reconstructed steel slag, the optimum technological parameters are obtained as follows: C/S is 2.70 , S/A is 5.78, the content of CaF2 is 4%.

Radiotherapy (RT) is one of the most widely applied treatments for cancer therapy in clinics. Herein, we constructed innovative multifunctional nanotheranostic MnO2-mSiO2@Au-HA nanoparticles (MAHNPs) based on one-pot MnO2-mSiO2 nanohybrids (MNHs) and gold nanoparticles (AuNPs) for multispectral optoacoustic tomography (MSOT)/computed tomography (CT) and magnetic resonance (MR) imaging-guided hypoxia-maneuvered radiotherapy. The MNHs were prepared via a facile one-pot approach, which avoided the leakage of MnO2 nanoparticles and increased the synthetic efficiency. The Mn2+ ions triggered the breakdown of endogenous H2O2 to generate O2 to convert the hypoxic tumor micro-environment (TME), thus enhancing radiotherapy by self-supply oxygen. In addition, hyaluronic acid (HA) was employed to modify the surface of the MnO2-mSiO2@Au nanoparticles to improve their biocompatibility and cellular uptake. The well-designed nanoparticles could perform remarkable photothermal therapy (PTT) and hypoxia-maneuvered radiotherapy (RT) simultaneously and MSOT/CT/MR imaging. The in vivo studies showed that the MAHNPs achieved almost total suppression of tumor growth without observable recurrence, which raises new possibilities for clinical nanotheranostics with multimodal diagnostic and therapeutic coalescent design.

Improving the cementitious activity and volume stability of steel slag by thermal reconstruction is an innovative method for efficient utilization of steel slag. In this study, different amounts of CaF2 and CaSO4 were added to steel slag as a mineralizer based on the determining admixtures needed for the reconstruction reaction, and the effects of CaF2 and CaSO4 on the cementitious activity and volume stability of the reconstructed steel slag were investigated. The results show that when the CaF2 content is increased to 5 wt%, the cementitious activity index of the reconstructed steel slag gradually increases to 92%, which is 12% higher than the first level technical requirement specified by the national standards, and the free CaO (f - CaO) and MgO (f-MgO) contents gradually decrease to 0.35 and 0.13 wt%, respectively. With increasing CaSO4 content, the cementitious activity index first increases and then decreases, while the contents of f -CaO and f-MgO show the opposite trend. When the CaSO4 content is 2 wt%, the activity index is 105%,which is 25%higher than the first level technical requirement specified by the national standards, and the f -CaO and f-MgO contents reach minima of 0.44 and 0.35 wt%, respectively.

Rod-shape nanoplatform have received tremendous attention owing to their enhanced ability for cell internalization and high capacity for drug loading. MoS2, widely used in electronic devices, electrocatalysis, sensor and energy-storage, has been studied as photothermal agents over the years. However, the efficacy of rod-shape MoS2 based photothermal agents for photothermal therapy has not been studied before. Here, a near-infrared (NIR) light-absorbing MoS2 nanosheets coated mesoporous silica nanorods with human serum albumin (HSA) modifying and Ce6 loading (MSNR@MoS2-HSA/Ce6) were constructed for combined photothermal and photodynamic therapy. Methods: The near-infrared (NIR) light was used to trigger the synergistic anti-tumor therapy. In addition, breast cancer cell line was applied to evaluate the in vitro anti-tumor activity. The multi-modal imaging capacity and tumor-killing efficiency of the designed nanocomposites in vivo was also demonstrated with the 4T1 tumor-bearing mouse model. Results: These nanocomposites could not only perform NIR light triggered photodynamic therapy (PDT) and photothermal therapy (PTT), but also achieve in vivo fluorescence (FL) /multispectral optical tomography (MSOT)/X-ray computed tomography (CT) triple-model bioimaging. What's more, the rod-shape nanoplatform could be endowed with better anti-tumor ability based on the EPR effect and HSA-mediated active tumor targeting. At the same time, the hyperthermia generated by MoS2 could synergistically improve the PDT effect with the acceleration of the blood flow, leading to the increase of the oxygen level in tumor tissue. Conclusion: MSNR@MoS2-HSA/Ce6 proves to be a promising multi-functional nanoplatform for effective treatment of tumor.

