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Molybdenum disulfide (MoS2)-based materials for piezocatalysis are unsatisfactory due to their low actual piezoelectric coefficient and poor electrical conductivity. Herein, 1T/3R phase MoS2grown in situ on multiwalled carbon nanotubes (MWCNTs) was proposed. MoS2@MWCNTs exhibited the interwoven morphology of thin nanoflowers and tubes, and the piezoelectric response of MoS2@MWCNTs was 4.07 times higher than that of MoS2via piezoresponse force microscopy (PFM) characterization. MoS2@MWCNTs exhibited superior activity with a 91% degradation rate of norfloxacin (NOR) after actually working 24 min (as for rhodamine B, reached 100% within 18 min) by pulse-mode ultrasonic vibration-triggered piezocatalysis. It was found that piezocatalysis for removing pollutants was attributed to the synergistic effect of free radicals (•OH and O2•–) and nonfree radical (1O2, key role) pathways, together with the innergenerated-H2O2promoting the degradation rate. 1O2can be generated by electron transfer and energy transfer pathways. The presence of oxygen vacancies (OVs) induced the transformation of O2to 1O2by triplet energy transfer. The fast charge transfer in MoS2@MWCNTs heterostructure and the coexistence of sulfur vacancies and OVs enhanced charge carrier separation resulting in a prominent piezoelectric effect. This work opens up new avenues for the development of efficient piezocatalysts that can be utilized for environmental purification.

Objectives: This study aimed to explore the effects of different duration and daily frequency of vestibular rehabilitation (VR) in patients with residual symptoms after benign paroxysmal positional vertigo (BPPV) successful repositioning.Method: Patients with successful BPPV repositioning (n = 118) were divided into 3 groups according to VR duration and frequency: group A (n = 30; 15 minutes, 3 times/day), group B (n = 30; 30 minutes, 3 times/day), group C (n = 28; 15 minutes, 6 times/day), and control group D (n = 30; no VR). All patients completed the dizziness handicap inventory (DHI) and vestibular rehabilitation benefit questionnaire (VRBQ) at baseline and after 2 and 4 weeks.Results: The emotional scores and the proportion of severe dizziness disability in the DHI scores were significant differences between VR groups A to C and control group D after 2 and 4 weeks (all P< .05). There were significant differences in total DHI and VRBQ scores among the VR groups A to C after 2 and 4 weeks (all P< .05). Interestingly, emotion scores were not significantly different in group A (P= .385), group B (P= .569), and group C (P= .340) between 2 and 4 weeks. Meanwhile at 2 weeks, the difference in motion-provoked dizziness score between group A and B was statistically significant (P= .02).Conclusions: A total VR duration over 4 weeks can reduce dizziness and improve VR benefits in routine therapy in patients with residual dizziness after successful BPPV repositioning. Emotional improvement can be observed after 2 weeks. VR may help to relieve motion-provoked dizziness earlier if patients are willing to consider increasing the duration to more than 15 minutes.

Nd3+doped and Er3+/Yb3+codoped NaSrGd(MoO4)3(NSGM) phosphors were synthesized and used to build an integrated temperature-feedback photothermal therapy platform. Intense green upconversion emissions were observed in Er3+/Yb3+-codoped NSGM phosphors and used to construct an all-fiber temperature sensing probe. The temperature dependent fluorescence intensity ratio (FIR) calibration curve was established and the absolute temperature sensitivity Sareached the maximum value of 0.013 K–1at 423 K. The photothermal conversion performance of NSGM:Nd3+phosphors could be easily modified by altering Nd3+doping concentration and 808 nm laser irradiation power. An integrated all-fiber photothermal temperature measurement platform was built and the temperature measurement error was smaller than ±1 K, which could simultaneously achieve photothermal conversion and temperature measurement in narrow spaces and was expected to be used in local photothermal therapy applications.

ABSTRACTFacial expressions can influence the perception of gaze direction. However, whether the sexes modulate the interaction between emotion and gaze direction remains a controversial topic. Here, we used a gaze direction judgment task and measured the cone of direct gaze (CoDG) as an index of perceived being looked at himself/herself. The results showed that participants’ sex modulated the role of emotion in gaze direction. Regarding males , the CoDG for angry faces was significantly wider than that for neutral and fearful faces, and a marginally significant difference was found in the CoDGs between fearful and neutral faces. Concerning females, the CoDG for angry and fearful faces was significantly wider than that for neutral faces, with no significant difference between fearful and angry faces. These findingssuggest that individual sex is a vital factor in modulating the interaction between gaze direction and facial expression.

