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TiO(2) was prepared by a hydrothermal method at a low temperature and used to degrade and mineralize dimethyl phthalate (DMP). TiO(2) was characterized by XRD, TEM, BET and UV-vis techniques. The characteristics of TiO(2) prepared by a hydrothermal method (h-t TiO(2)) included a good crystalline anatase phase, greater surface area, stronger absorption to UV light wavelength and lower agglomeration than TiO(2) prepared by a classic sol-gel method (s-g TiO(2)). The photocatalytic activity of h-t TiO(2) prepared under optimal hydrothermal condition (180°C for 10h) was 2.5 times higher than that of s-g TiO(2) in degrading DMP. The process of photocatalysis combined with UV irradiation and ozonation (TiO(2)/UV/O(3)) considerably improved the mineralization and degradation of DMP compared to photocatalysis combined with UV irradiation (TiO(2)/UV), ozonation combined with UV irradiation (UV/O(3)), and ozonation alone (O(3)). A kinetic study showed the mineralization in TiO(2)/UV/O(3) followed the Langmuir-Hinshelwood model.

A modified synthesis approach for spherical large pore-diameter SBA-15 mesoporous silica (SLP-SBA-15) with particle size range of 0.5–1 μm was being reported. It was worth mentioning that in this improved methodology, the use of cetyltrimethylammonium bromide (CTAB) as co-template significantly reduced the self-assembly time from 24 h to 45 min. Moreover, under reflux condition, the reaction time could be further shortened by reducing the aging time from 48 h to 6 h. The resultant SLP-SBA-15 was thereafter successfully functionalized and packed into an ultra-high-performance liquid chromatography (UHPLC) column for the separation of aromatic compounds. A variety of characterizations demonstrated that the silica products exhibited a well-ordered 2d hexagonal mesostructure with well-formed spherical morphology. pore-diameter can be enlarged up to 8.2 nm without affecting the structural order. The SLP-SBA-15 samples showed excellent thermal and hydrothermal stabilities. The octadecyltriethoxysilane functionalized SLP-SBA-15 (SLP-C18-SBA-15) was demonstrated to be an effective stationary phase in UHPLC application because the column exhibited significantly reduced column pressure (2800 psi) at a flow rate of 0.4 ml/min. Accordingly, it would afford greater flexibility for tuning of the flow rate to meet the fast separation requirement.

A novel native beta-cyclodextrin chiral stationary phase was prepared via "click" chemistry with cuprous iodide-triphenylphosphine complex as the catalyst and applied for enantioseparation of Dns-amino acids, substituted phenyl and phenoxy group modified propionic acids, flavonoids, and some pharmaceutical compounds such as nimodipine, propranolol, brompheniramine and bendroflumethiazide in reversed-phase high-performance liquid chromatography. The studied analytes could be resolved under different separation conditions. The resolution of Dns-DL-Leu could reach 5.08 using a mobile phase consisting of 1% (w/w) triethylammonium acetate buffer (pH 4.11) and methanol (50:50 v/v). The effects of buffer pH and the content of organic modifier on enantioseparation of Dns-amino acids by this novel chiral phase were being investigated. The separation results demonstrate that click chemistry, a versatile reaction, affords a facile approach towards the preparation of stable chiral stationary phases.

The chromatographic behavior of purine derivatives on a new cucurbit [6] uril monorotaxane-bonded silica stationary phase (CB6MRBS) was studied using high performance liquid chromatography both under normal and reversed-phase modes. A comparative study of this phase with ODS was carried out as well. The influences of methanol content, pH value and ionic strength of mobile phases were investigated in detail. The results showed that various interactions occurred between the analytes and CB6MRBS besides hydrophobic interaction under reversed-phase were different from those on ODS. According to the chromatographic analysis, the separation mechanism of multiple interactions also exists under normal phase. The CB6MRBS can provide various sites for analytes, such as the hydrophobic, hydrogen-bonding, pi-pi and dipole-dipole interactions. Separations of purine derivatives on CB6MRBS were achieved with satisfaction due to the various retention mechanisms both under reversed- and normal phase modes.

