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The growing concerns over the environmental toxicity of sulfonamides (SNs) require immediate action to establish efficient and sustainable processes to address this issue. Adsorption, photodegradation and Fenton/Fenton-like reactions are the most applied processes to remove SNs. However, the adsorption behavior, degradation mechanisms and toxicity of intermediates need further investigation to guide engineering applications. The review focuses on the recent progress and challenges on adsorption, photodegradation and Fenton/Fenton-like techniques for SNs removal. In addition, influences of solution pH and matrix components on adsorption mechanisms are discussed. In particular, the degradation pathway of SNs and toxicity assessment of their intermediates are also analyzed. Finally, conclusions and research gaps in this field are briefly proposed. Publications on this topic have grown exponentially over the last decade. This review provides a unique and comprehensive environmental perspective, as well as the latest knowledge on SNs adsorption and reactive removal by different technologies.

Pristine biochar, a low-cost, sustainable and environmentally friendly material, has been regarded as an effective potentially toxic elements scavenger for many years. However, with the development of urbanization and industrialization, more types and quantities of potentially toxic elements are discharged into the environment indiscriminately, which has already exceeded the limit of pristine biochar as potentially toxic elements scavenger. Therefore, designed biochar with higher surface area, more functional groups, and higher potentially toxic elements scavenging efficiency has been concerned by researchers. Herein, the review begins with the fundamental aspects of pristine biochar fabrication, including pyrolysis, hydrothermal carbonization and some other strategies. Then the synthetic methods of designed biochar were presented to develop to control the surface morphology, functional groups and some other phy-chemical properties based on some physical and chemical design, which were more beneficial for potentially toxic elements scavenging compared with pristine biochar. Most importantly, the latest advances in biochar materials for typical contaminated potentially toxic elements (lead, cadmium, chromium, arsenic, mercury, copper, and zinc) in aquatic environments have been specifically and comprehensively performed to deeply investigate their involved mechanisms. Finally, future directions and potential challenges for this emerging frontier are discussed. It is believed that this review can afford powerful influences on the development of biochar technologies for potentially toxic elements scavenging in both experiment research and large-scale practical applications.

Anaerobic digestion is widely identified as a sustainable technology for the treatment of waste activated sludge (WAS). However, various antibiotics enriched in WAS making the anaerobic digestion process full of uncertainty. This experiment studied the potential impact of a shock load of macrolide antibiotic clarithromycin (CLA) on CH4 production from anaerobic digestion of thermal pretreatments (55 °C, 10 h) WAS. Experimental results showed that the CH4 production rate was significantly suppressed in the existence of CLA during the first 10 days of anaerobic digestion, but gradually recovered thereafter. Although the total cumulative CH4 yield in the presence or absence of CLA showed little difference after 36 days of digestion, the maximal CH4 production rate decreased from 22.3 ± 0.7 mL/(g volatile suspended solids (VSS)·d) to 15.0 ± 0.4 mL/(g VSS·d) with CLA concentration elevated from 0 to 2000 mg/kg total suspended solids. Mechanism investigations showed that CLA had negative effect on the process of hydrolysis, acidogenesis, acetogenesis, homo-acetogenesis and methanogenesis, but its longer-time and more-severely inhibitory effect on acetogenesis and methanogenesis than other process was the main reason for the lower CH4 production rate in the CLA-added reactors. IonS5TMXL sequencing analysis showed that the relative abundance of typical syntrophic acetogens, such as Syntrophomonas and Syntrophorhabdus, and the methanogens, such as Methanosaeta and the hydrogenotrophic methanogens all increased with the addition of CLA at the later period of digestion. Their changes were consisted with the variations of volatile fatty acids and CH4 in digesters.

Cadmium (Cd) contamination in river sediments becomes increasingly serious, and phytoremediation has been used to remediate Cd contaminated sediments, but the remediation efficiency needs to be improved. In this study, tea waste derived biochar (TB) was used to facilitate the phytoremediation of Cd contaminated sediments. Results showed that TB at 100, 500 and 1000 mg kg−1 increased Cd accumulation and translocation in ramie seedlings by changing Cd speciation in sediments and altering the subcellular distribution of Cd in plant cells. TB at low contents alleviated Cd induced toxicity in ramie seedlings by promoting plant growth and mitigating the oxidative stress. In addition, the activities of urease-, phosphatase-, and catalase-producing microbes in the Cd contaminated sediments were promoted by the application of TB. These findings demonstrated that biochar at low concentrations could improve the phytoremediation efficiency and mitigating Cd-induced toxicity to plants and microbes in Cd contaminated sediments. This study herein provides a novel technological application of waste biomass in controlling and mitigating risks of heavy metals.