Reed flower (RF)-derived porous carbon-based electrodes are produced with KOH as the activating agent and diethanolamine (DEA) as the additive via a facile method without precarbonization. DEA with good wettability can facilitate the permeation of KOH through plant tissues, thus enhancing the KOH activation and increasing the specific surface area (SSA) as well as the pore volume. In addition, DEA as a nitrogen-doping agent can also increase the nitrogen content of carbon materials. The porous carbon synthesized with DEA (RFAC-N) exhibits a significantly larger SSA of 1691 m2g–1, an evidently higher pore volume of 1.08 m3g–1, and a higher N content (1.93 wt %) than that synthesized without DEA. Examined in a symmetric two-electrode electrochemical test system with KOH as the electrolyte, RFAC-N presents a high specific capacitance (254.3 F g–1at a current density of 1 A g–1), superb rate performance (192.7 F g–1at 30 A g–1), a high energy density of 9.40 Wh kg–1, good reversibility, and excellent long cycle stability (89.5% capacity retention after 10,000 cycles at 10 A g–1). Possessing impressive properties and performance, the N-doped biomass-derived porous carbon materials with a high N content, as synthesized with a facile method presented in this work, demonstrate their vast potential in application in high-performance energy storage devices.

To investigate the heterogeneity of decidual stromal cells (DSCs) and their functional alterations during delivery, we conducted single-cell RNA sequencing analysis to characterize the transcriptomic profiles of DSCs before and after labor onset. According to their transcriptomic profiles, DSCs (6382 cells) were clustered into five subgroups with different functions. Similar to stromal cells, cells in cluster 1 were involved in cell substrate adhesion. On the other hand, cells in clusters 2 and 3 were enriched in signal transduction-related genes. Labor onset led to significant alterations in many pathways, including the activator protein 1 pathway (all clusters), as well as in the response to lipopolysaccharide (clusters 1-3). The downregulated genes were involved in coagulation, ATP synthesis, and oxygen homeostasis, possibly reflecting the oxygen and energy balance during delivery. Our findings highlight that peripartum DSCs are heterogeneous and play multiple roles in labor.

The imprinted polymers were prepared to absorb dichlorophen (DCP) by using mesoporous silica with ordered pores and high specific surface area. Both scanning electron microscopy and transmission electron microscopy results suggested that the mesoporous silica nanosphere pores had a periodic distribution. The imprinted layer of polymers was thin and uniform. The adsorption experiments showed that the adsorption of imprinted polymers was obviously improved due to the presence of mesoporous structure. The maximum adsorption capacity of MSNs@MIPs at 318 K was 91.1 mg/g, and the adsorption process rapidly reached the equilibrium within 40 min. The adsorption isotherm was well fitted by the Freundlich isotherm model, indicating that multimolecular layer adsorption mechanism governs the adsorption of DCP by the polymers. The adsorption of MSNs@MIPs complied with pseudo-second-order kinetic model. Both selective and regenerative experiments demonstrated that MSNs@MIPs can be successfully applied for selective adsorption of DCP.

Flexible sensors are of considerable interest for the development of wearable smart miniature devices. This work reported a flexible electrochemical platform based on reduced graphene oxide (rGO) for the detection of salicylic acid (SA). The free-standing and flexible rGO electrode was prepared viaa simple extruded process. Dynamic mechanical deformation and bending studies illustrated the resilience and compliance of the flexible electrode against extreme mechanical deformations. Quantitative analysis of SA was performed by using differential pulse voltammetry (DPV) with this flexible rGO electrode. Linearity ranges for SA were obtained from 1.0 × 10−10M to 1.0 × 10−5M with the detection limit of 2.3 × 10−11M (S/N = 3). This strategy provided a new insight into the design and application of flexible electrodes. It will extend the applications of rGO in sensing, bio-electronics and lab-on-chip devices.

Luminescence modification of lanthanide ions has attracted great attention due to its applications in sensing, colorful display, information transmission and anti-counterfeiting. Traditional methods of tuning fluorescence typically employ tuning compositions that are not conducive to the development of multi-environment detection and anti-counterfeiting. In this study, lanthanide ions doped ferroelectric nanocomposite was exploited with external stimuli. The upconversion luminescence modification was preformed viaboth the thermal and electric fields. The anti-thermal quenching phenomenon was observed in the prepared nano-composite, which could effectively enhance the upconversion luminescence of lanthanide ions. Based on the electromechanical softness of the ferroelectric lattice, exceptional luminescence modification was realized through electric polarization. The luminescence modifications by thermal and electric fields exhibited excellent reversibility and non-volatility. These results provide unique insights into the development of integrated stimulus responsive smart devices, colorful display and advanced multi-mode sensing materials.