A curcumin bonded silica stationary phase (CCSP) for high performance liquid chromatography was prepared by using gamma-glycidoxypropyltrimethoxysilane (KH-560) as coupling reagent. Its structure was characterized by elemental analysis, Fourier transform infrared spectroscopy and thermal analysis. The chromatographic performance and the retention mechanism on the new packing material were evaluated by using neutral, acidic and basic compounds as solute probes and methanol-water as binary mobile phases. A comparative study with ODS was carried out as well. The results showed that CCSP appeared to be excellent reversed-phase stationary phase with versatile chromatographic functions. The curcumin ligand bonded on silica gel can provide n-pi and pi-pi action sites for different analytes because of its integrated conjugated system. Additionally, the polar hydroxyl and carbonyl groups of curcumin facilitated dipoledipole and hydrogen-bonding interactions between the ligand and solutes in the effective separation process. In comparison with ODS, CCSP has the advantages in fast separation of polar compounds because of its weaker hydrophobicity and various synergistic sites.

A new preparation method of 3,5-dinitrobenzoyl-bonded silica gel stationary phase (DNB) for high performance liquid chromatography has been developed by using N-(beta-aminoethyl)-gamma-aminopropyl-methyldimethoxy silane as coupling reagent. Its structure was characterized by elemental analysis, diffuse reflectance Fourier transform infrared spectroscopy and thermal analysis. The surface concentration of 3,5-dinitrobenzoyl ligand was 2.08 micromol/m2 according to the carbon content from elemental analysis. The chromatographic performance of the new packing was evaluated by using different solute probes, such as polycyclic aromatic hydrocarbons (PAHs), phenols, naphthalene derivatives, nitrophenol positional isomers and sulfonamides. The results show that comparing with ODS, DNB has weaker hydrophobicity and more versatile chromatographic properties. The charge-transfer between the dinitrobenzoyl ligand and the analytes plays a significant role in the separation of phenols and naphthalene derivatives. In addition, static electric, hydrogen-bonding and dipole-dipole interactions are responsible for the above separations and improve the selectivity of DNB for solutes. An advantage of DNB is that it is suitable for the separation of the basic compounds containing nitrogen atoms without capped process because the spacer containing nitrogen atoms can shield the residual silanols on DNB.

TiO2/UV/O3-BAC (biological activated carbon) process was employed to treat raw water and compared to UV/O3-BAC process in its optimum parameters (3 mg/L ozone dosage with 15 min oxidation time and 15 min empty bed contact time in BAC). The results showed that the presence of TiO2 improved ozone utilization and biodegradability of the effluent. For the dissolved organic carbon (DOC) removal, TiO2/UV/O3-BAC was more efficient than UV/O3-BAC and its synergetic effect is more than that in UV/O(3)-BAC process. It was showed that small molecules with MW3000 Da predominated in the raw water accounting for more than 56% DOC, they were increased after oxidation, accounting for more than 64% DOC. GC/MS analysis showed that TiO2/UV/O3-BAC process was effective in removing phthalate esters (PAEs) and persistent organic pollutants (POPs). PAEs' removal ratio reached more than 94% and reduced with the increase of the length of the alkyl side chains and the alkyl branch chains. TiO2/UV/O3-BAC process was also very effective in removing POPs. Polybromobiphenyls' removal rate reached more than 89% and decreased with the increase of substitutional bromines except for 2,2',5,5'-tetrabromobiphenyl, which can be completely removed.

