Frustrated Lewis pair catalyst realizes efficient green diesel production.

Hydrotreating renewable oils over sulfided metal catalysts is commercially applied to produce green diesel, but it requires a continuous sulfur replenishment to maintain catalyst activity, which inevitably results in sulfur contamination and increases production costs. We report a robust P-doped NiAl-oxide catalyst with frustrated Lewis pairs (i.e., P atom bonded with the O atom acts as an electron donor, while the spatially separated Ni atom acts as an electron acceptor) that allows efficient green diesel production without sulfur replenishment. The catalyst runs more than 500 h at a weight hourly space velocity (WHSV) of 28.3 h-1 without deactivation (methyl laurate as a model compound), and is able to completely convert a real feedstock of soybean oil to diesel-range hydrocarbons with selectivity >90% during 500 h of operation. This work is expected to open up a new avenue for designing non-sulfur catalysts that can make the green diesel production greener.

Investigations on the dissolved organic matter leached from oil-contaminated soils by using pyrolysis remediation method.

Pyrolysis, as a convenient and fast technology, has been proved to be promising in the remediation of oil-contaminated soil. However, little is known about the dissolved organic matter (DOM) associated with pyrolyzed oil-contaminated soil and its environmental impact. Herein, optical spectroscopic techniques (i.e., absorbance and fluorescence) were adopted to reveal the relationship between the pyrolysis temperature and the characteristics of the DOM and the associated phytotoxicity. Results show that one of the main factors determining the properties and phytotoxicity of DOM leached from the pyrolyzed soil is the critical temperature (approximately 325 °C) during pyrolysis. When the temperature was lower than 325 °C, more types and quantities of DOM, mainly fulvic acid-like substances, were desorbed from the soil with the temperature, which have little effect on wheat growth. However, when the temperature was in the range of 325-550 °C, the type and quantity of DOM increased first and then decreased as the temperature increased, during which the organic matter in the soil decomposed. The wheat growth was first inhibited and then promoted. Finally, the correlation between the spectral indices of DOM with the phytotoxicity suggested that fluorescent components identified by parallel factor analysis were positively correlated with phytotoxicity. This study indicates the pyrolytic remediation of oil-contaminated soil should avoid some critical temperature ranges.

One-Step Thermochemical Conversion of Biomass Waste into Superhydrophobic Carbon Material by Catalytic Pyrolysis.

Preparation of superhydrophobic carbon materials from lignocellulosic biomass waste via one-step carbonization is very difficult due to the existences of polar functional groups and ashes, which are extremely hydrophilic. Herein, superhydrophobic carbon materials can be facilely synthesized by catalytic pyrolysis of biomass waste using FeCl3 as catalyst. The results show that the surface energy of lignin-derived char (CharL) is significantly reduced to 19.25 mN m-1 from 73.29 mN m-1, and the water contact angle increased from 0 to 151.5°, by interaction with FeCl3. Multiple characterizations and control experiments demonstrate that FeCl3 can catalyze the pyrolytic volatiles to form a rough graphite and diamond-like carbon layer that isolates the polar functional groups and ashes on CharL, contributing to the superhydrophobicity of the CharL. The one-step catalytic pyrolysis is able to convert different natural biomass waste (e.g., lignin, cellulose, sawdust, rice husk, maize straw, and pomelo peel) into superhydrophobic carbon materials. This study contributes new information related to the interfacial chemistry during the sustainable utilization of biomass waste.

Highly stable and selective measurement of Fe3+ ions under environmentally relevant conditions via an excitation-based multiwavelength method using N, S-doped carbon dots.

Fast and accurate detection of Fe3+ under relevant natural conditions is important in environmental monitoring. In this study, an improved and simplified fluorescence method based on the multiwavelength luminescence in the visible region and the avoidance of the self-quenching property of N, S-doped carbon dots (NSC-Dots) was developed for the first time to determine Fe3+ concentration under varied environmental conditions. This method can simultaneously save time and provide accurate information. The as-prepared NSC-Dots exhibit two stable excitation peaks from 200 nm to 450 nm at a fixed emission wavelength (λem = 450 nm). A standard equation (R2 = 0.995) can be derived by measuring the quenching degree of the two peaks and referring to Stern-Volmer theory. Thus, Fe3+ concentration was accurately determined. The interference of the environmentally relevant concentrations of other metal ions, humic acid, and pH on Fe3+ measurement was tested. Results showed that the standard equation can be used to accurately determine Fe3+ concentration within the range of the 95% prediction band. The fast and facile multiwavelength method may facilitate the real-time monitoring of Fe3+ concentration in complex water environments.

The effects of environmental conditions on the enrichment of antibiotics on microplastics in simulated natural water column.