Colon cancer in patients with situs inversus totalis is rarely associated with dextrocardia, and chemotherapy is commonly used for treatment. Central venous access devices are used to administer intravenous fluids and chemotherapy in patients with colon cancer. Compared with peripherally inserted central catheters and Hickman-type tunneled catheters, totally implantable vascular access devices (TIVADs) are safer and more effective. However, positioning the catheter tip may be challenging in patients with dextrocardia and situs inversus. We herein describe a novel case involving a patient with dextrocardia and colon cancer who was treated by TIVAD insertion with intracavitary electrocardiography-aided tip localization.

Anastrozole is currently used as first‐line treatment in locally advanced or metastatic breast cancer. A generic anastrozole tablet was developed to offer an alternative to the marketed tablet formulation. The aim of the current study was to evaluate the bioequivalence between the test and reference formulations of anastrozole in a single‐dose, 2‐period, 2‐sequence crossover study with a 14‐day washout interval. A total of 20 healthy male Chinese volunteers were enrolled and completed the study, after oral administration of a single dose of 1.0‐mg test and reference formulations of anastrozole. The blood samples were collected at different times and were determined by a fully validated high‐pressure liquid chromatography–tandem mass spectrometry method. The evaluated pharmacokinetic parameters, including Cmax, AUC0–t, and AUC0–∞, were assessed for bioequivalence based on current guidelines. The observed pharmacokinetic parameters of anastrozole of the test drug were similar to those of the reference formulation. The 90% confidence intervals of test/reference ratios for Cmax, AUC0−t, and AUC0−∞were within the bioequivalence acceptance range of 80%–125%. The results obtained from these healthy Chinese subjects in this study suggest that the test formulation of anastrozole 1.0‐mg tablet is bioequivalent to the reference formulation (Arimidex 1.0‐mg tablet).

The hydroxyl radical (OH) is one of the most important oxidizing species in air whose concentration indicates the air quality. In this work, an indirect method was developed to determine OH based on the electrochemical signal of 2,5-dihydroxybenzoic acid (2,5-DHBA), a specific reaction product of salicylic acid and OH. The molecular imprinting technique was introduced into this work to improve the selectivity and sensitivity of this method. 2,5-DHBA was imprinted on reduced graphene oxide (rGO) viaa simple electrochemical method by using pyrrole as the functional monomer. rGO not only provides abundant active sites for 2,5-DHBA imprinting but also improves the conductivity and mass transportation and increases the accessibility of active sites for 2,5-DHBA recognition. The differential pulse voltammetry (DPV) signals of 2,5-DHBA were used to evaluate the performance of the molecularly imprinted polymer (MIP) based sensor. The linear range for the concentration of 2,5-DHBA was from 5.0 × 10−8to 4.5 × 10−5M and the detection limit was down to 2.74 × 10−9M. A linearity for OH concentration ranging from 8.4 × 106to 7.5 × 109molecules per cm3was obtained. The low detection limit for OH was down to 4.6 × 105molecules per cm3when using this sensor. The atmospheric OH concentration in Yangzhou has been successfully detected by this method. This work extended the molecularly imprinted polymers to the indirect detection of OH in the atmosphere with a simplified sample collection and detection process and good sensitivity.

In this paper, we utilized an integrated electrochemical probe which consist of two redox groups instead of two redox molecules, the integrated probe simultaneously provided referenced signal and target responded signal. Combining with merits of enlarging the electroactive surface area and promoting the electron transfer of carbon nanohorns modified electrode, a new ratiometric electrochemical sensor for the assay of a-glucosidase and its inhibitors was fabricated. The ratiometric signal enabled the detection of a-glucosidase in a range of 0.001-0.016 U/mL with a detection limit of 0.00056 U/mL, which is lower than most of the existing methods. Furthermore, two a-glucosidase inhibitors, acarbose and mulberry bark, were used to assess the feasibility of screening potential anti-diabetic medicine, and the IC50 values of 0.55 mM and 3.38 mg/mL were obtained respectively. Thus, our proposed sensing strategy broadens the way for the design of novel ratiometric electrochemical sensors, and greatly extended the application of electrochemistry in medical analysis.