AC (activated carbon)/O3–BAC (biological activated carbon) process was employed to treat secondary effluent and compared to O3–BAC process. The effects of ozone dosages and empty bed contact time (EBCT) in BAC on dissolved organic carbon (DOC) removal were investigated. The results showed that the presence of AC improved ozone utilization and biodegradability of the effluent. DOC removal increased with ozone dosage and EBCT in BAC, however, 3 mg l−1 ozone dosage with 15 min oxidation time and 15 min EBCT in BAC were more economical and efficient. For DOC removal, AC/O3–BAC was more efficient than O3–BAC and its synergetic effect was more than that in O3–BAC process. The biomass of the subsequent BAC unit in AC/O3–BAC process was more than that in O3–BAC process and much more than that in BAC alone. Except for organic pollutants with molecular weight (MW) >10 kDa, those of other MW range were decomposed much more by AC/O3 process than by O3 process. GC/MS analysis showed that dibutyl phthalate, bis(2-ethylhexyl) phthalate, 4-bromo-3-chloroaniline, 2-propanone-ethylhydrazone and phenol derivatives were prevalent organic compounds in the secondary effluent. Some aromatic compounds, such as 4-bromo-3-chloroaniline and 2,4-dichloro-benzenamine disappeared after AC/O3 treatment. However, some small molecules were generated, after further biological treatment by BAC, the kinds and concentration of organic compounds were greatly reduced.

A p-tert-butyl-calix[6]-1,4-benzocrown-4-bonded silica gel stationary phase (CR6BS) was first prepared via 3-glycidoxypropyltrimethoxysilane as coupling reagent for high performance liquid chromatography. The structure of the new stationary phase was characterized by diffuse reflectance infrared fourier transform spectroscopy (DRIFT), elemental analysis and thermal analysis. The chromatographic performance of the bonded-stationary phase was evaluated by using neutral, acidic and basic solutes as probes. Meanwhile, comparative study of the new stationary phase with a p-tert-butyl-calix[6]arene-bonded silica gel stationary phase (C6BS, the parent) and ODS was done under the same chromatographic conditions. The results show that the new stationary phase has an excellent reversed-phase property, which is similar to C6BS and ODS. However, the selectivities for some aromatic compounds are different from the parent phase (C6BS) and ODS, especially the latter. In one hand, as hybrid of calixarene and crown ether, CR6BS with the oxygen atoms of ether-bridge can provide the complexation sites for the solutes, lacking of C6BS. On the other hand, the rigid conformation of CR6BS may be responsible to the different performance partially. CR6BS exhibits high selectivity in the separation of alkylated aromatics from their parents as compared with C6BS.

Beta-cyclodextrin, p-tert-butyl-calix[8]arene and chloropropyl bonded silica stationary phases have been prepared and were applied at the same time to develop a chromatographic procedure to separate steroids. In order to select the best type of stationary phase for the analysis, similar preparation processes of the two kinds of macrocycle stationary phases with the same spacer were adopted respectively. The chromatographic behaviors and retention mechanisms of the two kinds of macrocycle stationary phases for steroids were systematically studied and compared with those of chloropropyl bonded silica and ODS. The effect of mobile phase variables, such as methanol content, pH value of buffer, ionic strength and buffer composition on chromatographic behaviors was investigated. The results showed that the retention mechanisms of the four stationary phases for steroids were obviously different, and excellent separation was achieved on beta-cyclodextrin bonded silica stationary phase (beta-CD-BS), as a consequence of the structure and the properties of the stationary phase. The retention process on beta-CD-BS exhibited inclusion complexation, hydrogen-bonding and weak hydrophobic interaction, while for p-tert-butyl-calix[8]arene bonded silica stationary phase (CBS), pi-pi and hydrogen-bonding besides hydrophobic interaction played an important role.

A new p-tert-butyl-calix[8]arene-bonded silica gel stationary phase (CABS) was prepared via 3-glycidoxypropyltrimethoxysilane as a coupling reagent for HPLC. Its structure was characterized by diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), elemental analysis and thermal analysis. The chromatographic performance of new packing was evaluated by using basic, acidic and neutral aromatic compounds as probes compared with conventional ODS. The results show that the new stationary phase has an excellent reversed-phase property and high selectivities for substituted aromatics compared with ODS, because CABS can provide various sites for the analytes, such as hydrogen-bonding interactions, pi-pi interactions, and inclusion complex, besides hydrophobic interactions.