Concerns regarding the release of microplastics (MPs) into the environment led us to explore the relationship between the different environmental factors and physicochemical properties of MPs, as well as the change of interaction between MPs and organic pollutants. In this study, the effects of environmental factors (ageing conditions), such as pH, temperature, ionic strength, ageing time, and humic acid (HA) concentration, on the characteristics of MPs and their adsorption toward tetracycline (TC) were systematically investigated. The results showed that ageing factors such as pH, ionic strength, and temperature were found to have little impact on the adsorptive capacity of MPs for TC. However, MPs aged in HA solution exhibited a significant decreased adsorptive capacity for TC. HA, which has numerous functional groups, can cover the surface of MPs and change their hydrophobicity, thereby reducing the adsorption affinity to TC. The electrostatic repulsion between adsorbed HA and TC molecules may also decrease the adsorption of TC. In addition, the competing effect of HA for adsorption sites on the surface of MPs further reduces the adsorption of TC. The data presented in this work provide useful information for understanding the transfer of antibiotics by aged MPs, which is of fundamental importance to assess the environmental impact of MPs.

Remediation of Petroleum-Contaminated Soil and Simultaneous Recovery of Oil by Fast Pyrolysis.

Petroleum-contaminated soil (PCS) caused by the accidental release of crude oil into the environment, which occurs frequently during oil exploitation worldwide, needs efficient and cost-effective remediation. In this study, a fast pyrolysis technology was implemented to remediate the PCS and concurrently recover the oil. The remediation effect related to pyrolytic parameters, the recovery rate of oil and its possible formation pathway, and the physicochemical properties of the remediated PCS and its suitability for planting were systematically investigated. The results show that 50.9% carbon was recovered in oil, whose quality even exceeds that of crude oil. Both extractable total petroleum hydrocarbon (TPH) and water-soluble organic matter (SOM) in PCS were completely removed at 500 °C within 30 min. The remaining carbon in remediated PCS was determined to be in a stable and innocuous state, which has no adverse effect on wheat growth. On the basis of the systematically characterizations of initial PCS and pyrolytic products, a possible thermochemical mechanism was proposed which involves evaporation, cracking and polymerization. In addition, the energy consumption analysis and remediation effect of various PCSs indicate that fast pyrolysis is a viable and cost-effective method for PCS remediation.

The thermochemical conversion of non-lignocellulosic biomass to form biochar: A review on characterizations and mechanism elucidation.

Biochar obtained from non-lignocellulosic biomass (NLBM) has attracted wide interests in various fields like pollutants removal, catalysis, and energy storage. However, the thermochemical conversion processes from NLBM to non-lignocellulosic biochar (NLBC) have not been well summarized until now. To fill the knowledge gap, this review presents a systematical summary of NLBM characteristics, thermochemical behaviors of main components (e.g., C, O, N, P and metals), characterization methods for NLBC and conversion process, and the main applications of NLBC. Moreover, the vacancy and limitations of the current researches are pointed out to provide some guidance for future study. This review would contribute to deepen the understanding of NLBC, meanwhile optimize the efficient disposal and value-added utilization of NLBM wastes via thermochemical conversion.

Thermochemical behavior of tris(2-butoxyethyl) phosphate (TBEP) during co-pyrolysis with biomass.

Co-pyrolysis of plastic waste and wood biomass to recover valuable chemicals is a cost-effective waste-recycling technology. However, widely used organophosphate ester additives in plastic, such as tris(2-butoxyethyl) phosphate (TBEP), can form diverse phosphorus (P)-containing species. These P-containing compounds can pose new environmental challenges when the biochar is reused. In this study, a mixture of TBEP and lignin was used to simulate the feedstock of plastic waste and wood biomass, and the thermochemical behavior of TBEP in slow pyrolysis (20 K min(-1)) and fast pyrolysis at 400-600 °C was investigated. The results show that low temperature in fast pyrolysis favors the enrichment of P in char. Up to 76.6% of initial P in the feedstock is retained in the char resulting from 400 °C, while only 51% is retained in the char from 600 °C. Slow pyrolysis favors the formation of stable P species regardless of the temperature; only 7% of the P retained in the char is extractable from char from slow pyrolysis, while 20-40% of P can be extracted from char resulting from fast pyrolysis. The addition of CaCl2 and MgCl2 can significantly increase the fraction of P retained in the char by the formation of Ca, Mg-P compounds. Online TG-FTIR-MS analysis suggests that TBEP undergoes decomposition through different temperature-dependent pathways. The P-containing radicals react with the aromatic rings produced by the pyrolysis of lignin to form Ar-P species, which is an important factor influencing the distribution and stabilization of P in char.

Expression and clinical significance of myeloid derived suppressor cells in chronic hepatitis B patients.