Acute liver failure (ALF) is a severe liver disease caused by many reasons. One of them is the overdosed acetaminophen (APAP), which is metabolized into N‐acetyl‐p‐benzoquinone imine (NAPQI), an excessive toxic metabolite, by CYP2E1, resulting in excessive reactive oxygen species (ROS), exhausted glutathione (GSH), and thereafter hepatocyte necrosis. N‐acetylcysteine is the Food and Drug Administration‐approved drug for detoxification of APAP, but it has limited clinical application due to the short therapeutic time window and concentration‐related adverse effects. In this study, a carrier‐free and bilirubin dotted nanoparticle (B/BG@N) is developed, which is formed using bilirubin and 18β‐Glycyrrhetinic acid, and bovine serum albumin (BSA) is then adsorbed to mimic the in vivo behavior of the conjugated bilirubin for hitchhiking. The results demonstrate that B/BG@N can effectively reduce the production of NAPQI as well as exhibit antioxidant effects against intracellular oxidative stress via regulating the nuclear factor erythroid 2‐related factor 2/heme oxygenase‐1 signal axis and reducing the production of inflammatory factors. In vivo study shows that B/BG@N can effectively improve the clinical symptom of the mice model. This study suggests that B/BG@N own increases circulation half‐life, improves accumulation in the liver, and dual detoxification, providing a promising strategy for clinical ALF treatment. Carrier‐free, bilirubin‐dotted, and albumin‐bound 18β‐glycyrrhetinic acid nanoparticles (B/BG@N) are developed to mimic the in vivo behavior of the conjugated bilirubin in the body for liver‐targeted delivery as well as exert dual detoxification by scavenging reactive oxygen species and inhibiting CYP2E1 for acute liver failure therapy.

In this work, the magnetic Fe3O4imprinted polymers were prepared with the precipitation polymerization method. The polymers were used to selectively identify dichlorophen in complex environmental system. The scanning electron microscopy and transmission electron microscopy scans of magnetic Fe3O4molecularly imprinted polymers (MMIPs) were carried out. The adsorption properties of MMIPs were examined by adsorption isotherms, kinetics, and selectivity experiments. The Langmuir adsorption isotherm well fitted the adsorption experimental data, and an increase of temperature enhanced the adsorption capacity. The equilibrium adsorption capacity of MMIPs at 318 K was 50.45 mg g–1. The data of kinetics experiments were well fitted by pseudo-second-order equation. Compared to nonimprinted polymer, the MMIPs had more specific selectivity and higher adsorption performance for chlorophene with similar structure. In addition, the regeneration experiments demonstrated that MMIPs have stable adsorption capacity for target molecules and can be quickly recovered in applied magnetic field. Therefore, our study provided an appropriate imprinted polymer material for the adsorption of dichlorophen in water.

It is well known that the activity and stability of electrocatalysts are largely dependent on their surface facets. In this work, we have successfully regulated surface facets of three-dimensional (3D) metallic Aum-naerogels by salt-induced assembly of citrate-stabilized gold nanoparticles (Au NPs) of two different sizes and further size-dependent localized Ostwald ripening at controlled particle number ratios, where mand nrepresent the size of Au NPs. In addition, 3D Aum-n–Pd aerogels were further synthesized on the basis of Aum-naerogels and also bear controlled surface facets because of the formation of ultrathin Pd layers on Aum-naerogels. Taking the electrooxidation of small organic molecules (such as methanol and ethanol) by the resulting Aum-nand Aum-n–Pd aerogels as examples, it is found that surface facets of metallic aerogels with excellent performance can be regulated to realize preferential surface facets for methanol oxidation and ethanol oxidation, respectively. Moreover, they also indeed simultaneously bear high activity and excellent stability. Furthermore, their activities and stability are also highly dependent on the area ratio of active facets and inactive facets on their surfaces, respectively, and these ratios are varied via the mismatch of sizes of adjacent NPs. Thus, this work not only demonstrates the realization of the regulation of the surface facets of metallic aerogels by size-dependent localized Ostwald ripening but also will open up a new way to improve electrocatalytic performance of 3D metallic aerogels by surface regulation.

(Y0.87La0.1Zr0.03)2O3nanopowders doped with various concentrations of Tm3+and Ho3+were prepared by the citrate method. The standard cubic Y2O3phase can be matched in the Tm3+/Ho3+co-doped (Y0.87La0.1Zr0.03)2O3nanopowders. The nanopowders exhibit average particle sizes of 40, 60, 80 and 100 nm after calcinated at 900, 1000, 1100 and 1200 °C, respectively. The energy transfer from Tm3+to Ho3+and the optimum fluorescence emission around 2 μm were investigated. Results indicate that the emission bands at around 1.86 and 1.95 μm correspond to 3F4→3H6transition of Tm3+and 5I7→5I8transition of Ho3+, respectively. Better spectral properties were achieved in Tm3+/Ho3+co-doped (Y0.87La0.1Zr0.03)2O3nanopowders with the average size of 100 nm obtained at the conditions of the treatment of precursors calcinated at 1200 °C for 2 h doped with 1.5 mol% Tm3+and 1 mol% Ho3+.