Suspended sediments are important contributors to the material exchanges between the sea surface and bottom and between the coastal waters and shelf seas. The East China Sea (ECS), connecting the Chinese continent and the western Pacific, receives a large amount of Yangtze River-delivered sediments. However, due to the climate change and intense human activities in recent years, the amount of Yangtze River-delivered sediment decreased by two thirds. Fewer work has been conducted on the accompanying changes of suspended sediment concentration (SSC) over the inner shelf of the ECS. Thus, in this study, based on the long-term water temperature, salinity, and SSC data derived from MODIS during 2003–2018, the spatiotemporal variations of SSC and the effects from oceanic fronts were studied. The results indicated a typical seasonal change of the SSC with the effect of a thermocline in summer and thermal-saline front in winter, respectively. Regarding the long-term variation of the SSC from 2003 to 2018, it displayed significant differences in spatial distribution. The SSC anomaly exhibited the opposite phases between the north and south parts of 28–29°N and between the landside and seaside of the front at the isobaths of 20 m–40 m along the Zhe-Min Coast. In general, wind is the controlling factor that affects the SSC in most area of the Zhe-Min coast, especially in spring and winter seasons.

In this study, the bamboo biomass loaded with ethylenediaminetetraacetic acid (EDTA) intercalated Mg/Al-layered double hydroxides (LDH) was calcined to obtain a novel nano-adsorbent (BC@EDTA-LDH), and BC@EDTA-LDH was used to remove hexavalent chromium (Cr(VI)) in aqueous solutions. The results showed that the interaction between LDH and Cr(VI) on biochar played a dominant part in adsorption. The LDH of Cr(VI) intercalation was successfully reconstructed after adsorption. Fourier transform infrared spectra and X-ray diffraction results confirmed the reconstruction of Mg/Al-LDH. LDH had sustained release effect on the solution. As the pH values increased, the electrostatic repulsion between Cr2O72− and OH– increased, and there existed competition for adsorption sites. The maximum adsorption capacity of Cr(VI) was 38 mg/g. The data was well-fitted with pseudo second-order model and Langmuir-Freundlich model. BC@EDTA-LDH showed a high adsorption capacity and was potentially suitable for removing heavy metals in wastewater.

Understanding of how anaerobic digestion (AD)-related microbiomes are constructed by operational parameters or their interactions within the biochemical process is limited. Using high-throughput sequencing and molecular ecological network analysis, this study shows the succession of AD-related microbiome hosting diverse members of the phylum Actinobacteria, Bacteroidetes, Euryarchaeota, and Firmicutes, which were affected by organic loading rate (OLR) and hydraulic retention time (HRT). OLR formed finer microbial network modules than HRT (12 vs. 6), suggesting the further subdivision of functional components. Biomarkers were also identified in OLR or HRT groups (e.g. the family Actinomycetaceae, Methanosaetaceae and Aminiphilaceae). The most pair-wise link between Firmicutes and biogas production indicates the keystone members based on network features can be considered as markers in the regulation of AD. A set of 40% species (“core microbiome”) were similar across different digesters. Such noteworthy overlap of microbiomes indicates they are generalists in maintaining the ecological stability of digesters.

MaiLuoNing injection is a traditional Chinese medicine that used clinically since the 1950s in China. However, anaphylactic reactions, through the potentiation of mast cell degranulation, have been reported. In the present study, a rat basophilic leukemia-2H3 cell membrane chromatography coupled with high-performance liquid chromatography and electrospray ionization-ion trap-time of flight-mass spectrometry method was established for screening, analyzing, and identifying the potential anaphylactic components of MaiLuoNing injection. Harpagoside, a potential degranulator of rat basophilic leukemia-2H3 cells, was retained in rat basophilic leukemia-2H3 cell membrane chromatography. We aimed to evaluate the retained components to determine which of those were capable of inducing degranulation of basophilic leukemia cells. A β-hexosaminidase assay revealed that harpagoside can induce rat basophilic leukemia-2H3 cell degranulation in a dose-dependent manner. BLBA/c mice also exhibit passive cutaneous anaphylaxis in response to harpagoside. These results indicate that rat basophilic leukemia-2H3 cell membrane chromatography coupled with high-performance liquid chromatography and electrospray ionization ion trap time-of-flight mass spectrometry is effective in screening for the anaphylactic components of MaiLuoNing injection.