We here document discovery of expression profile of myeloid derived suppressor cells (MDSCs) in chronic hepatitis B (CHB) patients and changes in the course of disease. The study population was composed of 75 outpatient HBV cases and 15 healthy control cases. Peripheral blood samples were collected for separation of mononuclear cells. Levels of MDSCs labeled with Lin-DR-CD11b+CD33+ obtained from peripheral blood mononuclear cells (PBMC), were revealed to have significant differences between the CHB and other groups. They were 0.414% for health control cases and 0.226% for CHB cases (Z=-2.356, p=0.0189). It also observed that the group of HBeAg positive cases had significant difference in MDSCs/ PBMC median (X(2)=11.877, p=0.003), compared with group of HBeAg negative cases and the healthy control group. It suggested considerable MDSCs might be involved in HBeAg immune tolerance. In addition, negative correlations between MDSCs/PBMC and parameters of ALT, AST and TBil, while positive correlation between MDSCs/ PBMC and ALB parameter were found. Multiple comparisons between the four phases and health control phase again, there was a statistically sifnificant difference (X(2)=17.198, p=0.002). Taken together, these findings may provide a new immunotherapy strategy for reduced the expression levels of MDSCs in CHB patients, through induction of an autoimmune response to virus removal.

Epithelial-mesenchymal transition in colorectal cancer tissue of patients with Lynch syndrome.

AIM: To explore the epithelial-mesenchymal transition (EMT) in tissue from patients with Lynch syndrome, and to interpret biological behaviour of Lynch syndrome. METHODS: Sixty-eight formalin-fixed and paraffin embedded tissue blocks were analyzed in this study, including tissues from Lynch syndrome (n = 30), sporadic colorectal carcinoma (CRC) (n = 30), and tumor-adjacent tissues (n = 8). Tissue sections were stained for human mutS homolog 2 (hMSH2), human mutL homolog 1 (hMLH1), transforming growth factor-ß type II receptor (TGFßRII), E-cadherin, ß-catenin, matrix metalloproteinase-7 (MMP-7) and tissue inhibitor of metalloproteinase-2 (TIMP-2) by immunohistochemical staining. Furthermore, clinical data such as age, gender and tumor-node-metastasis stage were also collected retrospectively. RESULTS: The positive expression rates of hMSH2, hMLH1, TGFßRII, E-cadherin, ß-catenin, MMP-7 and TIMP-2 were significantly related to the depth of invasion and lymph node metastasis, but not to sex or tumour size or location. The differences in the positive expression rates of hMSH2, hMLH1, TGFßRII, E-cadherin, cytomembrane ß-catenin, cytoplasmic ß-catenin, MMP-7 and TIMP-2 were significant between sporadic CRC and Lynch syndrome. The expression of hMSH2 had a positive correlation with that of hMLH1 in Lynch syndrome and sporadic CRC. The expression of TGFßRII had a positive correlation with that of hMSH2, hMLH1 and MMP-7, and a negative correlation with that of TIMP-2. The expression of MMP-7 had a negative correlation with that of TIMP-2 in Lynch syndrome and sporadic CRC. The expression of E-cadherin was positively correlated with that of cytomembrane ß-catenin. However, the expression of cytomembrane ß-catenin was negatively correlated with that of cytoplasmic ß-catenin, and the expression of cytoplasmic ß-catenin was positively correlated with that of MMP-7. CONCLUSION: EMT may play an important role in the development and progression of Lynch syndrome. Lynch syndrome was caused by the mutations of mismatch repair genes, mainly hMSH2 and hMLH1, which also beget the mutational inactivation of TGFßRII. Therefore, the colorectal cancer of Lynch syndrome can escape the inhibitory effect of TGFß1. However, TGFß1 can up-regulate the expression of MMP-7 and down-regulate the expression of TIMP-2 in tumors by disassembling the E-cadherin/ß-catenin complex in the cytomembrane.

Synchronous rectal and gastric cancer in a fighter pilot: aeromedical concerns.