Snapshots of a phase transition Time-resolved x-ray scattering can be used to investigate the dynamics of materials during the switch from one structural phase to another. So far, methods provide an ensemble average and may miss crucial aspects of the detailed mechanisms at play. Wall et al. used a total-scattering technique to probe the dynamics of the ultrafast insulator-to-metal transition of vanadium dioxide (VO 2 ) (see the Perspective by Cavalleri). Femtosecond x-ray pulses provide access to the time- and momentum-resolved dynamics of the structural transition. Their results show that the photoinduced transition is of the order-disorder type, driven by an ultrafast change in the lattice potential that suddenly unlocks the vanadium atoms and yields large-amplitude uncorrelated motions, rather than occurring through a coherent displacive mechanism. Science , this issue p. 572 ; see also p. 525

The accurate and rapid quantitative detection of antibodies had a significant influence in controlling and preventing disease or toxin outbreaks. In this work, we first introduce the antibody-powered triplex-DNA nanomachine to release cargo DNA as a substitute target for sensitive electrochemiluminescence (ECL) detection of anti-digoxigenin based on a novel ternary ECL system. It is worth noting that the cargo DNA as a substitute target of antibody can further participate in an enzyme-assisted cycling strand displacement reaction to achieve ECL signal amplification and improve the sensitivity of antibody detection. Additionally, porous palladium nanospheres with a considerable catalytic activity were first applied as a coreaction accelerator to efficiently enhance the intensity of the ECL system of rubrene microblocks as luminophore and dissolved O2 as an endogenous coreactant. With the resultant ternary ECL system as a biosensing platform, a significantly enhanced initial signal was achieved in advance. Then, the ferrocene-labeled quenching probes were employed to reduce initial signal and obtain the low-background signal. Eventually, the cargo DNA made the quenching probes release and recover the signal in the presence of anti-digoxigenin. Thereupon, the wide linear range (0.01-200 nM) and low limit of detection (6.7 pM) were obtained, and this method not only reduces conjugation steps but also provides a sensitive and novel ECL analysis platform for the trace detection of other antibodies and antigen.

In order to study the effect of cement-sand ratio on the dynamic mechanical properties of the full tailings cemented backfilling, three sets of full tailings cemented backfilling specimens with different cement-sand ratios were prefabricated. The uniaxial impact of the prefabricated specimens was performed by the Ф50 mm SHPB test system. Test results showed that full tailings cemented backfilling had strong reflection and damping effects on elastic wave propagation. At lower strain rates, specimens presented strength hardening, and at higher strain rates, the test specimens presented rapid-softening strength; the strength-hardened specimen reached the peak stress at 40 μs, and the softening specimen reached the peak stress at about 18 μs; with the increase of strain rate, dynamic compressive strength, growth factor of dynamic strength, peak strain, and dynamic-static strain ratio of specimens increased totally. When the cement-sand ratio increased, ultimate dynamic compressive strength, limit dynamic strength growth factor, and ultimate peak strain of the specimen were higher; at the same strain rate, with the increase of cement content, the dynamic compressive strength, dynamic strength growth factor, and dynamic-static strain ratio of the test piece all decreased. The failure mode of the specimen was crushing failure. Under the same strain rate, when the cement content decreased, there was a higher damage degree of specimens.

Bacillus anthracis is an extremely dangerous bacterium that is associated with high morbidity and mortality. 2,6-Pyridine dicarboxylic acid (DPA) is a major biomarker of Bacillus anthracis, and it is of great significance to be able to detect DPA in a rapid, efficient, and sensitive way. Herein, a 3D network metal–organic framework (Tb-MOF) with excellent thermal and water stability was synthesized. Tb-MOF could be used to selectively detect DPA via green fluorescence recovery with a fluorescence intensity enhancement factor of 103. In addition, due to the high detection sensitivity (a detection limit of 2.4 μM) and excellent anti-interference abilities, Tb-MOF was less affected by environmental factors when compared with a “turn-off”-response luminescence sensor; it can be employed as a promising “turn-on” luminescence sensor for DPA in the future. Finally, quantum calculations showed that a large energy difference appeared between the 5D4 level of Tb3+ and the first excited triplet energy level of H2-DHBDC2−, which was the reason that the complex did not show characteristic Tb3+ emission.