In this paper, the chromatographic behavior of some water-soluble vitamins was studied on a new p-tert-butyl-calix[8]arene-bonded silica gel stationary phase (CABS, 5mum particle size, the bonded amount 0.071mmolg(-1)) by using vitamin standards as probes for HPLC. The comparative study of the separation of these compounds was done by using CABS and ODS as stationary phases under the same chromatographic conditions. The better separation of six vitamins including: B(1), B(2), B(6), B(12), C, and nicotinic acid (B(5)), on CABS can be achieved by using isocratic mode with methanol-phosphate buffer (25:75, (v/v)) as mobile phase within 20min. The results show that the calix[8]arene-bonded phase exhibits high selectivity for water-soluble vitamins. We found that the elution order of B(2) (12.08min) and B(12) (16.42min) on CABS was very different from that of B(12) (7.76min) and B(2) (18.47min) on ODS, which indicate that different retention mechanisms exist in the chromatographic processes of the two stationary phases. According to the chromatographic data, it can be concluded that various chromatographic retention mechanisms are responsible for the separation of above compounds on CABS, such as hydrophobic interaction, hydrogen bonding interaction, and pi-pi interaction. The new packing has two advantages over ODS. On one hand, the polar and ionized analytes, such as C and B(5), exhibited stronger affinities to CABS because of hydrogen bonding interaction. On the other hand, the retention of B(2) and B(12) became shorter on CABS with weaker hydrophobicity in comparison with ODS. The new material exhibits the promising application in the separation of water-soluble vitamins.

The chromatographic behavior of some nucleosides, pyrimidines and purines on a new p-tert-butyl-calix[8]arene-bonded silica gel stationary phase (CABS) were studied by high performance liquid chromatography. Their retention behavior on CABS were compared with those on ODS. The influence of mobile phase variables, such as methanol content, pH and ionic strength on the retention behavior were studied. Some nucleosides, pyrimidines and purines on CABS were successfully separated. The results show that the calix[8]arene-bonded phase exhibits high selectivities for the above analytes in high aqueous mobile phases. According to the chromatographic data, it is indicated that hydrophobic interaction, hydrogen-bonding interaction, and dipole–dipole interaction are mainly responsible for the retention behavior. In addition, in some extent, the vertical stacking action of the analytes on CABS can also change the retention behavior. CABS was superior to ODS in the routine fast separation of nucleosides and bases.

The photolytic and photocatalytic degradation of p-chlorobenzoic acid (p-CBA) in aqueous solution were investigated using two kinds of low-pressure mercury lamps: one emitted at 254 nm and the other emitted at 254 nm and 185 nm. Both the photolytic and photocatalytic degradations of p-CBA followed pseudo first-order reaction rate form. The rate constants decreased with increase of initial concentration in VUV and TiO2/VUV. The TiO2/VUV was the most efficient process, in which rate constants was 3.0–6.5 times as that in TiO2/UV depending on the initial concentration. The gas bubbling efficiently improved the mass transfer and the kind of bubbling gas had evident influence on the reaction rate except in UV photolysis. TOC reduction rate was greatly reduced in VUV and TiO2/VUV processes when bubbled with nitrogen gas, it was no more than one third of that when bubbled with oxygen, however, the degradation rate of p-CBA was not affected by bubbled nitrogen so greatly.