The Federal Highway Administration conducted controlled loading tests on the US Route 23 Test Road under hot weather conditions in 1998. The testing was conducted using three tyre inflation pressures (TIPs) for four tyre types in two configurations on two asphalt concrete pavement sections. The pavement response data were collected from strain rosette sensors glued to the existing surface pavement layer and were adjusted to common temperature, lateral offset distance and speed for comparison purposes. The comparisons of the adjusted strain responses revealed the impact of the TIP on pavement strain responses and distress prediction. Mechanistic-Empirical Pavement Design Guide fatigue cracking and rutting models were used to predict the damage influenced by TIPs to the experimental pavement sections. The most road-friendly inflation pressure is recommended for each tyre configuration based on the resulting pavement service life, with pavement thickness influencing distress predictions. The two pavement sec...

The Virginia Polytechnic Institute and State University is developing an integrated transportation monitoring system that will be capable of monitoring pavement and traffic simultaneously. As part of the system, a backcalculation method, which is presented in this paper, is used to estimate the speed, weight, and configuration of passing vehicles based on the pavement responses collected by in-situ pavement sensors. This method is still in its preliminary stage but could be very helpful in achieving real-time weigh-in-motion and traffic classification once completed in the future. A Gaussian model is used to describe the distribution of the horizontal strain induced by passing vehicles. The parameters of the Gaussian model are correlated with various loading conditions, including the weight and the configuration parameters of the passing vehicles, as proved by finite-element simulation and experimental measurements. The backcalculation process is efficient and valuable, considering the accuracy of the estimation with a low computational cost. The whole method is simple and straightforward and can be conveniently used in real-time monitoring.

The application of nanomaterials to contaminated river sediments could induce important changes in the speciation of heavy metals with potential impacts on ecosystem. Here, rhamnolipid (RL)-stabilized nanoscale zero-valent iron (RNZVI) was conducted to test its potential performance in changing the mobility and speciation of cadmium (Cd) in river sediments, with consideration of the influences of microbial community and organic carbon (OC). Compared to NZVI, RNZVI was more effective in transforming labile Cd to stable fraction with a maximum residual concentration increasing by 11.37 mg/kg after 42 days of incubation. Bacterial community structure was tracked using high-throughput sequencing of 16S rRNA genes. Results indicated that the application of RNZVI changed the bacterial community structure and increased the relative abundance of Fe(III)-reducing bacteria, which could redistribute Fe combined Cd into a more stable Fe mineral phase. The contents of OC were gradually decreased and became stable, might resulting from OC bioavailability’s being stimulated by RNZVI through changing the bacterial community composition. This study indicates that abiotic process (i.e., from reaction with NZVI) and biotic process fueled by RNZVI lead to the immobilization of Cd in river sediments.

A novel adsorbent based on steel converter slag (SCS), useful for adsorbing cationic pollutants from water was prepared by a simple method. The characterization showed that salicylic acid-methanol (SAM) modification selectively removed calcium silicate minerals from the surface of SCS and lead to a prominent increase in the specific surface areas. The maximum adsorption capacity of SAM-modified SCS for methylene blue (MB) at initial pH of 7.0 and temperature of 293 K was 41.62 mg/g, which is 35.2-times higher than that of SCS (1.15 mg/g). Adsorption kinetics and isotherms of MB on the SAM-modified SCS can be satisfactorily fitted by pseudo-second order kinetic and Langmuir model, respectively, which suggest that single-layer chemical adsorption was mainly responsible for MB removal. Further studies showed that pH value and ionic strength of wastewater have minimal effects on the adsorption capacity of SAM-modified SCS. A small decrease (10%) was found in the adsorption capacity of SAM-modified SCS after five cycles. These findings indicate that SAM-modified SCS is a promising adsorbent for the efficient removal of MB from aqueous solution due to its low cost, good thermal stability, excellent adsorption performance and simple separation.