Tb3+-doped high density borogermanate glasses were prepared by melt-quenching method. Their physical and luminescent properties including differential thermal analysis (DTA), density, transmittance spectra, photoluminescence, and X-ray excited luminescence spectra were investigated. The densities of the glasses doped with Tb3+were in the range from 5.690 to 6.086 g/cm3. Under UV and X-ray excitations, the glasses showed intense green emissions. The lifetimes of Tb3+doped borogermanate glasses were in the range from 1.597 to 1.869 ms. The results indicated that Tb3+doped borogermanate glasses could be scintillator candidate used in X-ray detection application.

Here we report the evaluation of the frequency of subjective and objective otolaryngologic findings and therapeutic results in 32 patients with mitochondrial encephalomyopathy (MEM) from September 2001 to June 2021. Our analysis included studying the patients’ family histories, the clinical manifestations of MEM, and the therapeutic effects of treatments. The patients’ ages ranged from 2 to 77 years, with a median age of 12.3 years. We found that MEM ENT symptoms were characterized by hearing loss, dysphagia, and facial weakness. Most cases of sensorineural hearing loss were bilateral symmetrical progressive or sudden deafness since adolescence, which were often underestimated. Associated neuromuscular symptoms required mtDNA testing. Dysphagia and facial weakness occurred preferentially in middle-aged patients, and muscle biopsies were advised. Distortion product otoacoustic emissions and auditory brainstem responsetesting were more sensitive and reliable than pure tone averages for objective monitoring of pathogenesis. Administration of the mitochondrial synthase complex benefited patients with acute episodes. If patients did not fully recover and exhibitedresidual language deficits, hearing aids or cochlear implants were recommended. Counsel was given regarding synthetical treatments for facial weakness, endoscopic circopharyngealmyotomy for dysphagia, and surgical correction of ptosis. This study demonstrates that increased awareness of these symptoms is important to address appropriate interventions and avoid complications such as ablepsia, aphasia, social isolation, malnutrition, aspiration pneumonia, and heart failure in the setting of MEM.

Clay-based composite materials have been widely used for environmental remediation due to their excellent physicochemical properties, however, there are few studies on clay-based composite materials as ozone catalyst carriers. In this study, Ce-loaded sepiolite (Ce/SEP) catalyst was synthesized using an impregnation-calcination method. Ce/SEP catalysts had a higher efficiency for heterogeneous catalytic ozonation than sepiolite alone. Among different mass ratios of Ce element to sepiolite (5 % Ce/SEP, 7 % Ce/SEP, 10 % Ce/SEP, and 15 % Ce/SEP), 10 % Ce/SEP showed the best catalytic performance with the mineralization efficiency of p-nitrophenol (PNP) as 71 % that was 1.15, 1.08, and 1.18 times higher than that of 5 % Ce/SEP, 7 % Ce/SEP, and 15 % Ce/SEP, and increased by 30 % compared to that of the ozonation alone. Larger surface area and abundance of strong acid sites of Ce/SEP favored adsorption of ozone molecules on the catalyst surface. High content of oxygen vacancies in the catalyst promoted Ce3+/Ce4+cycling and subsequently a superior catalytic activity of the Ce/SEP catalyst. In addition, free radical quenching experiments as well as electron spin resonance analysis indicated that hydroxyl radical (∙OH) was the main contributor to the mineralization of PNP in this system. This study provides a novel strategy for the heterogeneous catalytic ozonation of refractory organic pollutants in water.

Sodium thiosulfate–modified activated carbon (TDAC-ST) was prepared from Thalia dealbata, and its ability to remove streptomycin (STM) from aqueous solutions was examined. The surface properties of TDAC-ST and the original carbon (TDAC) were also measured by scanning electron microscopy, N2adsorption/desorption isotherms, Fourier transform infrared spectroscopy, and energy dispersive spectroscopy. The results indicated that modification with sodium thiosulfate slightly decreased the carbon’s surface area but introduced more functional groups and improved the adsorption ability greatly as compared to the original carbon. The effects of solution pH, initial STM concentration and contact time on adsorption system were also studied. The kinetics data followed the pseudo-second-order kinetics model, and the adsorption isotherms fit the Langmuir isotherm equation quite well, and the maximum adsorption capacity of was 247.65 and 170.84 mg/g for TDAC-ST and TDAC, respectively. The results indicated that sodium thiosulfate modification could greatly enhance the adsorption of STM onto activated carbon, and TDAC-ST was a promising adsorbent for the removal of streptomycin from aqueous solutions.