The photocatalytic activity of the carbon-black-modified nano-TiO 2 (CB-TiO 2 ) thin films was 1.5 times higher than that of TiO 2 thin films in degrading Reactive Brilliant Red X-3B. Photocatalytic oxidation and ozonation of catechol over CB-TiO 2 thin films supported on Al sheet was investigated. The experiments showed that ozone concentrations had an important effect on TOC removal. The combined photocatalysis with UV irradiation and ozonation (TiO 2 /UV/O 3 ) process considerably increased TOC removal rate compared to combined photocatalysis with UV irradiation and oxygen oxidation (TiO 2 /UV/O 2 ) process, ozonation alone (O 3 ) process, combined ozonation and UV irradiation (UV/O 3 ) process. The complete mineralization of catechol followed pseudo-zero-order kinetics dependent upon ozone (oxygen) concentration and indicated catechol concentration did not affect the kinetics during UV/O 3 and TiO 2 /UV/O 3 (O 2 ) processes. The kinetic study showed that the rate constants in the complete mineralization of catechol with TiO 2 /UV/O 3 are 1.32–1.80 times higher than that of UV/O 3 with the same concentration of ozone. The rate constants are 2.56–5.36 times higher than the maximal rate constants of TiO 2 /UV/O 2 and 4.68–9.8 times higher than the maximal rate constants of TiO 2 /UV.

A new p-tert-butyl-calix[8]arene-bonded silica gel stationary phase (CABS) was used for the separation of some aromatic carboxylic acids by HPLC. The chromatographic behaviour of the solutes on CABS was studied in comparison with conventional ODS. The results show that the calix[8]arene-bonded phase exhibits a stronger retention and better selectivity than ODS for the aromatic carboxylic acids. The different elution order of the analytes was also observed on both packings, which show the existence of distinct retention mechanisms. According to chromatographic data, it can be concluded that the high selectivity of CABS for aromatic carboxylic acids ascribes to various interactions between CABS and the analytes, such as hydrophobic interaction, hydrogen bonding interaction, pi-pi interaction and inclusion interaction.

Background MicroRNAs (miRNAs) have been documented as playing important roles in cancer development. In this study, we investigated the role of miR-124 in breast cancer and clarified the regulation of flotillin-1 (FLOT1) by miR-124. Methods The expression levels of miR-124 were examined in breast cancer cell lines and patient specimens using quantitative reverse transcription-PCR. The clinicopathological significance of the resultant data was later analyzed. Next, we explored the function of miR-124 to determine its potential roles on cancer cell growth and migration in vitro. A luciferase reporter assay was conducted to confirm the target gene of miR-124, and the results were validated in cell lines and patient specimens. Results We found that miR-124 expression was significantly downregulated in breast cancer cell lines and patient specimen compared with normal cell lines and paired adjacent normal tissues (P MiR-124 was also associated with tumor node metastasis (TNM) stage (P = 0.0007) and lymph node metastasis (P = 0.0004). In breast cancer cell lines, the ectopic expression of miR-124 inhibited cell growth and migration in vitro. Moreover, we identified the FLOT1 gene as a novel direct target of miR-124, and miR-124 ectopic expression significantly inhibited FLOT1. Luciferase assays confirmed that miR-124 could directly bind to the 3′ untranslated region of FLOT1 and suppress translation. Moreover, FLOT1 was widely upregulated, and inversely correlated with miR-124 in breast cancer tissues. Consistent with the effect of miR-124, the knockdown of FLOT1 significantly inhibited breast cancer cell growth and migration. We also observed that the rescue expression of FLOT1 partially restored the effects of miR-124. Conclusions Our study demonstrated that miR-124 might be a tumor suppressor in breast cancer via the regulation of FLOT1. This microRNA could serve as a potential diagnostic marker and therapeutic target for breast cancer.

β-CD-mono-6-(N-aminoethyl)-3-aminopropyltrimethoxy silane was synthesized and used together with 1,2-bis(triethoxysilyl)-ethane(BTEE) as silica resources templated by cetyltriethyl-ammnonium bromide(CTAB) for preparing mesoporous chiral materials via hydrothermal processes.After phenylcarbamated with phenyl isocyanate an organo-inorganic chiral silica composite(β-CD PMOs) was obtained,in which β-CD was incorporated to the wall of the channels while ethyl groups were located in the framework.The periodic mesporous organosilicas(PMOs) was utilized as chiral stationary phase(CSP) for enantioseparartion of some alkaline medicines containing nitrogen under reverse-phase high-performance liquid chromatography(RP-HPLC) and normal-phase high-performance liquid chromatography(NP-HPLC) conditions.The results showed that the enantioseparartion of these medicines could be effectively achieved by β-CD PMOs using common mobile phases at the similar pH value(pH=4.15).The maximal enantioseparartion selectivity factor(α) was 2.42.In addition,excellent permeability and reproducibility facilitate the establishment of a new enantioseparation method for chiral medicines.The chromatographic data indicated that β-CD PMOs are promising for the enantioseparation of medicines.