Phosphate (P) compounds are usually used as chemical amendment for in situ remediation of heavy metal polluted sediment. However, the low deliverability, weak utilization and potential risk of eutrophication inhibit the application of most P materials. Therefore, rhamnolipid (Rha), a kind of anionic biosurfactant which has algicidal activity, was employed in this study to synthesize a new kind of nano-chlorapatite (nClAP) for Pb and Cd immobilization. Characterization results showed that the Rha stablized nClAP (Rha-nClAP) was uniformly distributed in suspensions within about 5nm. Experimental data demonstrated that the combination of Rha and nClAP could greatly enhance the Pb- and Cd-immobilization efficiencies, promoting their transformation from labile fractions to stable fractions through precipitation or adsorption processes, especially when the Rha approached to its critical micelle concentration. And Rha-nClAP could also decrease both the TCLP-leachable Pb and Cd with maximum reduction efficiencies of 98.12% and 96.24%, respectively, which also presented concentration dependence of Rha. Changes of available phosphorus implied the dissolution of nClAP during the treatment and the detection of organic matter demonstrated that the microorganisms may involve in the remediation.

Metal-free carbon nitride with controlled carbon dopants (ACCN) was synthesized by one-step copolymerization of dicyandiamide (DCD) and ammonium citrate (AC). The obtained ACCN possesses narrower band gap compared to pure graphitic carbon nitride (CN), contributing to broader utilization region of visible light. It exhibits downshifted conduction band and valence band potential with the increased addition of AC. Carbon atoms replace the bridging nitrogen atoms in the framework of ACCN during calcination process, which greatly increase its electrical conductivity and charge separation efficiency. In addition, nitrogen defects and some carbon species linked to the introduced carbon atoms are detected in ACCN. They can also serve as electrons sink to promote the separation of electron-hole pairs. As a consequence, ACCN possesses improved redox ability in the degradation of sulfamethazine (SM2) under visible light. The removal ratio by optimal ACCN achieves 81% in 60 min and its reaction apparent rate constant (0.0277 min−1) is 6.6 times higher than that of CN (0.0042 min−1). Furtherly, the mechanism and reaction process during the photocatalytic degradation are studied specifically. This work provides a facile and green strategy to prepare nonmetal modified CN with boosting photo-redox ability for pollutants treatment.

Ultrafiltration (UF) membrane modules are static in membrane tanks; thus, result in the continuous development of a cake layer and serious membrane fouling. Thickness regulation is the most convenient method to solve this owing to the looseness induced by flocs. Recently, integrated membrane technology is increasingly being applied due to its high pollutant removal efficiency and low space requirements. Herein, with the injection of Fe-based flocs, the UF membrane performance was investigated with module rotation in the presence of humic acid (HA) and south-to-north water in China. The obtained results showed that the outer cake layer was easily shed away owing to the strong flow shear force. The thickness of the cake layer decreased and membrane fouling was significantly alleviated. The faster the rotation speed, the thinner the cake layer and the lower the membrane fouling was. However, the reduction rate of the cake layer thickness decreased as the rotation speed increased owing to the high density of the inner cake layer. Although both the rotation speed and rotation time played an important role in reducing the membrane fouling, the removal efficiency of HA remained constant, and the cake layer tended to be the main fouling mechanism; thus, indicating that module rotation is beneficial to the integrated technology. Owing to the smaller particle size and higher positive charge of flocs formed under an acidic condition, more negatively charged HA molecules were adsorbed, and the UF membrane performance was superior to that in an alkaline condition. Raw water experiments further confirmed the excellent UF membrane performance. Based on this, the proposed technology has great potential for wide applications in rural areas, particularly with the rapid development of clean energy (e.g., solar energy) and intelligent water services.

Considering that the crystal facet is highly correlated with the photocatalytic performance of the semiconductor, a novel BiVO4/Ag3PO4/PANI photocatalyst combined with facet engineering and heterojunction is prepared by depositing Ag3PO4 on the highly active (0 4 0) facet of BiVO4 and then incorporating polymer polyaniline (PANI). The synergistic modification of Ag3PO4 and PANI realizes excellent photocatalytic performance, with the degradation efficiency of 85.92% and the maximum rate constant of 0.00894 L mg−1 min−1, which is 10.1, 5.6 and 1.6 times than that of BiVO4, BiVO4/PANI and BiVO4/Ag3PO4, respectively. This enhanced photocatalytic performance is attributed to the following: (i) selective exposure of highly active BiVO4 (0 4 0) facet greatly improves the spatial separation efficiency of charge carriers; (ii) the (0 4 0) facet with preferentially exposed low-coordinated oxygen atoms provides sufficient binding sites for Ag+ anchoring, resulting in strong interfacial coupling between BiVO4 and Ag3PO4, which facilitates charge separation and transfer; (iii) the CB-electrons of Ag3PO4 can be timely consumed by the VB-holes of BiVO4 by the built-in electric field, thus preventing photo-corrosion of Ag3PO4; (iv) PANI acting as hole-transfer material can rapidly migrate holes accumulated in the VB of Ag3PO4 to the catalyst surface by its HOMO orbital, thereby achieving efficient charge separation; (v) the introduction of PANI results in a significant increase in visible light absorption efficiency. This work provides a novel design based on facet engineering and heterojunction, which can also be employed to other semiconductors to improve photocatalytic performance.

