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Purpose: To introduce a method of cranial bone reconstruction for cranial burst fractures and early-stage growing skull fractures, named bone flap binding and transposition. Methods: Cranial burst fractures, severe head injuries predominantly observed in infants, are characterized by widely diastatic skull fractures coupled with acute extracranial cerebral herniation beneath an intact scalp through ruptured dura mater. These injuries can develop into growing skull fractures. This study included two cases to illustrate the procedure, with a particular focus on the bone steps in managing these conditions. The medical history, clinical presentation, surgical procedures, and postoperative follow-up were retrospectively studied. The details of the surgical procedure were described. Results: The method of bone reconstruction, named bone flap binding and transposition, was applied after the lacerated dural repair. Two bone pieces were combined to eliminate the diastatic bone defect and then fixed by an absorbable cranial fixation clip and bound by sutures. The combined bone flap was repositioned into the bone window, completely covering the area of the original dural laceration. Subsequently, the bone defect was transferred to the area of normal dura. The postoperative courses for the two infants were uneventful. Follow-up CT scans revealed new bone formation at the previous bone defect and no progressive growing skull fracture. The major cranial defects had disappeared, leaving only small residual defects at the corners of the skull bone window, which required further recovery and did not affect the solidity of the skull. Conclusion: Bone flap binding and transposition provide a straightforward, cost-effective, and reliable method for cranial bone reconstruction of cranial burst fractures and early-stage growing skull fractures. This method has taken full advantage of the small infant's dura osteogenic potential without the need for artificial or metallic bone repair materials. The effectiveness of the method needs further validation with more cases in the future. [ABSTRACT FROM AUTHOR]

With the development of information technology, the high-speed private data stream encryption transmission system is more and more widely used in the field of education. The high-speed private data stream encryption transmission system can realize high-speed and safe data transmission and protect the privacy and security of user data. To protect the security of private data in the online education of specialty "traffic engineering", an encryption transmission system for high-speed private data stream is designed. After the online education system and core modules of traffic engineering are analyzed, the system framework is designed through the codec module and the high-speed privacy data stream processing control and transmission module. The sliding window segmentation method is used to extract the privacy data in the education system and send it to the coding sub-module. Based on a homomorphic encryption algorithm, a private data stream encryption and decryption model is established. The key encoding is designed by the vector quantization coding method. The private data is authenticated according to the characteristics of the key, and the data encryption transmission is completed through the microcontroller. The experimental results show that the encrypted data of the designed system has only 0.01 Gbit loss, and the encryption time is only 93ms. The data dimension displayed after encryption is relatively scattered, and the distribution probability of encrypted data is between 1500–2000, which can effectively encrypt the private data in the online education system of transportation engineering specialty, and improve the security of high-speed private data flow in the online education system of transportation engineering specialty. [ABSTRACT FROM AUTHOR]

We have designed a novel device that facilitates the accurate placement of occipital ventricular catheters in ventriculoperitoneal shunt procedures. After 7 years of clinical use, this device has consistently demonstrated its simplicity, user-friendliness, and effectiveness. It enables both experienced surgeons and novices to confidently and accurately position the ventricular catheter to a satisfactory location. [ABSTRACT FROM AUTHOR]