In this work, we analyzed silicon (Si) ion implanted semi-insulting gallium arsenide substrates (SI-GaAs) by using a terahertz time-domain spectroscopy (THz-TDS) system. The main goal is to determine the ion doping profile via a nondestructive approach by using THz-TDS spectroscopy. This approach will bring a new appliance to replace secondary ion mass spectroscopy (SIMS). For that, we have carried out the ion implantation experiment with an implantation energy of 200 keV at different doses. Then, we analyzed the THz-TDS experimental data of implanted SI-GaAs substrates by the Drude model to achieve depth-dependent dielectric and electrical properties at THz frequencies.

With the rapid development of terahertz (THz) technology comes the need to further explore the prospects for various applications of THz systems. Due to the strong need, components and equipment involving the exploration are indispensable. In order to find the most suitable material for THz technology, we selected three common materials for different 3D printing techniques—polyamide (PA), polylactic acid (PLA), and light-curable resin. After mixing each material with a quartz powder of a different weight percentage, we observed the change in absorption coefficients and refractive indices of the mixtures by THz time-domain spectroscopy (THz-TDS). The higher the ratio of a quartz powder to a mixture was, the smaller the absorption coefficient of the mixture would be. The optimum rate of change in the absorption coefficient was attained when the weight percentage of a quartz powder in a mixture was 50 wt%. At 1 THz of the measurement of THz-TDS, the average reduction in the absorption coefficients of the three different materials mixed respectively with a 50 wt% quartz powder was 39.17%. Besides reduced absorption coefficients, the mixtures’ refractive indices also changed as the weight percentage of a quartz powder in the mixtures varied. The PLA-based sample mixed with a 50 wt% quartz powder had the highest increase in the refractive index. Mixing quartz powders with materials, therefore, is an effective method to increase refractive indices and decrease absorption coefficients. The method can be applied in 3D printing techniques in the future to enhance the efficiency of THz components manufactured with 3D printing techniques.

The dielectric constant, energy band parameters and ionicity are key physical parameters for fully understanding the dielectric properties of glasses, but their mutual interrelationship and its applicability to a wide variety of multi-component glasses have not yet been confirmed. We have applied the optical and THz spectroscopic characterization to a set of multi-component silicate oxide glasses incorporating vastly different additive components. The key physical parameters evaluated in the optical region have been interpreted consistently by the single oscillator based dielectric model. The bandgap energy (Eg) and ionicity parameter (Wemple and DiDomenico's β parameter) estimated in the optical region have shown reasonable correspondence, respectively, with the homopolar energy (Eh) and the polarization ionicity (IP) which are evaluated from the THz dielectric constant measurement. The comprehensive interrelation thus confirmed has provided simple rules between the physical parameters without limitation of glass compositions. For example, a tradeoff relation between the oscillator strength and characteristic resonance wavelength and a simple correlation between the dielectric constant and bandgap energy have been determined for the present set of multi-component glasses. The energy band parameters have been used for deriving the joint density of state diagrams, and characteristic physical/chemical nature has been identified to each glass.