Measurement of carcinogenic Cr(VI) in ambient PM is challenging due to potential errors associated with conversion between Cr(VI) (a carcinogen) and Cr(III) (an essential nutrient). Cr(III) conversion is a particular concern due to its >80% atomic abundance in total Cr. U.S. Environmental Protection Agency (EPA) method 6800 that uses water-soluble isotope spikes can be used to correct the interconversion. However, whether the enriched Cr(III) isotope spikes can adequately mimic the Cr(III) species originally in ambient PM is unknown. This study examined the water solubility of Cr(III) in ambient PM and discussed its influence on Cr(VI) measurement. Ambient PM10samples were collected on Teflon filters at four sites in New Jersey that may have different Cr emission sources. The samples were ultrasonically extracted with 5 mL DI-H2O (pH 5.7) at room temperature for 40 min, and then analyzed by ion chromatography–inductively coupled plasma mass spectrometry (IC-ICPMS). Cr(III) was below detection limit (0.06 ng/m3) for all samples, suggesting water-soluble Cr(III) species, such as CrCl3, Cr(NO3)3, and amorphous Cr(OH)3, in the ambient PM were negligible. Therefore, the enriched 50Cr(III) isotope spike (in the form of Cr(NO3)3) could not mimic the original ambient Cr(III). Only the conversion of 53Cr(VI) (in the form of K2CrO4) was taken into account when correcting the interconversion. We then used NaHCO3-pretreated MCE filters (prespiked with enriched isotope species) to measure Cr(VI) in the ambient PM10. The samples were ultrasonically extracted at 60 C pH 9 solutions for 40 min followed by IC-ICPMS analysis. Due to the correction of Cr(VI) reduction, the Cr(VI) concentrations determined by EPA method 6800, 0.26 ± 0.16 (summer) and 0.16 ± 0.11(winter) ng/m3(n = 64), were significantly greater than those by the external standard curve, 0.21 ± 0.17 (summer) and 0.10 ± 0.07 (winter) ng/m3(n = 56) (p < 0.01, Student’s t-test). Our study revealed that appropriate application of EPA method 6800 is important because it only applies to soluble fraction of Cr species in ambient PM.ImplicationsAccurate measurement of carcinogenic Cr(VI) in ambient PM is challenging due to conversion between Cr(VI) (a human carcinogen) and Cr(III) (a human essential nutrient). The conversion of Cr(III) is of particular concern due to its dominant presence in total Cr (>80%). This study examined the water solubility of Cr(III) in ambient PM that was collected at four locations in New Jersey. Then we discussed the influence of Cr(III) solubility on the application of EPA method 6800, which utilizes enriched isotope spikes to correct the interconversion. Our results suggested that appropriate application of EPA method 6800 is important because it only applies to soluble fraction of Cr species.

AbstractAdsorption of tetracycline (TC) and ciprofloxacin (CPX) onto activated carbon prepared from lignin by H3PO4impregnated was investigated. Lignin-activated carbon (LGAC) was carbonized at 450°C in a muffle furnace for 1 h. Scanning electron microscope, N2adsorption–desorption isotherms, X-ray diffraction, pH at the point of zero charge and Boehm titration analysis need to characterize the properties of LGAC. Batched adsorption experiments were performed to study the adsorption properties and interaction mechanisms between TC/CPX and LGAC. The prepared activated carbon was found to have a porous structure with surface area of 931.53 m2/g and many functional groups (acidic groups, basic groups). The adsorption kinetics for the two adsorbates both well fitted the pseudo-second-order model (R2 > 0.99). Compared with Temkin isotherm and Freundlich isotherm, the adsorption equilibrium data were very well represented by the Langmuir isotherm. The maximum adsorption capacities for the TC and CPX calculated by the Langmuir isotherm model were high at 475.48 and 418.60 mg/g, respectively. Thermodynamics study showed that the adsorption was spontaneous and favorable. These results suggested that LGAC could be an effective adsorbent for removal of TC and CPX.

AbstractLeather activated carbon (LAC) was prepared from the leather waste by H3PO4impregnated at 105°C for 3 h and activated at 450°C for 1 h in a muffle furnace. Based on LAC, Mn-modified leather activated carbon (LAC-Mn) was also studied. The two adsorbents were characterized by scanning electron microscopy, pore distribution, N2adsorption/desorption isotherms, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Several factors, such as contact time, dosage, and pH were studied, which indicated that cation exchange, hydrophobicity, and π-electron-donor–acceptor interaction were likely the adsorption mechanisms for basic fuchsin adsorption. Meanwhile, adsorbent effects of LAC and LAC-Mn were highly pH dependent, which reached maximum under alkaline conditions. The adsorption kinetic followed the pseudo-second-order kinetic model with high correlation coefficients (R2 > 0.99), which means intra-particle diffusion process was not the only mechanism involved. Thermodynamics showed that the Langmuir isotherm equation can describe adsorption isotherms, and the maximum adsorption capacity of activated carbon increased from 139.28 to 182.48 mg/g after being modified by Mn(II). The adsorption process was a spontaneous and endothermic process.