Purpose: Children diagnosed with suprasellar arachnoid cysts often concurrently have hydrocephalus. This study aims to classify the relationship between suprasellar arachnoid cysts and hydrocephalus, discussing surgical strategies—shunting or neuroendoscopic approaches—and their sequence, based on this classification.A retrospective analysis was conducted on 14 patients diagnosed with suprasellar arachnoid cysts and hydrocephalus, treated surgically by the first author between January 2016 and December 2020. Clinical features, radiological findings, surgical strategies, and outcomes were reviewed. The classification of the relationship between the suprasellar arachnoid cysts and hydrocephalus was developed and illustrated with specific cases. Recommendations for future surgical management based on this classification are provided.We classified the relationship between suprasellar arachnoid cysts and hydrocephalus into three categories. SACH-R1, the direct type, represents cases where the cysts cause obstructive hydrocephalus. Here, neuroendoscopic ventriculocystocisternostomy (VCC) effectively treats both conditions. SACH-R2, the juxtaposed type, involves concurrent occurrences of cysts and hydrocephalus without a causative link. This is further subdivided into SACH-R2a, where acute progressive communicating hydrocephalus coexists with the cyst, initially managed with a ventriculoperitoneal shunt, followed by VCC upon stabilization of hydrocephalus; and SACH-R2b, where the cyst coexists with chronic stable communicating hydrocephalus, first addressed with VCC, followed by monitoring and potential secondary shunting if needed. Key factors differentiating SACH-R2a from SACH-R2b include the patient's age, imaging signs of fourth ventricle and cisterna magna enlargement, and the rapid progression or chronic stability and severity of hydrocephalus symptoms. SACH-R3, the reverse type, describes scenarios where shunting for hydrocephalus leads to the development or enlargement of the cyst, managed via neuroendoscopic VCC with precautions to prevent infections in existing shunt systems.The simultaneous presence of suprasellar arachnoid cysts and hydrocephalus requires a nuanced understanding of their complex relationship for optimal surgical intervention. The analysis and classification of their relationship are crucial for determining appropriate surgical approaches, including the choice and sequence of shunting and neuroendoscopic techniques. Treatment should be tailored to the specific type identified, rather than blindly opting for neuroendoscopy. Particularly for SACH-R2a cases, we recommend initial ventriculoperitoneal shunting.Methods: Children diagnosed with suprasellar arachnoid cysts often concurrently have hydrocephalus. This study aims to classify the relationship between suprasellar arachnoid cysts and hydrocephalus, discussing surgical strategies—shunting or neuroendoscopic approaches—and their sequence, based on this classification.A retrospective analysis was conducted on 14 patients diagnosed with suprasellar arachnoid cysts and hydrocephalus, treated surgically by the first author between January 2016 and December 2020. Clinical features, radiological findings, surgical strategies, and outcomes were reviewed. The classification of the relationship between the suprasellar arachnoid cysts and hydrocephalus was developed and illustrated with specific cases. Recommendations for future surgical management based on this classification are provided.We classified the relationship between suprasellar arachnoid cysts and hydrocephalus into three categories. SACH-R1, the direct type, represents cases where the cysts cause obstructive hydrocephalus. Here, neuroendoscopic ventriculocystocisternostomy (VCC) effectively treats both conditions. SACH-R2, the juxtaposed type, involves concurrent occurrences of cysts and hydrocephalus without a causative link. This is further subdivided into SACH-R2a, where acute progressive communicating hydrocephalus coexists with the cyst, initially managed with a ventriculoperitoneal shunt, followed by VCC upon stabilization of hydrocephalus; and SACH-R2b, where the cyst coexists with chronic stable communicating hydrocephalus, first addressed with VCC, followed by monitoring and potential secondary shunting if needed. Key factors differentiating SACH-R2a from SACH-R2b include the patient's age, imaging signs of fourth ventricle and cisterna magna enlargement, and the rapid progression or chronic stability and severity of hydrocephalus symptoms. SACH-R3, the reverse type, describes scenarios where shunting for hydrocephalus leads to the development or enlargement of the cyst, managed via neuroendoscopic VCC with precautions to prevent infections in existing shunt systems.The simultaneous presence of suprasellar arachnoid cysts and hydrocephalus requires a nuanced understanding of their complex relationship for optimal surgical intervention. The analysis and classification of their relationship are crucial for determining appropriate surgical approaches, including the choice and sequence of shunting and neuroendoscopic techniques. Treatment should be tailored to the specific type identified, rather than blindly opting for neuroendoscopy. Particularly for SACH-R2a cases, we recommend initial ventriculoperitoneal shunting.Results: Children diagnosed with suprasellar arachnoid cysts often concurrently have hydrocephalus. This study aims to classify the relationship between suprasellar arachnoid cysts and hydrocephalus, discussing surgical strategies—shunting or neuroendoscopic approaches—and their sequence, based on this classification.A retrospective analysis was conducted on 14 patients diagnosed with suprasellar arachnoid cysts and hydrocephalus, treated surgically by the first author between January 2016 and December 2020. Clinical features, radiological findings, surgical strategies, and outcomes were reviewed. The classification of the relationship between the suprasellar arachnoid cysts and hydrocephalus was developed and illustrated with specific cases. Recommendations for future surgical management based on this classification are provided.We classified the relationship between suprasellar arachnoid cysts and hydrocephalus into three categories. SACH-R1, the direct type, represents cases where the cysts cause obstructive hydrocephalus. Here, neuroendoscopic ventriculocystocisternostomy (VCC) effectively treats both conditions. SACH-R2, the juxtaposed type, involves concurrent occurrences of cysts and hydrocephalus without a causative link. This is further subdivided into SACH-R2a, where acute progressive communicating hydrocephalus coexists with the cyst, initially managed with a ventriculoperitoneal shunt, followed by VCC upon stabilization of hydrocephalus; and SACH-R2b, where the cyst coexists with chronic stable communicating hydrocephalus, first addressed with VCC, followed by monitoring and potential secondary shunting if needed. Key factors differentiating SACH-R2a from SACH-R2b include the patient's age, imaging signs of fourth ventricle and cisterna magna enlargement, and the rapid progression or chronic stability and severity of hydrocephalus symptoms. SACH-R3, the reverse type, describes scenarios where shunting for hydrocephalus leads to the development or enlargement of the cyst, managed via neuroendoscopic VCC with precautions to prevent infections in existing shunt systems.The simultaneous presence of suprasellar arachnoid cysts and hydrocephalus requires a nuanced understanding of their complex relationship for optimal surgical intervention. The analysis and classification of their relationship are crucial for determining appropriate surgical approaches, including the choice and sequence of shunting and neuroendoscopic techniques. Treatment should be tailored to the specific type identified, rather than blindly opting for neuroendoscopy. Particularly for SACH-R2a cases, we recommend initial ventriculoperitoneal shunting.Conclusion: Children diagnosed with suprasellar arachnoid cysts often concurrently have hydrocephalus. This study aims to classify the relationship between suprasellar arachnoid cysts and hydrocephalus, discussing surgical strategies—shunting or neuroendoscopic approaches—and their sequence, based on this classification.A retrospective analysis was conducted on 14 patients diagnosed with suprasellar arachnoid cysts and hydrocephalus, treated surgically by the first author between January 2016 and December 2020. Clinical features, radiological findings, surgical strategies, and outcomes were reviewed. The classification of the relationship between the suprasellar arachnoid cysts and hydrocephalus was developed and illustrated with specific cases. Recommendations for future surgical management based on this classification are provided.We classified the relationship between suprasellar arachnoid cysts and hydrocephalus into three categories. SACH-R1, the direct type, represents cases where the cysts cause obstructive hydrocephalus. Here, neuroendoscopic ventriculocystocisternostomy (VCC) effectively treats both conditions. SACH-R2, the juxtaposed type, involves concurrent occurrences of cysts and hydrocephalus without a causative link. This is further subdivided into SACH-R2a, where acute progressive communicating hydrocephalus coexists with the cyst, initially managed with a ventriculoperitoneal shunt, followed by VCC upon stabilization of hydrocephalus; and SACH-R2b, where the cyst coexists with chronic stable communicating hydrocephalus, first addressed with VCC, followed by monitoring and potential secondary shunting if needed. Key factors differentiating SACH-R2a from SACH-R2b include the patient's age, imaging signs of fourth ventricle and cisterna magna enlargement, and the rapid progression or chronic stability and severity of hydrocephalus symptoms. SACH-R3, the reverse type, describes scenarios where shunting for hydrocephalus leads to the development or enlargement of the cyst, managed via neuroendoscopic VCC with precautions to prevent infections in existing shunt systems.The simultaneous presence of suprasellar arachnoid cysts and hydrocephalus requires a nuanced understanding of their complex relationship for optimal surgical intervention. The analysis and classification of their relationship are crucial for determining appropriate surgical approaches, including the choice and sequence of shunting and neuroendoscopic techniques. Treatment should be tailored to the specific type identified, rather than blindly opting for neuroendoscopy. Particularly for SACH-R2a cases, we recommend initial ventriculoperitoneal shunting. [ABSTRACT FROM AUTHOR]

