壳聚糖基镍铝水滑石的制备及吸附性能

本文采用微波辅助合成壳聚糖基Ni-Al水滑石(LDHs),研究了焙烧水滑石(C-LDHs)以及未焙烧水滑石(LDHs)对水溶液中氟离子的吸附行为,以壳聚糖基Ni-Al水滑石为吸附剂,研究了吸附剂用量、pH值、干扰离子、焙烧温度等对水中氟离子吸附的影响。同时用X射线衍射(XRD)和红外分析(FTIR)对LDHs以及吸附氟离子后的LDHs的结构和性质进行了表征,并且对样品进行了热重差热(TG-DTA)和透射电镜(TEM)分析。结果表明:Ni-Al水滑石的焙烧温度过高会导致水滑石的层状结构被破坏,原样的吸附性能优于焙烧产物的吸附性能。低浓度氟离子有利于水滑石的吸附,吸附剂用量为0.2 g/L,吸附率达到85.78%,pH值在6~7之间吸附氟离子效果最佳,强酸和强碱环境都不利于吸附氟离子。

Recent progress and future prospects of oil-absorbing materials

Oil and organic solvent contamination, derived from oil spills and organic solvent leakage, has been recognized as one of the major environmental issues imposing a serious threat to both human and ecosystem health. Among the various presented technologies applied for oil/water separation, oil absorption process has been explored widely and offers satisfactory results especially with surface modified oil-absorbing material and/or hybrid absorbents. In this review, we summarize the recent research activities involved in the designing strategies of oil-absorbing absorbents and their application in oil absorption. Then, an extensive list of various oil-absorbing materials from literature, including polymer materials, porous inorganic materials and biomass materials, has been compiled and the oil adsorption capacities toward various types of oils and organic solvents as available in the literature are presented along with highlighting and discussing the various factors involved in the designing of oil-absorbing absorbents tested so far for oil/water separation. Finally, some future trends and perspectives in oil-absorbing material are outlined.

Ni_2P/ZrO_2-SBA-15 Dibenzothiophene Hydrodesulfurization Catalysts: Preparation,Characterization and Evaluation

Ni_2P/ZrO_2-SBA-15 catalysts with different zirconium n-propoxide/SBA-15 mass ratios were synthesized to evaluate their dibenzothiophene hydrodesulfurization catalytic activity. Effect of ZrO_2 introduction was investigated. Supports and catalysts were characterized by BET,XRD,^(29)SiNMR,XPS and FTIR. The results indicated that zirconium was incorporated into SBA-15 in the forms of [(–O–)_2 Si(–O–Zr)_2 ] and/or [(–O–)_3 Si–O–Zr],and that the SBA-15 framework structure was maintained after incorporation of ZrO_2. With zirconium content increasing,ZrO_2 was transformed from amorphous phase to tetragonal phase. Zirconium incorporation into SBA-15 supports could facilitate to form more dispersed Ni_2P active phase. There might be some interaction occurring between the P and Zr species. In addition to Ni_2P,another kind of active phase,ZrP,was formed,which might exhibit a better HDS activity than Ni_2P. It was observed that at a temperature of 280 °C,pressure of 3.0 MPa,WHSV of 6.5 h^(-1) and H_2 to oil ratio of 450,the Ni_2P/Zr-SBA(1.5) catalyst,where 1.5 represents zirconium n-propoxide/SBA-15 mass ratio,showed the highest DBT conversion,which was 86.6%,almost 35% higher than that of the Ni_2P/Zr-SBA(0) catalyst.

Effect of Non-Thermal Plasma Modified NiAl Layered Double Hydroxides on the Removal of Fluoride from Aqueous Solution

In this paper, NiAl layered double hydroxides (NiAl-LDHs) has been modified by non-thermal plasma (NTP) to enhance the fluoride removal capacity of materials. The samples were characterized by X-ray diffraction, Fourier transform infrared spectrometer (FTIR), Thermogravimetric differential thermal analyzer (TG-DTA) and N2 adsorption-desorption. Effects of pH, co-existing anions, temperature and kinetics on F﹣ adsorption were investigated. The results showed that pH affects the adsorbent surface charge. The effective pH range for F﹣ removal was between 4.5 and 10. Lower pH potentially causes dissolution of NiAl-LDHs. The negligible interference of coexisting ions such as makes the NiAl-LDHs a promising sorbent for fluoride polluted water treatment.