Ce3+, Tb3+ singly-doped and co-doped Ca2LiSiO4F phosphors have been synthesized through conventional solid-state reaction. Their luminescence properties are studied. Under UV excitation, Ce3+ singly-doped Ca2LiSiO4F phosphor emit blue light (460 nm), while Tb3+ singly-doped phosphor presents yellowish green color with emission peaks at 414, 437, 486, 543, 588, and 620 nm. The excitation spectra of Ce3+ and Tb3+ co-doped Ca2LiSiO4F monitored at 543 nm show a strong broad excitation band in the UV region with a maximum at 362 nm. Excited at 370 nm, Ce3+ and Tb3+ co-doped Ca2LiSiO4F phosphor presents bluish white color with the emission peaks at 460, 486, 543, 588, and 620 nm. The energy transfer from Ce3+ to Tb3+ occurs in the co-doped Ca2LiSiO4F phosphors and is a resonance-type energy transfer due to the spectral overlap between the 460 nm emission of Ce3+ and the excitation spectra monitored at 543 nm of Tb3+. The decay curves of 460 emission from Ce3+ in the co-doped phosphors and the calculated lifetime results confirm the energy transfer. The results indicate that these phosphors have potential as phosphor candidates used for white LEDs pumped by UV chips.

The B2O3-doped MgTiO3 powders and ceramics have been prepared by sol-gel method using Mg(NO3)26H2O, Ti(C4H9O)4 and H3BO3 as the starting materials. The sintering behavior and microwave dielectric properties of ceramics prepared from powders with different particle sizes were investigated. The gels were calcined at 650, 700, 750, 800, 850 and 900 °C and the derived particle sizes of powders were 20–30 nm, 30–40 nm, 40–60 nm, 60–90 nm, 90–120 nm and 120–150 nm, respectively The nanoparticles with the size of 30–60 nm benefited the sintering process with high surface energy whereas nanoparticles with the size of 20–30 nm damaged the microwave dielectric properties due to the pores in the ceramics. The addition of B2O3 used as a liquid sintering aid reduced the sintering temperature of MgTiO3 ceramic, which was supposed to enter the MgTiO3 lattice and resulted in the formation of (MgTi)2(BO3)O phase. The B2O3-doped MgTiO3 ceramic sintered at 1100°C and prepared from the nanoparticles of 40–60 nm had compact structure and exhibited good microwave dielectric properties: ɛr=17.63, Q × f=33,768 GHz τf=−48×10−6 °C−1. [ABSTRACT FROM AUTHOR]

AbstractThis paper reports a study of adsorption of Cd(II) from aqueous solutions using activated carbon made from lotus stalks (LSAC). The properties of LSAC were characterized by scanning electron microscopy and BET surface area. Zeta potential was also determined. The batch Cd(II) adsorption on LSAC was performed to study the different sorption parameters (time, pH, temperature and ionic strength) that influence the adsorption of Cd(II) onto LSAC and to explore the adsorption mechanisms. Bench-scale column tests were also carried out to determine breakthrough curves with varying flow rates and fixed-bed heights. In general, the theoretical qecalculated using the pseudo-second-order kinetic model agreed better with the experimental data than the first-order one. Among the three widely-used isotherms (Langmuir, Freundlich, and Temkin models), the Langmuir model appeared to describe the experimental results best. The Adam–Bohart equation was appropriate for relative concentration ranging from 0.01 up to 0.5 in this study. The pH of the initial solution affected the sorption of Cd(II) on LSAC to the greatest extent, and presence of Mg2+resulted in a larger competition to the active sites than Na+, implying ion exchange and electrostatic attraction adsorption mechanisms.

Green- and yellow-emitting α- and β-Zn2SiO4:Mn2+nanocrystals incorporated into glass ceramics have been selectively synthesized successfully by a conventional melt-quenching method. XRD, EPR, TEM, EDS, and electronic optical spectroscopy were employed to discriminate the formation of α- and β-Zn2SiO4:Mn2+nanocrystals and further to elucidate the coordination environment of Mn2+in the yellow-emitting Zn2SiO4:Mn2+practical material. The combination of crystal field calculation with the experimental absorption and excitation spectra enables us to interpret optical spectroscopic features and therefore correlate the optical spectroscopy to the corresponding crystal structure. This work exemplified the correlation between the optical spectroscopy and coordination around the Mn2+ion and also shed light on the application of glass ceramics containing α- and β-Zn2SiO4:Mn2+nanocrystals for UV and blue chip excited white LEDs.

Cr^4+-doped transparent β-Zn_2SiO_4 glass-ceramics were prepared by heat treatment on the as-made glasses. It was confirmed from the absorption spectra that Cr^4+-doped β-Zn_2SiO_4 glass-ceramics are indeed a low-field system. The broadband infrared emission centering at 1342 nm with the full width at half-maximum of more than 285 nm was observed by exciting the glass-ceramics with the excitation of an 808 nm laser diode. The observed infrared emission could be attributed to Cr^4+ ions at low-field sites in β-Zn_2SiO_4 glass-ceramics.