Spent lithium-ion battery recycling has attracted significant attention because of its importance in regard to the environment and resource importance. Traditional hydrometallurgical methods usually leach all valuable metals and subsequently extract target meals to prepare corresponding materials. However, Li recovery in these processes requires lengthy operational procedures, and the recovery efficiency is low. In this research, we demonstrate a method to selectively recover lithium before the leaching of other elements by introducing a hydrothermal treatment. Approximately 90% of Li is leached from high-Ni layered oxide cathode powders, while consuming a nearly stoichiometric amount of hydrogen ions. With this selective recovery of Li, the transition metals remain as solid residue hydroxides or oxides. Furthermore, the extraction of Li is found to be highly dependent on the content of transition metals in the cathode materials. A high leaching selectivity of Li (> 98%) and nearly 95% leaching efficiency of Li can be reached with LiNi0.8Co0.1Mn0.1O2. In this case, both the energy and material consumption during the proposed Li recovery is significantly decreased compared to traditional methods; furthermore, the proposed method makes full use of H+ to leach Li+. This research is expected to provide new understanding for selectively recovering metal from secondary resources. [ABSTRACT FROM AUTHOR]

A series of Ni/HZSM-5 and Ni/HIM-5 bi-functional catalysts were synthesized and applied to the aqueous-phase hydrodeoxygenation (HDO) of phenol. The Ni dispersibility and particle sizes were shown to be directly related to the porosity and crystal sizes of the parent zeolites, which further influenced the catalytic performances. The large pores and small crystal sizes of the parent zeolites were beneficial for dispersing Ni and forming small Ni particles, and the corresponding Ni/zeolite catalyst exhibited a higher phenol conversion and selectivity towards hydrocarbons. Importantly, the Ni/HIM-5 bi-functional catalyst exhibited a high activity (98.3%) and high selectivity for hydrocarbons (98.8%) when heated at 220°C for 1 h and is thus a new potential catalyst for the HDO of phenolics to form hydrocarbons in the aqueous phase. [ABSTRACT FROM AUTHOR]