Diverse Ring-seco Limonoids from Munronia unifoliolata and Their Biological Activities

Twenty-two new limonoids,mufolinoids A—V(1—22),including six rings A,B-seco limonoids(1—6),twelve ring A-seco limonoids(7—18),four ring-intact limonoids(19—22),together with thirteen known compounds(23—35)were isolated from Munronia unifoliolata.Their structures including absolute configurations were elucidated by combination of NMR,HR-MS,single-crystal X-ray diffraction and calculations of ECD and NMR technologies.Compounds 24,25,33,34 could be significantly reversed the multidrug resistance of MCF-7/doxorubicin(DOX)cells,and the reversal fold(RF)was much higher than that of positive drug Verapamil.Compounds 24,28,and 29 exhibited significant anti-inflammatory activity with the IC50 values in the range of 17.7—39.4μmol/L.Furthermore,compound 29 could markedly inhibit the release of IL-1βby inhibiting the initiation and assembly of NLRP3 inflammasome,which demonstrates the great potential of limonoids as an anti-inflammatory agent.

Gut microbiota and its implications in small bowel transplantation

The gut microbiota is mainly composed of a diverse population of commensal bacterial species and plays a pivotal role in the maintenance of intestinal homeostasis, immune modulation and metabofism. The influence of the gut microbiota on solid organ transplantation has recently been recognized. In fact, several studies indicated that acute and chronic allograft rejection in small bowel transplantation （SBT） is closely associated with the alterations in microbial patterns in the gut. In this review, we focused on the recent findings regarding alterations in the microbiota following SBT and the potential roles of these alterations in the development of acute and chronic allograft rejection. We also reviewed important advances with respect to the interplays between the microbiota and host immune systems in SBT. Furthermore, we explored the potential of the gut microbiota as a microbial marker and/or therapeutic target for the predication and intervention of allografl rejection and chronic dysfunction. Given that current research on the gut microbiota has become increasingly sophisticated and comprehensive, large cohort studies employing metagenomic analysis and multivariate linkage should be designed for the characterization of host-microbe interaction and causality between microbiota alterations and clinical outcomes in SBT. The findings are expected to provide valuable insights into the role of gut microbiota in the development of allograft rejection and other transplant-related complications and introduce novel therapeutic targets and treatment approaches in clinical practice.

Mufolinin A,an unprecedented ring A-seco 10-ethyllimonoid from Munronia unifoliolata

Mufolinin A(1),a ring A-seco rearranged limonoid with an unprecedented ethyl at C-10 and novel 6/6/6/5 fused-ring skeleton,together with three new potential precursors(ring A-seco limonoids,2–4)were isolated from Munronia unifoliolata.Their structures and absolute configurations were confirmed by nuclear magnetic resonance(NMR),high resolution electrospray ionization mass spectroscopy(HRESIMS),X-ray crystallography,electronic circular dichroism(ECD)calculations and NMR calculations with DP4+analyses.The unprecedented ethyl group of 1 was hypothesized to be derived from methyl migration and ring reduction rearrangement of ring A-seco limonoid 4.Compounds 2 and 4 showed significant multidrug resistance(MDR)reversal activities in MCF-7/DOX cells with reversal fold(RF)values of 13.1 and 8.0,respectively.

The response of intestinal stem cells and epithelium after alemtuzumab administration

Qiurong Li1,Qiang Zhang1,Chenyang Wang1,Shaojun Jiang2,Ning Li1,Jieshou Li1 Intestinal stem cells may have important roles in the maintenance of epithelial integrity during tissue repair.Alemtuzumab is a humanized anti-CD52 lymphocytic antibody that is increasingly being used to induce immunosuppression;intestinal barrier function is impaired during treatment with alemtuzumab.We investigated the response of intestinal stem cells to epithelial damage resulting from alemtuzumab treatment.Intestinal epithelial cell loss and abnormal Paneth cell morphology were found following a single dose of alemtuzumab.The animals receiving alemtuzumab exhibited increased apoptosis in the villi 3 days after alemtuzumab treatment and in the crypt on day 9,but apoptosis was scarce on day 35.We assessed expression of Musashi-1-and Lgr5-positive stem cells following alemtuzumab treatment.Increased numbers of cells staining positive for both Musashi-1 and Lgr5 were found in the stem cell zone after alemtuzumab treatment for 3 and 9 days.These data indicated that the epithelial cells were injured following alemtuzumab treatment,with the associated expansion of intestinal stem cells.After alemtuzumab treatment for 35 days,the numbers of intestinal epithelial cells and intestinal stem cells returned to normal.This study suggests that alemtuzumab treatment induced the increase in stem cells,resulting in the availability of more enterocytes for repair.