Interferometric optical testing using computer-generated hologram (CGH) can give highly accurate measurement of aspheric surfaces has been proved. After the system is designed, a phase function is obtained according to the CGH's surface plane. For the requirement of accuracy, an optimization algorithm that transfers the phase function into a certain mask pattern file is presented in this letter, based on the relationship between the pattern error of CGH and the output wavefront accuracy. Then the writing machine is able to fabricate such a mask with this kind of file. With that mask, an improved procedure on fabrication of phase type CGH is also presented. Interferometric test results of an aspheric surface show that the whole test system obtains the demanded accuracy.

AbstractObjective: It was the aim of this study to explore the use of auditory steady-state response (ASSR) to multiple simultaneous stimuli for threshold estimation in young children. Method: The subjects consisted of 40 children, aged from 6 months to 5 years, with variant degrees of sensorineural hearing loss. Simultaneous tonepips (0.5, 1, 2 and 4 kHz) with an amplitude modulated at different rates from 77 to 103 Hz were presented to both ears by insert phones. All children were tested with ASSR and age-appropriate behavioral tests. Results: We found that (1) ASSR thresholds were usually higher than behavioral thresholds with a difference of 8–15 dB, (2) the behavioral thresholds were significantly correlated with ASSR thresholds (p = 0.000), and (3) there was a great difference between ASSR thresholds and behavioral thresholds found in a child with auditory neuropathy. Conclusion: Being objective, frequency specific and well correlated with behavioral thresholds, ASSR to multiple simultaneous stimuli was proven to be a good tool to predict behavioral hearing thresholds.Copyright © 2006 S. Karger AG, Basel

We report gain measurements in Tm^3+?Yb^3+-codoped tellurite glass fibers in the 1460–1530-nm region using a conventional 980-nm pumping scheme. The gain spectrum is dependent on the geometry of the fiber and the length owing to the superfluorescence upconversion pump scheme.

In this paper, we utilized an integrated electrochemical probe which consist of two redox groups instead of two redox molecules, the integrated probe simultaneously provided referenced signal and target responded signal. Combining with merits of enlarging the electroactive surface area and promoting the electron transfer of carbon nanohorns modified electrode, a new ratiometric electrochemical sensor for the assay of α-glucosidase and its inhibitors was fabricated. The ratiometric signal enabled the detection of α-glucosidase in a range of 0.001–0.016 U/mL with a detection limit of 0.00056 U/mL, which is lower than most of the existing methods. Furthermore, two α-glucosidase inhibitors, acarbose and mulberry bark, were used to assess the feasibility of screening potential anti-diabetic medicine, and the IC50values of 0.55 mM and 3.38 mg/mL were obtained respectively. Thus, our proposed sensing strategy broadens the way for the design of novel ratiometric electrochemical sensors, and greatly extended the application of electrochemistry in medical analysis.

Infrared-to-visible upconverted luminescent spectra of Er^3+ and La^3+ codoped Y_2O_3 powders are investigated. By introducing La^3+ ions, the upconversion green radiation is found to be greatly enhanced when compared with the powders with La^3+ absent. Such enhancement can be attributed to the modification of the local symmetry surrounding the Er^3+ ion, which benefits the intra-4f transitions of Er^3+ ion, and the decreasing interaction between Er^3+ ions, which suppresses the energy transfer process F_7/24+I4_11/2?F4_9/2+F4_9/2.

Based on the data analysis of economic development and the water environmental quality from 2002 to 2012 in the Nansi Lake Basin in China, the correlation between economic development and the water environmental quality was researched. Analysis shows that the GDP of the Nansi Lake Basin had an average annual growth of 7.3% in 2012, and the COD and CODMn had the average annual decrease of 7.69% and 6.79%, respectively, compared to 2002. Basin water environmental quality overall improved, reaching Class III of the “Environmental quality standards for surface water (GB3838-2002).” The pollution of the water environment was analyzed from three aspects: agricultural fertilizers and pesticides, livestock, and aquaculture. Results indicated that the water pollution of the Nansi Lake Basin mainly came from nonpoint source pollution, accounting for more than 80% of the overall pollution. The contributions of both agricultural fertilizers and pesticides account for more than 85% of the overall nonpoint source, followed by livestock and aquaculture. According to the water pollution characteristics of the Nansi Lake Basin, the basin pollution treatment strategy and prevention and treatment system were dissected, to solve the pollution problem of the Nansi Lake Basin.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.