In the production of lithium-ion batteries (LIBs) and recycling of spent LIBs, a large amount of low-concentration lithium-containing wastewater (LCW) is generated. The recovery of Li from this medium has attracted significant global attention from both the environmental and economic perspectives. To achieve effective Li recycling, the features of impurity removal and the interactions among different ions must be understood. However, it is generally difficult to ensure highly efficient removal of impurity ions while retaining Li in the solution for further recovery. In this study, the removal of typical impurity ions from LCW and the interactions between these species were systematically investigated from the thermodynamic and kinetics aspects. It was found that the main impurities (e.g., Fe3+, Al3+, Ca2+, and Mg2+) could be efficiently removed with high Li recovery by controlling the ionic strength of the solution. The mechanisms of Fe3+, Al3+, Ca2+, and Mg2+ removal were investigated to identify the controlling steps and reaction kinetics. It was found that the precipitates are formed by a zero-order reaction, and the activation energies tend to be low with a sequence of fast chemical reactions that reach equilibrium very quickly. Moreover, this study focused on Li loss during removal of the impurities, and the corresponding removal rates of Fe3+, Al3+, Ca2+, and Mg2+ were found to be 99.8%, 99.5%, 99%, and 99.7%, respectively. Consequently, high-purity Li3PO4 was obtained via one-step precipitation. Thus, this research demonstrates a potential route for the effective recovery of Li from low-concentration LCW and for the appropriate treatment of acidic LCW. [ABSTRACT FROM AUTHOR]

An appropriate co-catalyst can significantly promote the photocatalytic efficacy, but this has been seldom studied in the visible-light photocatalysis combined with ozone, namely photocatalytic ozonation. In this work, a dendritic bismuth vanadium tetraoxide (BiVO4) material composited with highly dispersed MnOx nanoparticles was synthesized, and its catalytic activity is 86.6% higher than bare BiVO4 in a visible light and ozone combined process. Catalytic ozonation experiments, ultraviolet- visible (UV-Vis) diffuse reflectance spectra and photoluminescence spectra jointly indicate that MnOx plays a triple role in this process. MnOx strengthens the light adsorption and promotes the charge separation on the composite material, and it also shows good activity in catalytic ozonation. The key reactive species in this process is $OH, and various pathways for its generation in this process is proposed. This work provides a new direction of catalyst preparation and pushes forward the application of photocatalytic ozonation in water treatment. [ABSTRACT FROM AUTHOR]

Ion exchange process is an alternative technique for removal of heavy metal ions from industrial wastewater. The main aim of this paper is to evaluate the performance of different ion exchange resins in removing Cr(VI) from wastewater. The effects of resin types and dosage, initial pH were examined systemically. The results showed that the performance of different resins had obvious difference for the removal of the Cr(VI) ions, in which the type of functional groups of the resin was the main factor. The SEM images indicated that the micro-morphology of resins before and after adsorption of the Cr(VI) presented a little difference. The EDS analysis showed that the adsorbed Cr(VI) was uniformly distributed at the surface of the resins with formation of oxygen-containing groups. The adsorption isotherms and kinetics of Cr(VI) by the different resins are also discussed. [ABSTRACT FROM AUTHOR]

The extraction mechanism and the oxidation of extractants are essential to optimize the extraction process. To investigate the two problems for selective extraction of V(V) and Cr(VI), the extraction complexes of V(V) and Cr(VI) formed in the process of extraction with primary amines were obtained by solvent-out crystallization, respectively. The average compositions of the extraction complexes were determined by element analysis, X-ray photoelectron spectroscopy, and inductive couple plasma-optical emission spectrometry. The chemical functional groups of the extraction complexes were confirmed by Fourier transform infrared spectroscopy and Raman spectroscopy. The structures of the extraction complexes of V(V) were speculated with their functional groups and average compositions. The hydrogen bond association mechanism of V(V) extraction was illustrated with the structure of the complexes, and the oxidation reaction of extractants with Cr(VI) was also demonstrated. According to the oxidation reaction of extractants with Cr(VI) and experiment conditions for the initial pH value, the optimized operation condition of the initial pH value ≥5.5 was determined to prevent the oxidation of extractants. The interaction of V(V) and Cr(VI) for the vanadium extraction and extractant oxidation was also investigated. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Leaching selectivity during metal recovery from complex electronic waste using a hydrochemical process is always one of the generic issues. It was recently improved by using ammonia-based leaching process, specifically for electronic waste enriched with copper. This research proposes electrodeposition as the subsequent approach to effectively recover copper from the solutions after selective leaching of the electronic waste and focuses on recognising the electrochemical features of copper recovery. The electrochemical reactions were investigated by considering the effects of copper concentration, scan rate and ammonium salts. The diffusion coefficient, charge transfer coefficient and heterogeneous reaction constant of the electrodeposition process were evaluated in accordance with different solution conditions. The results have shown that electrochemical recovery of copper from ammoniabased solution under the conditions of selective electronic waste treatment is charge transfer controlled and provide bases to correlate the kinetic parameters with further optimisation of the selective recovery of metals from electronic waste. [ABSTRACT FROM AUTHOR]