The Federal Highway Administration conducted controlled loading tests on the U.S. Route 23 Test Road in hot weather conditions in Ohio, including two dual and two wide-base configurations. This paper is to reveal the influence of tyre configuration on pavement and provide some suggestions on tyre configuration from the perspective of reducing pavement damage. The raw strains were adjusted to common temperature, lateral offset distance and nominal speed for consistent comparison. MEPDG fatigue cracking and rutting models were used to predict damage brought by different tyres to pavement sections. The results indicate that newer generation of wide-based tyres with wider interface with pavement could be road-friendly, inducing similar or even less damage than the conventional dual tyres. At the same time, certain conventional dual tyres, which are commonly used in the current market, might cause larger damage to the pavement than other tyres in certain environmental and loading conditions.

The development of efficient photocatalysts for the production of hydrogen peroxide (H2O2) is a promising strategy to realize solar-to-chemical energy conversion. Graphitic carbon nitride (g-C3N4) presents giant potential for photocatalytic H2O2 production, but the sluggish charge separation depresses its photocatalytic performance. Herein, an interfacial Schottky junction composed of Ti3C2 nanosheets and porous g-C3N4 nanosheets (TC/pCN) is constructed by a facile electrostatic self-assembly route to significantly boost the spatial charge separation to promote the activation of molecular oxygen for H2O2 production. As the optimal sample, TC/pCN-2 possesses the highest H2O2 production rate (2.20 μmol L−1 min−1) under visible light irradiation (λ > 420 nm), which is about 2.1 times than that of the porous g-C3N4. The results of superoxide radical detection and rotating disk electrode measurement suggest that the two-step single-electron reduction of oxygen is the predominant reaction step during this photocatalytic H2O2 production process. The enhanced photocatalytic performance is ascribed to the formation of Schottky junction and subsequent built-in electric field at their interface, which accelerate the spatial charge separation and restrain the charge recombination. This work provides an in-depth understanding of the mechanism of photocatalytic H2O2 production, and gives ideas for the design of highly active materials for photocatalytic H2O2 production.

This work evaluated the possibility of lead (Pb2+), cadmium (Cd2+) and copper (Cu2+) ions synergic scavenging by a chloro-phosphate impregnated biochar (CPBC) from aqueous solution. Adsorption experiments displayed that the adsorption capacity of heavy metals by CPBC can be improved better compared with the pristine biochar (BC). The X-ray diffraction (XRD) analysis further demonstrated that the precipitation of Pb5(PO4)3Cl, Cd5(PO4)3Cl and Cu3(PO4)3 might be responsible for Pb2+, Cd2+ and Cu2+ scavenging. The competitive adsorption exhibited that Pb2+, Cd2+ and Cu2+ would compete for the same adsorption sites of CPBC when they coexisted and the adsorption affinity of CPBC was observed in the following order: Pb2+ > Cd2+ > Cu2+. The available phosphorus results suggested that the combination of biochar with phosphate materials can both improve the adsorption performance and reduce the risk of eutrophication by using phosphate materials which can provide a promising application for multiple heavy metals scavenging.

A novel hierarchical flower-like AgBr/Bi2WO6 Z-scheme photocatalyst was prepared through the simplified hydrothermal and deposition-precipitation method. The as-prepared photocatalysts exhibited excellent photocatalytic performance for tetracycline (TC) degradation. Especially, AgBr (20 wt%)/Bi2WO6 displayed the optimal TC removal efficiency (87.5%) within 60 min of visible light illumination. Besides, no obvious decrease in photocatalytic performance was observed after four cycles. The excellent photocatalytic performance could be ascribed to the synergistic effect between electron mediator Ag nanoparticles (Ag NPs) and Z-scheme heterojunction charge transfer mechanism, which enhanced the light harvest capability, separation efficiency of photo-generated carriers and redox ability. Moreover, three-dimensional excitation-emission matrix fluorescence spectroscopy (3D EEMs) and liquid chromatography-mass spectrometry (LC-MS) analyses shed light on the mineralization behavior and the detailed decomposition pathway of TC. This work opened up a new road to efficient Z-scheme heterojunction design and provided novel insights into antibiotics elimination mechanism in photocatalysis.