Synchronous cancer of the stomach and rectum is very rare. In a special population of pilots, especially fighter pilots, synchronous rectal and gastric cancer is much more uncommon. We herein report a case of synchronous carcinoma of the rectum and stomach. The patient was a 44-year-old male fighter pilot who complained with bloody stool and altered bowel habits. He was diagnosed with hereditary nonpolyposis colorectal cancer with a definite family history, and subsequently he underwent simultaneous low anterior resection and distal gastrectomy with D2 lymphadenectomy. Postoperative pathologic assessment showed a poorly differentiated gastric adenocarcinoma with signet ring cell components (pT2N1M0; stage IIb) and a moderately differentiated rectal adenocarcinoma with myxoid components (pT3N0M0; stage IIa). Both tumors showed positive expression of p53, Ki-67, VEGF, carcinoembryonic antigen, MRP, TS, P-gp, and TopoII, and negative expression of c-erbB2, CD34, CD31, D2-40, S-100, FVIII, MLH1, MSH2, and MSH6 oncoproteins. Six cycles of XELOX chemotherapy and 50 Gy/25 f radiotherapy were delivered postoperatively. Now, he has returned to his work under medical observation for about 6 months. From this patient's diagnosis and treatment, we think that the gene screening should be used in pilot selection. According to the result of gene screening, we can give pertinence examinations to the target organ of genes. It is very necessary for pilots to keep keen vigilance at gastrointestinal tumors because they have to face many high-risk factors in working. As to pilots, the selection of operation should be individualized.

[An improved BALB/c 3T3 cell transformation assay and its application in the cocarcinogenesis study].

OBJECTIVE: To improve the protocol of BALB/c 3T3 cell transformation assay, and apply it to the cocarcinogenesis study. METHOD: Appropriate serum concentration, culture media and method of administration were selected by testing their effects on the growth and transformation of BALB/c 3T3 cells. The co-carcinogenic activity between diethylnitrosamine (DEN) and microcystin-LR (MC-LR) or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were examined using the improved cell transformation assay. The malignant characteristics of transformed cells were verified by neoplasia in SCID mice. RESULTS: There were strong co-carcinogenic activity between DEN and TCDD. On the contrary, although MC-LR has strong ability to induce cell transformation, the effect was markely inhibited by DEN. The transformed cells show some malignant characteristics. CONCLUSION: The improved BALB/c 3T3 cell transformation assay is reliable and time-saving, and can be efficiently used in the study of cocarcinogenesis.

Sclerosing mesenteritis as a rare cause of abdominal pain and intraabdominal mass: a cases report and review of the literature.

Sclerosing mesenteritis is a rare, benign, and chronic fibrosing inflammation disease with unknown etiology that affects the mesentery of small bowel and colon. The disease has two well-established histological types: the acute or subacute form known as mesenteric panniculitis and the chronic form known as retractile or sclerosing mesenteritis. Because the sclerosing mesenteritis is lack of special clinical manifestation and typical signs, so the patients are very easy to be misdiagnosed. The correct diagnosis of sclerosing mesenteritis depends on pathological examination and exploratory laparotomy. We report a case of sclerosing mesenteritis in a 52-year-old male who presented with chronic abdominal pain and intraabdominal mass. This patient had a long-term and heavy drinking history. He was misdiagnosed as celiac teratoma by CT examination and then underwent an exploratory laparotomy at March 2 2004. A mass, its diameter being about 5 cm, was detected in mesentery of distal ileum. Although a few small intestines tightly adhered on the mass, the involved intestine had no obstruction. The intraoperative biopsy indicated that it was an inflammatory mass. The mass and adhered intestines were removed. He was diagnosed with sclerosing mesenteritis by histopathological examination of paraffin section. After operation, this patient went well and lives without recrudescence at the time we wrote this paper.

Determination of trace mercury by solid substrate-room temperature phosphorimetry quenching method based on catalytic effect of Hg2+ on formation of the ion association complex [Sn(XO)6]4+.[(Fin)4].

A new method for the determination of trace mercury by solid substrate-room temperature phosphorimetry (SS-RTP) quenching method has been established. In glycine-HCl buffer solution, xylenol orange (XO) can react with Sn4+ to form the complex [Sn(XO)6]4+. [Sn(XO)6]4+ can interact with Fin- (fluorescein anion) to form the ion associate [Sn(XO)6]4+.[(Fin)4]-, which can emit strong and stable room temperature phosphorescence (RTP) on polyamide membrane (PAM). Hg2+ can catalyze H2O2 oxidizing the ion association complex [Sn(XO)6]4+.[(Fin)4]-, which causes the RTP to quench. The DeltaIp value is directly proportional to the concentration of Hg2+ in the range of 0.016-1.6 fg spot(-1) (corresponding concentration: 0.040-4.0 pg ml(-1), 0.40 microl spot(-1)), and the regression equation of working cure is DeltaIp=10.03+83.15 m Hg2+ (fg spot(-1)), (r=0.9987, n=6) and the detection limit (LD) is 3.6 ag spot(-1)(corresponding concentration: 9.0 x 10(-15) g ml(-1), the sample volume: 0.4 microl). This simple, rapid, accurate method is of high selectivity and good repeatability, and it has been successfully applied to the determination of trace mercury in real samples. The reaction mechanism for catalyzing H2O2 oxidizing the ion association complex ([Sn(XO)6]4+.[(Fin)4]-) SS-RTP quenching method to determine trace mercury is also discussed.