Panax notoginseng ( P. notoginseng) is a well-known traditional Chinese medicinal herb. Due to elevated arsenic (As) levels in some planting area, P. notoginseng and its derivatives are contaminated, and the As concentration in these products exceeds the standard limit (As concentration < 2 mg/kg). In this study, the effects of sulfate (S) application on As uptake and the physicological response of P. notoginseng were investigated in a pot-culture experiment. The results showed that the As concentration in the roots was significantly decreased by a maximum of 64.9 % in response to the application of 75 mg/kg S. The proportion of methylated arsenic, which is less toxic, in the roots was increased by 263.4 %. Moreover, the application of S alleviated the oxidative damage due to As stress, and the activities of superoxide dismutase (SOD) and peroxidase (POD) were improved by 26.2 and 29.4 %, respectively. Finally, the total saponin content in the roots increased by 26.0 % in response to a supply of 50 mg/kg S. These findings implied that the application of S fertilizer could effectively reduce As accumulation in P. notoginseng and promote the formation of pharmaceutical components. [ABSTRACT FROM AUTHOR]

This work presented the results of tungstic precipitation from NaWO-NaSO-HO system at 293.15 K, with which the Pitzer parameters of $$\beta _{N{a_2}W{O_4}}^{\left( 0 \right)}$$ and $$\beta _{N{a_2}W{O_4}}^{\left( 1 \right)}$$ were determined from Pitzer equation by regression. Thus the mean ionic activity coefficients of sodium tungstate were calculated. The obtained $$\beta _{N{a_2}W{O_4}}^{\left( 0 \right)}$$ and $$\beta _{N{a_2}W{O_4}}^{\left( 1 \right)}$$ were substituted as fixed values in extraction modeling from NaWO-HSO-HO system by primary amine (N1923) in toluene as diluent. Meanwhile the activity coefficient expressions in organic phase were varied based on Pitzer theory that the interaction term for the solvent should not be included. The Pitzer parameters for organic phase were re-regressed in order to make the model more accurate. The average absolute relative deviation (AARD) for calculated and experimental molality of WO in aqueous phase was 5.24%. The results showed that the model can not only correlate but also predict the liquid-liquid equilibrium (LLE) data. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) contamination has been reported to be a problem for the safe usage of Panax notoginseng (Sanchi); thus, it is necessary to elucidate the Cd accumulation in Sanchi and to assess its associated health risk. Samples were collected from major producing areas in Yunnan, China. The average concentration of Cd in Sanchi was 0.43 mg/kg, which exceeds the standard level for herbal medicine in China (0.3 mg/kg). A stepwise regression analysis showed that zinc and the pH were the related factors that most significantly impacted Cd in Sanchi roots. The hazard quotient values were estimated as 0.0010 (men) and 0.0012 (women) for consumers taking preparations and were 0.011 (men) and 0.013 (women) for consumers taking health products, implying that there is no non-carcinogenic hazard associated with Sanchi consumption. However, a Monte Carlo simulation showed that approximately 0.80 % of male and 1.02 % of female consumers via drug consumption and 36.28 % of male and 41.87 % of female consumers via health product consumption had an exposure exceeding the acceptable daily intake (ADI) of Cd from drugs (1 % of the total oral ADI as suggested by the World Health Organization). These people should control their oral Cd intake from both Sanchi consumption and diet as a whole. [ABSTRACT FROM AUTHOR]

Ternary Ag nanoparticles (NPs)@polyoxometalate (POM)/reduced graphene oxide (rGO) nanohybrids were prepared by a facile photoreduction method, using POM as the photocatalyst, reducing and bridging molecules. The structure of the nanohybrids was characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, Raman spectroscopy, etc. Most importantly, both the rotating disk electrode and rotating ring-disk electrode tests indicated that the Ag NPs@POM/rGO nanohybrids exhibited excellent electrocatalytic activity towards oxygen reduction reaction via a direct four-electron transfer pathway due to the synergistic effect of Ag NPs and rGO. [ABSTRACT FROM AUTHOR]

The thermodynamic model of the extraction of W with primary amine under near neutral conditions is reported in this paper. The activity coefficients of the nonelectrolytes in organic phase are calculated by the Margules and NRTL equations which are based on previously tested liquid-liquid extraction equilibrium data in combination with mass balances and charge balance formula. The activity coefficients of the electrolytes in aqueous phase are calculated by the Pitzer equation. The thermodynamic model of the extraction of W by a primary amine is constructed from the calculated activity coefficients of electrolytes and nonelectrolytes. The extraction of W using primary amine is also predicated, and the data is compared to the calculated results of the thermodynamic model. It is concluded that Margules equation proves to be suitable and reliable for calculating the activity coefficients of nonelectrolytes in complex organic phase systems. [ABSTRACT FROM AUTHOR]

The mechanisms responsible for the fast granulation of anaerobic sludge caused by Mg and Ca addition was examined in four lab-scale expanded granular sludge bed (EGSB) reactors. Results indicated that both Mg and Ca accelerated the sludge-granulation process and increased the amount of polysaccharides and proteins in the sludge. Energy dispersive x-ray spectrometry (EDX) analysis revealed that, in a mature granule, both Mg and Ca composed as phosphate and calcium was distributed primarily in the periphery of the granule, while magnesium distributed mainly in the interior. The addition of Mg was more favorable for the nuclei formation, whereas the addition of Ca was more favorable for subgranule growth and maintaining the granules' rigid structure. Results showed that the addition of Mg in the nuclei formation stage and Ca in the granule-growth stage accelerated granulation more than adding only one of them in the granulation process. [ABSTRACT FROM AUTHOR]