There is a continuously increasing worldwide concern for the development of wastewater and contaminated soil treatment technologies. Fenton processes and biological treatments have long been used as common technologies for treating wastewater and polluted soil but they still need to be modified because of some defects (high costs of Fenton process and long remediation time of biotreatments). This work first briefly introduced the Fenton technology and biotreatment, and then discussed the main considerations in the construction of a combined system. This review shows a critical overview of recent researches combining Fenton processes (as pre-treatment or post-treatment) with bioremediation for treatment of wastewater or polluted soil. We concluded that the combined treatment can be regarded as a novel and competitive technology. Furthermore, the outlook for potential applications of this combination in different polluted soil and wastewater, as well as the mechanism of combination was also discussed.

This paper investigated how sodium alginate (SA)-modified nanoscale zero-valent iron (NZVI), play a constructive role in the remediation of cadmium (Cd) contaminated river sediments. The changes of the fraction of Cd, enzyme activities (urease, catalase, dehydrogenase) and bacterial community structures with the treatment by SNZVI were observed. The sequential extraction experiments demonstrated that most mobile fractions of Cd were transformed into residues (the maximum residual percentage of Cd increases from 15.49% to 57.28% after 30 days of incubation at 0.1 wt% SA), with the decrease of bioavailability of Cd. Exclusive of dehydrogenase, the activities of the other two enzymes tested were enhanced with the increase of incubation time, which indicated that dehydrogenase might be inhibited by ferric ions formed from SNZVI whereas no obvious inhibition was found for other enzymes. Polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) analyses were used for the detection of microbial community changes, and the results showed that SNZVI and NZVI could increase bacterial taxa and improve bacterial abundance. All the experimental findings of this study provide new insights into the potential consequences of SNZVI treatments on the metal Cd immobilization in contaminated river sediments.

A macroporous silica-based multidentate soft-ligand 2,6-bis(5,6-di(iso-hexyl)-1,2,4-triazine-3-yl)pyridine (BDIHTP) material, BDIHTP/SiO2-P, was synthesized by impregnating and immobilizating BDIHTP into the pores of the SiO2-P particles. The adsorption behavior of some typical fission products Mo(VI), Zr(IV), Ru(III), Pd(II), Rh(III), and a part of rare earths La(III), Ce(III), Nd(III), Eu(III), Gd(III), Dy(III), Er(III), Yb(III), and Y(III) contained in highly active liquid waste (HLW) onto BDIHTP/SiO2-P was investigated. The effects of contact time and the concentration of HNO3 in the range of 0.3M to 5.0M were examined. The BDIHTP/SiO2-P materials showed excellent adsorption ability and high selectivity for Pd(II) greater than all of the tested metals. It was contributed to the effective complexation of Pd(II), a soft-Lewis acid and an electron-pair acceptor, with BDIHTP, a soft-Lewis base and an electron-pair donor. The chromatographic partitioning of the tested metals from 1.0M HNO3 by BDIHTP/SiO2-P packed column was performed. Pd(II) was effectively eluted with 0.2M thiourea-0.1M HNO3 and then separated from the others. The results are beneficial to partitioning of the long-lived minor actinides and Pd(II) together from HLW by the BDIHTP/SiO2-P materials.

A new macroporous silica-based-polymer (SiO2-P) soft ligand composite material, 2,6-bis(5,6-di(iso-butyl)-1,2,4-triazine-3-yl)pyridine (BDIBTP/SiO2-P), was synthesized by impregnation and immobilization of BDIBTP and 1-octanol molecules into the pores of the SiO2-P particles. The impact of some typical alkali metal and alkaline earths Cs(I), Na(I), K(I), Rb(I), Sr(II), and Ba(II) containing in highly active liquid waste (HLW) on the adsorption of Pd(II) onto BDIBTP/SiO2-P was studied. It was performed by examining the effects of contact time and the HNO3 concentration in the range of 0.37.0 M. BDIBTP/SiO2-P showed strong adsorption ability and high selectivity for Pd(II) over all the tested metals. The chromatographic partitioning of Pd(II) from a simulated HLW solution was conducted by BDIBTP/SiO2-P packed column. Pd(II) was effectively eluted with 0.2 M thiourea0.1 M HNO3. The others showed no adverse impact on separation of Pd(II). The results are beneficial to partitioning of minor actinides and Pd(II) together from HLW by BDIBTP/SiO2-P in the MPS process developed. (c) 2012 American Institute of Chemical Engineers AIChE J, 2012