Lithium-sulfur (Li-S) batteries are promising candidates for next-generation energy storage devices, while shuttle effect and Li dendrite growth severely obstruct the practical applications. Herein, well-dispersed Ni2P electrocatalysts decorated hollow carbon spheres (Ni2P-HCS) are constructed as high-efficiency bi-functional mediator for Li-S batteries. Benefiting from polar surface and high electrical conductivity, Ni2P-HCS possesses strong interaction and efficient electrocatalysis toward polysulfides. Moreover, regulated Li deposition behavior is realized on lithiated Ni2P-HCS surface ascribed to its lithiophilicity and as-formed mixed ion-electron conducting host composed of Li3P and Ni. As a result, the assembled Li-S full cells with Ni2P-HCS used as interlayer and Li host exhibit excellent rate capability (755.5 mAh g−1 at 2 C) and long-term cycling stability (capacity fading rate of 0.05% per cycle at 1 C after 500 cycles). Importantly, high areal capacity (6.67 mAh cm−2) with high sulfur loading of 5.9 mg cm−2 at low E/S ratio (6.8 μL mg−1) is achieved. The loading coefficient and catalytic effectiveness value (CEV) are proposed to evaluate catalytic efficiency of electrocatalysts. This work exploits the potential of metal phosphides in concurrently solving challenges for S cathode and Li anode, and offers insight into developing high-efficiency electrocatalysts for advanced Li-S batteries.

Litsea cubeba essential oil (LCEO), as naturally plant-derived products, possess good antimicrobial activities against many pathogens, but their high volatility and poor water solubility limit greatly the application in food industry. In this research, inclusion complex based on &beta, cyclodextrin (&beta, CD) and LCEO, was prepared by saturated aqueous solution method. An optimum condition using the response surface methodology (RSM) based on Box&ndash, Behnken design (BBD) was obtained with the inclusion time of 2 h and &beta, CD/LCEO ratio of 4.2 at 44 &deg, C. Under the condition, the greatest yield of 71.71% with entrapment efficiency of 33.60% and loading capacity of 9.07% was achieved. In addition, the structure and characteristic of LCEO/&beta, CD inclusion complex (LCEO/&beta, CD-IC) were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR), which indicated that LCEO/&beta, CD-IC was successfully formed. The particle size of LCEO/&beta, CD-IC was determined to be 17.852 &mu, m. Thermal properties of LCEO/&beta, CD-IC evaluated by thermogravimetric-differential scanning calorimetry (TG-DTA) illustrated better thermal stability of the aimed product compared with the physical mixture. Furthermore, the tests of antifungal activity showed that LCEO/&beta, CD-IC was able to control the growth of Penicillium italicum, Penicillium digitatum, and Geotrichum citri-aurantii isolated from postharvest citrus. Our present study confirmed that LCEO/&beta, CD-IC might be further applied as an alternative to chemical fungicides for protecting citrus fruit from postharvest disease.

This work reports a high wavenumber Raman analysis in human hard dental tissues, spectral differences regarding CH and OH bands between enamel and dentin, and various locations of enamel were observed and discussed.

A dual-wavelength excitation Raman probe with laser inputs at 866 nm or 1064 nm is customized and integrated into a compact Raman spectrometer that is based on an InGaAs detector. Under 1064 nm illumination, the spectrometer detects fingerprint Raman signals below 2000 cm–1. While under 866 nm illumination, the spectral range is extended to cover high-frequency region (2400–4000 cm–1) that includes major C–H and O–H Raman vibrations. We demonstrate that the dual excitation InGaAs Raman is beneficial in detecting high-frequency Raman signals, especially water contents in high-fluorescent biological samples such as human dental tissues, grape skin, and plum skin due to the suppressed fluorescence interference.

Probing single active nanoparticles of Li-ion battery electrodes is challenging but important to reveal their behaviors including morphology, mechanical properties and electrochemical reactions with an electrolyte. In this work, we in situ investigated voltage-induced behaviors of single LiNiO2 nanoparticles by merging conductive atomic force microscopy (CAFM) and amplitude modulation-frequency modulation (AM-FM) techniques. The former was used to apply a voltage between a selected single nanoparticle and a substrate through its tip, while the latter was done for imaging. Evolution in the morphology and stiffness of the nanoparticles induced by different voltages under air and dried argon atmospheres was tracked, respectively. The evolution mechanisms related to electrochemical reactions were discussed in detail. These results suggest that the merged techniques would provide an indirect and effective approach to study the behaviors and electrochemical reactions of electrode materials on the nanometer scale and even single nanoparticles.