Purpose: Frequent mining activities and higher background values in soil have led to the contamination of the sediments of some rivers in southwest China by several metals and arsenic (As). This study combined multivariate analysis with geochemical approaches to differentiate mining activity from other sources, which may aid to evaluate the effectiveness of reducing mining release. Materials and methods: Sixteen sediment samples were collected along the Yuan River, China. The total concentrations of lead (Pb), zinc (Zn), copper (Cu), cadmium (Cd), chromium (Cr), mercury (Hg), and As were measured by inductively coupled plasma-atomic emission spectrometer (ICP-AES). The Pb isotopic composition was measured using a thermal ionization mass spectrometer (TIMES). Both geochemical approaches and multivariate statistical analysis were used to identify the sources of these metals. The fractionation of Pb was determined through a Community Bureau of Reference (BCR) sequential extraction procedure to aid the identification of the sources. Results and discussion: The concentrations and enrichment factors (EFs) of Pb, Zn, Cu, Cd, and As in the middle reach of the river were higher than those at the other sites, indicating anthropogenic sources. The factor analysis (FA) extracted 'mining and smelting,' 'mixture of anthropogenic and natural,' and 'natural' factors. The Pb isotope composition of metal ores was similar (Pb/Pb < 1.190 and Pb/Pb > 2.023) to that found in the sediments in the middle reach, indicating anthropogenic sources of mining activities. Compared with the narrow ranges of the δS ratios in the bedrock (+8.5 to +9.3 ‰) and the metal ores (−1.4 to +1.9 ‰), the sediment samples presented a relatively wide range of δS ratios from −2.6 to +9.2 ‰ with a mean of +2.6 ‰, which suggests a mixed composition. The BCR sequential extraction procedure revealed that the proportion of the extractable fraction in the sediments in the middle reach was higher than that in other sites, suggesting anthropogenic sources as the cause of contamination in the study area. Conclusions: Lead, Zn, Cu, Cd, Cr, Hg, and As are mainly derived from natural materials in the upstream region. In the middle reach, these elements are the result of anthropogenic activities, particularly activities associated with the mining industry. In the downstream region, the origin of these elements is considered to be a mixture of anthropogenic and natural sources. In addition to geochemical approaches and multivariate statistical analysis, the BCR sequential extraction method is an effective procedure for the identification of the anthropogenic sources of sediment-associated metals. [ABSTRACT FROM AUTHOR]

Given that the consumption of organic substances entails costly biodesulfurization, the characteristics of the bacterial community in a reactor should be determined to increase the desulfurizing rate under low organic loading condition. In this study, the bacterial community distribution in the expanded granular sludge bed reactor used to treat sulfate-containing wastewater with low organic loading rate was determined by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and 16S rDNA clone library analyses. DGGE results showed that the predominant bacteria were stable and accounted for ~90 % sulfate removal efficiency. Differences in band positions and intensities indicated that the distribution and abundance of bacteria were affected by their positions in the reactor. Typical bands were identified in the bacterial community comprising Desulfovibrio, Desulfomicrobium, Thiomonas, Acinetobacter, Bacteroidetes, and Chloroflexi. Their functions in the reactor were also discussed. The possible links between the functional and microbial responses were also investigated based on the characteristic and spatial distribution of each bacterium in consortium. [ABSTRACT FROM AUTHOR]

In this paper, composite coagulants (PFS, PFSC05, PFSC1 and PFSC5), prepared by mixing polyferric sulfate (PFS) and cationic polyelectrolyte (CP) coagulants with different weight percent ( Wp) of CP ( Wp = 0%, 0.5%, 1% and 5%, respectively), were adopted to treat cyanide-containing wastewater. PFSC5 exhibited superior coagulation performances at optimal conditions: the removal of total cyanide (TCN) and chemical oxygen demand (COD) was 95%–97% and 50%–55%, respectively. The effects of CP on the properties and structure of flocs were investigated by laser diffraction instrument and small-angle laser light scattering (SALLS), respectively. The results show that the flocs of PFSC5 have higher growth rate, higher strength factor and lower recovery factor than other flocs. They are also much denser and more uniform owing to the higher fractal dimension (D f) and less microflocs (10–100 μm). Furthermore, the dense structure of the PFSC5 flocs can be restored after shear and is more resistant to hydraulic conditions. Particularly, detailed morphology evolution of the flocs was in-situ detected by on-line particle imaging. Due to strong ionic strength in wastewater, the CP in PFSC5 plays a significant role of adsorption, while the main mechanism of CP is electrostatic patch aggregation during the PFSC05 systems. [ABSTRACT FROM AUTHOR]