FHWA conducted controlled loading tests on the US-23 test road in hot weather conditions in Ohio. The tests used four tire types in both dual and wide-base configurations, which were fitted on a single unit two-axle truck, maintaining a constant gross vehicle weight. Two pavement sections, one 8 in. (200 mm) and one 4 in. (100 mm) thick, were instrumented with strain gauge rosettes oriented vertically to measure strain traces induced from the passing wheel loads at three speeds and tire inflation pressures. Pavement temperature was monitored with depth during testing as well as wheel track offset distance from the strain sensors. Because of time constraints, only the sensors in the plane parallel to the direction of loading were analyzed, and response data were compared only with linear elastic pavement response models. The as-measured data were processed and evaluated for all rosettes oriented in the direction of loading. Stress relaxation modulus data were used to adjust the pavement modulus to a common temperature and loading time so all measured data could be compared at the same loading conditions. The WinLEA linear elastic model was used to determine the relationship of structural modulus to strain. Lateral offset distributions were determined from measured data to adjust all strains to the offset where maximum strain response is observed in the as-measured data. The adjustments were then applied to the as-measured strain data to make consistent comparisons between tires. Three of the four tire configurations produce nearly equivalent pavement response, which was attributed to similarities between the tire footprint widths.

Coarse aggregates in asphalt concrete should be tough and durable to withstand hot-mix asphalt production, transportation, construction, traffic loads, and environmental effects. The morphology of such aggregates plays an important role in aggregates' mechanical properties and influences asphalt pavement skid resistance, an essential characteristic of pavement performance. The predominant aggregate resources in western Virginia are carbonate rocks. The mineral components tend to be relatively soft, and when subjected to abrasive wear under traffic, the aggregate surface polishes fairly rapidly. This situation leads to smoothing of the surface and creates potential safety issues due to loss of surface friction. Considering all aspects, the increasingly popular Micro-Deval (MD) apparatus was used to assess the abrasion–polishing (A-P) resistance of coarse aggregates suspected to show a range of polishing characteristics. Although the conventional focus of the MD test is on attrition or degradation (mass loss) reflecting particles' durability, such attrition or degradation also induces a polishing effect on susceptible particles and consequently was selected for this study. Hence, a suite of carbonate and noncarbonate coarse aggregates from 10 Virginia sources was tested in the MD with the standard procedure and a cyclical A-P procedure. Also, two-dimensional digital aggregate images, before and after abrasion, were obtained and analyzed with the use of specialized software to characterize morphological parameters (shape, angularity, texture). Testing results showed that wear-resistance aggregate groupings based on the A-P procedures were consistent with the polishing tendency based on lithologic characteristics. Abrasion effects induced by both MD procedures were subjectively discernable. Trends could be perceived in the image analysis data, but the differences were not statistically verified.

MaiLuoNing injection is a traditional Chinese medicine that used clinically since the 1950s in China. However, anaphylactic reactions, through the potentiation of mast cell degranulation, have been reported. In the present study, a rat basophilic leukemia-2H3 cell membrane chromatography coupled with high-performance liquid chromatography and electrospray ionization-ion trap-time of flight-mass spectrometry method was established for screening, analyzing, and identifying the potential anaphylactic components of MaiLuoNing injection. Harpagoside, a potential degranulator of rat basophilic leukemia-2H3 cells, was retained in rat basophilic leukemia-2H3 cell membrane chromatography. We aimed to evaluate the retained components to determine which of those were capable of inducing degranulation of basophilic leukemia cells. A β-hexosaminidase assay revealed that harpagoside can induce rat basophilic leukemia-2H3 cell degranulation in a dose-dependent manner. BLBA/c mice also exhibit passive cutaneous anaphylaxis in response to harpagoside. These results indicate that rat basophilic leukemia-2H3 cell membrane chromatography coupled with high-performance liquid chromatography and electrospray ionization ion trap time-of-flight mass spectrometry is effective in screening for the anaphylactic components of MaiLuoNing injection.