A double layered, one-pot hydrothermal method was adopted in this work to prepare transition metal ions (Fe 3+, Ni 2+, Cu 2+ and Co 2+) doped TiO 2. The morphology and chemical properties of TiO 2 and the status of metal ions were characterized with XRD, TEM, BET, UV-Vis and XPS analysis. TEM images show that the obtained TiO 2 was very uniform with an average particle size of 10.4 nm. XPS, TEM and XRD results show that transitional metals were doped onto TiO 2 in the form of ions. Photocatalytic decomposition of oxalic acid under UV illumination and methylene blue degradation under visible light on these materials were conducted, respectively. The results reveal that Cu 2+-TiO 2 and Co 2+-TiO 2 showed a highest activity under UV and visible light illumination, respectively, and they were both more active than commercial P25 TiO 2. With this special design of double layers, the hydrolysis of titanium precursor in the system with water can be easily controlled and metal ions are simply doped. This strategy can be further applied to synthesize metal ion doped TiO 2 using various metal precursors with controllable amounts, and thus lead to better optimization of highly active photocatalyst. [ABSTRACT FROM AUTHOR]

This paper aims to make an overview on the current status and new tendency for recycling cathodic active materials from spent lithium-ion batteries. Firstly, it introduces several kinds of pretreatment technologies, followed by the summary of all kinds of single recycling processes mainly focusing on organic acid leaching and synergistic extraction. Then, several examples of typical combined processes and industrial recycling processes are presented in detail. Meanwhile, the advantages, disadvantages and prospect of each single process, combined process, as well as industrial recycling processes, are discussed. Finally, based on a novel acidic organic solvent, the authors briefly introduce an environmental friendly process to directly recycle and resynthesize cathodic active material LiNi 1/3Co 1/3Mn 1/3O 2 from spent lithium-ion batteries. The preliminary experimental results demonstrated the advantages of low reaction temperature, high separation efficiency and organic solvent cycling and preventing secondary pollution to the environment. This process may be used for large-scale recycling of spent lithium-ion batteries after further study. [ABSTRACT FROM AUTHOR]

In this study, a novel horizontal rotating soil washing process and equipment were developed and tested for pilot-scale remediation of soils from a site polluted by chromium ore process residue. Operating parameters, including cylinder rotational velocity, cylinder tilt angle, heating temperature and liquid/soil ratio, were investigated. The Taguchi method was used for the experiment design, and the standard L16 orthogonal array with four parameters and four levels was selected for optimising the operating parameters. Optimal removal efficiency was achieved at cylinder rotational velocity of 2.5 rpm, cylinder tilt angle of 2.6°, heating temperature of 200 °C and liquid/soil ratio of 8. The efficiency of citric acid as an extractant in the novel process was compared with that of water. The analysis of the residual Cr(VI) concentration of the soil shows that citric acid could efficiently remove 22.89 % more Cr(VI) than water in one-stage washing. The residual Cr(VI) concentration in the soil after the three-stage washing is as low as 26.16 mg/kg, which meets the screening levels for soil environmental risk assessment of sites in Beijing City (30 mg/kg). Further study is currently underway to optimise the novel process and equipment for commercial-scale use. [ABSTRACT FROM AUTHOR]

A novel technique for internal structure and elemental distribution analyses of granular sludge is presented. Sludge samples were freeze-dried and embedded in epoxy resin to form a module, which were then ground and polished to obtain sequential cross-sections. The cross-sections were analyzed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). SEM observations showed that one granule was formed having several cores with different inorganic minerals, rather than a single core. EDX results indicate that the main elements of the granules are O, Ca, Mg, and P. In addition, the distribution areas of calcium and magnesium in the granule do not coincide. [ABSTRACT FROM AUTHOR]

Sulfate reducing bacteria (SRB) is identified as the primary organisms responsible for the treatment of heavy metal wastewater. However, most heavy metals can inhibit the growth of SRB during heavy metal treatment processes. Sulfide is a metabolic product of SRB and it can precipitate or reduce heavy metals. This study focused on the effects of sulfide on SRB resistance to Cu(II), Hg(I) and Cr(VI) toxicity. First, we considered the existence style of various heavy metals with and without sulfide addition by sequential extraction experiments. Second, the particle size distribution was evaluated and the cell structure during the metabolism of a SRB culture, containing different heavy metals, was analyzed by particle size distribution and TEM analyses. Third, the evolution of sulfate under the influence of different concentrations of heavy metals with and without sulfide addition was investigated to evaluate SRB activity. The results indicated that sulfide played an important role in alleviating and even eliminating the toxicity of Cu(II), Hg(II) and Cr(VI). We also discuss the mechanism of sulfide on SRB resistance to Cu(II), Hg(I) and Cr(VI) toxicity. [ABSTRACT FROM AUTHOR]

large volume of bacterially produced precipitates are generated during the bio-treatment of heavy metal wastewater. The composition of the bacterially produced precipitates and its effects on sulfate reducing bacteria (SRB) in copper-containing waste stream were evaluated in this study. The elemental composition of the microbial precipitate was studied using electrodispersive X-ray spectroscopy (EDX), and it was found that the ratio of S:Cu was 1.12. Combining with the results of copper distribution in the SRB metabolism culture, which was analyzed by the sequential extraction procedure, copper in the precipitates was determined as covellite (CuS). The bacterially produced precipitates caused a decrease of the sulfate reduction rate, and the more precipitates were generated, the lower the sulfate reduction rate was. The particle sizes of bacterially generated covellite were ranging from 0.03 to 2 μm by particles size distribution (PSD) analysis, which was smaller than that of the SRB cells. Transmission electron microscopy (TEM) analysis showed that the microbial covellite was deposited on the surface of the cell. The effects of the microbial precipitate on SRB metabolism were found to be weakened by increasing the precipitation time and adding microbial polymeric substances in later experiments. These results provided direct evidence that the SRB activity was inhibited by the bacterially produced covellite, which enveloped the bacterium and thus affected the metabolism of SRB on mass transfer. [ABSTRACT FROM AUTHOR]

Water blown rigid polyurethane foams with different functionality were prepared. The physical properties of rigid foams were measured with rotational viscometer (NDJ-1), universal testing machine (Instron3365), scanning electron microscope (SEM) and differential scanning calorimeter (DSC). The results show that the viscosity of polyether polyol increases exponentially from 62 mPa·s to 6 000 mPa·s with the increase of functionality from 2 to 5.6, respectively. The overall density of foam increases slightly from 31.7 kg/m3 to 37.4 kg/m3 with increasing functionality while core density exhibited little difference. Compressive strength of foam shows the similar behavior with density except for 2-functional sample. At the same time, dimensional stability becomes better with increasing functionality except for 5.6-functional foam that has worse stability than 4.8-functional foam. From the SEM results, the functionality is not an important factor in determining distribution of cell size of foam. According to the results of thermal analysis, the glass transition temperature ( T g) shifts to a higher temperature from 128.9 ° to 166.3 ° for the 2 to 5.6 functional foam, respectively. [ABSTRACT FROM AUTHOR]

Rigid polyurethane foams blown by varying water level were prepared in this study. The structures and physical properties of rigid polyurethane foams blown by water were measured with FT-IR, universal testing machine (Instron3365), scanning electron microscope (SEM) and differential scanning calorimeter (DSC). The results show that polyurea and polybiuret were the typical characteristics, and the cream time and gel time were shorter for the fully water blown rigid foam than that for the fully cyclopentane blown foams. The density of foam samples decreased from 45.0 kg/m3 to 27.4 kg/m3 with the increase of water level from 3 pph to 7 pph. Compressive strength exhibited the similar behavior with density. The average cell size of foam samples ranged from 241 μm to 356 μm with the increase of water level from 3 pph to 7 pph, respectively. At the same time, poorer dimensional stability was encountered with the increase of average cell size due to fast diffusion rate of CO2 out of the foam. The results of thermal analysis show that the glass transition temperature ( T g) shifted to a higher temperature with the increase of isocyanate level when more water was used as chemical blowing agent. [ABSTRACT FROM AUTHOR]

Osteopontin (OPN) is a secreted phosphoglycoprotein that has been linked to tumor progression and survival in several solid tumors, including head and neck cancers. Previous studies showed that OPN expression is induced by tumor hypoxia, and its plasma levels can serve as a surrogate marker for tumor hypoxia and treatment outcome in head and neck cancer patients. In this study, we investigate the transcriptional mechanism by which hypoxia enhances OPN expression. We found that OPN is induced in head and neck squamous cell carcinoma (HNSCC) cell lines and in NIH3T3 cells by hypoxia at both mRNA and protein levels in a time-dependent manner. Actinomycin D chase experiments showed that hypoxic induction of OPN was not due to increased mRNA stability. Deletion analyses of the mouse OPN promoter regions indicated that a ras-activated enhancer (RAE) located at −731 to −712 relative to the transcription start site was essential for hypoxia-enhanced OPN transcription. Using electrophoretic mobility shift assays with the RAE DNA sequence, we found that hypoxia induced sequence-specific DNA-binding complexes. Furthermore, hypoxia and ras exposure resulted in an additive induction of OPN protein and mRNA levels that appeared to be mediated by the RAE. Induction of OPN through the RAE element by hypoxia is mediated by an Akt-kinase signaled pathway as decreasing Akt levels with dominant negative constructs resulted in inhibition of OPN induction by hypoxia. Taken together, these results have identified a new hypoxia responsive transcriptional enhancer that is regulated by Akt signaling.Oncogene (2005) 24, 6555–6563. doi:10.1038/sj.onc.1208800; published online 20 June 2005 [ABSTRACT FROM AUTHOR]

Investigates the metabolism, population dynamics and spatial distribution of nitrifying bacteria and heterotrops in biofilms. Use of direct electric current and the micro-slicing technique; Inhibition of the nitrification rate by a current over 10 Am-2 at lower C/N ratios; Significant decrease in bacterial density of nitrifying bacteria in surface biofilms; Finding that an increase in current density narrowed the inner biofilm region; Changes in the density of NQ2-oxidizers and NH1-oxidizers in the surface biofilms, suggesting dectrochemical reactions at the anode; Finding that the current's effect on population dynamics and spatial distribution was less significant at larger C/N ratios.