To study the clinical features of acute graft-versus-host disease (aGVHD) and its risk factors for the related HLA-haploidentical non T cell-depleted in vitro peripheral hematopoietic stem cell transplantation (RHNT-PBSCT).From July 2002 to December 2012, 104 patients who underwent the RHNT-PBSCT were enrolled to analyze the incidences, location and its risk factors of aGVHD, compared with those of the 103 patients who received the HLA-matched sibling non T cell-depleted in vitro PBSCT (MSNT-PBSCT) in the same period.(1)The cumulative incidence of aGVHD in the RHNT-PBSCT group was significantly higher than the MSNT-PBSCT group [(56.2±4.7)% vs (34±3.6)%, P0.05], but the cumulative incidences of II-IV and III-IVgrade aGVHD had no significant difference between the two groups[(39.5±2.9)% vs (21.2±5.4)%, P0.05; (12.6±4.1)% vs (10.8±2.4)%, P0.05]. (2)The cumulative incidence of cutaneous aGVHD was significantly higher in RHNT-PBSCT group than that in MSNT-PBSCT group [(42.3±3.2)% vs (17.5±2.3)%, P0.05]. The cumulative incidences of liver and gastrointestinal aGVHD between the two groups had no significant difference [(7.7±2.1)% vs (12.6±3.4)%, P0.05; (16.3±4.5)% vs (10.3±2.5)%, P0.05]. (3)The 3-year disease free survival (DFS) and overall survival(OS) of RHNT-PBSCT group and MSNT-PBSCT group were (63±5.5)%, (65.2±4.7)% and (74.2±5.4)%, (77.4±5)% respectively, without significance (P=0.078, P=0.052). (4)aGVHD occurrence with HLA haplotype (P=0.003) and matched loci (P=0.002) were significantly correlated by univariate analysis. Multivariate analysis showed that only the HLA typing is a risk factor for aGVHD (HR=1.891, P=0.03).Although the incidence of total aGVHD in RHNT-PBSCT protocol is higher than that in MSNT-PBSCT, but there was no significance in severe aGVHD and cutaneous aGVHD was the common type, which indicates that RHNT-PBSCT protocol is feasible.

As one of the most important and expensive investments/assets in modern society, asphalt concrete pavements age and deteriorate with time as a result of asphalt mixture aging, cumulative loading, environmental conditions, and/or inadequate maintenance. The detection of pavement health condition is very important for a pavement analysis and management system. In this paper, a pavement health monitoring system was developed based on an embedded sensing network with an efficient combination of various commercial pavement sensors. The collected pavement responses were clear and reasonable and compared with a numerical simulation. The modulus of the pavement surface layer can be back-calculated every year or every several months based on testing runs and numerical models. Fatigue cracking and rutting models were selected to predict the distress of the experimental section according to the actual strain measurement from each passing vehicle. A health monitoring system, which contains the continuous monitoring and periodic testing as routines, is proposed as an important component of a pavement management system.

This paper presents an experimental study on the aggregate contact behavior in asphalt mixture. As a three-phase material composed of aggregates, asphalt binder, and air voids, asphalt mixture is considered as a viscoelastic material at a low stress level. The behavior of the mixture depends largely on the interaction among different components. A contact model between two aggregates is very important for understanding the deformation mechanism of the mixture. In this study, a contact model between two aggregates was reviewed in details. A closed-form time-dependent relationship between the contact forces and the relative particle/binder movements was derived. An experimental test was designed to evaluate the model which contains two elastic particles bonded by a thin layer of asphalt binder. The displacement and resistant force of the aggregate-binder system under uniaxial compression loading were documented using a cabinet X-ray tomography system. The effectiveness of the model was evaluated by ...

Aggregates used in asphalt concrete should be tough and durable to withstand hot mix asphalt (HMA) production, transportation, construction, traffic loads and environmental effects. Aggregate morphology not only plays an important role in aggregates’ mechanical properties but also influences the asphalt pavement skid resistance. The Micro-Deval apparatus, which can evaluate aggregates’ hardness or wear resistance, was used for assessing the polishing resistance of aggregates. The abrasion testing in conjunction with image analysis for aggregate shape, angularity and texture, is the focus of this study. Aggregates from ten Virginia sources were used for the Micro-Deval abrasion and digital images of twenty five particles chosen from each source were captured with a regular camera and analyzed with the MATLAB-based program to characterize the particle morphology. Due to time constraints and material availability the aggregates that were analyzed before and after abrasion were not the same aggregates. With one exception (Nolichucky quartzite), all of the aggregates exhibited very good abrasion resistance after being tested in the Micro-Deval. Also, because some of the aggregates abraded differently their morphological parameters after abrasion were larger or equal to the parameters before abrasion.