The synthesized and purified cucurbit[7]uril(CB[7]) was coated on a 102 white celite carrier under acidic conditions as a new gas chromatography(GC) stationary phase.The chemical structure of the CB[7] was characterized by infrared spectroscopy,mass spectrometry,elemental analysis and thermogravity analysis.The McReynolds constants of the new stationary phases were determined by using different probes in order to characterize its basic chromatographic property.The separation abilities of some aromatic hydrocarbons,halohydrocarbons,alcohols,ketones,esters,siloxanes were investigated on the packed column of CB[7] coated stationary phase,respectively.The results showed that new CB[7] stationary phase exhibited not only a good thermal stability and also a better separation selectivity for different analytes,indicating that the CB[7] stationary phase has a great potential in GC separations.Especially,some high boiling point esters and siloxanes can be successfully separated within 7 min.Additionally,the retention mechanism of the CB[7] stationary phase was also discussed.

A series of bismuth oxyhalides with controllable composition and band structure have been successfully synthesized by a facile and general one-pot hydrothermal route using Bi2O3 as the starting material; their band structures and visible-light-induced photocatalytic performances are investigated.

We announce with satisfaction that combined treatment on 70 inpatients who suffered esophageal cancer in its middle or late course is perfectly successful. The combined methods include phototherapy, microwave therapy, and anticarcinogen local injection. The results are as follows: CR 3 cases, holds 4.3% of the total inpatients; PR 36 cases, 51.4%; MR 24 cases, 34.3%; NR 7 cases, 10%; the total effective rate 90%. Splendid results of treatment on enlarging the canal, improving dysphagia, and releasing obstruction have been obtained. The dysphagic grade increased from 66 to 148, the grade of esophagostenosis from 64 to 147, and the obstruction releasing rate is 69 out of 70 (that is 98.6%). The histological observation after treatment shows that 59/62 inpatients being reported as having cancer cells appear to have retrogression accompanied with a few or large quantities of necrotic cancer cells, and 3 inpatients were changed to negative reaction. No obvious poisoning or side effects arose. The combined treatment is more advantageous on those of old age or the physically weak and those who cannot stand for an operation, radiotherapy, or normal chemotherapy.

Nanoporous SnO2 containing two types of porous structures has been prepared at the air–water interface by a new photochemical route. This room temperature method is surfactant- and template-free, low-cost, and high-yield. Only SnSO4 and diluted H2SO4 aqueous solution were used as precursors. Under ultraviolet (UV) light irradiation, Sn2+ absorbs photons to produce metallic tin and stannic ions. The metallic tin reacts immediately with oxygen in the air to form SnO2. Meanwhile, a small amount of tin can also react with H2SO4 and is dissolved in the solution to form one type of nanoporous structure. The stannic ions are converted to insoluble H2SnO3 which dehydrates to form the other type of porous SnO2 structure during the subsequent drying process. The as-prepared porous SnO2 has higher photocatalytic activity than Degussa P25 for degrading methyl orange (MO) solution under the irradation of a xenon lamp.

Cadmium-rich CdS nanotubes were directly obtained at the air–water interface by a new photochemical route. Under ultraviolet light irradiation, branch-like lamellas were first formed on the surface of the precursor solution, and then they bent into nanotubes because of the composition difference between the two sides of lamellas during photochemical reactions and sulfur–air reactions. A typical nanotube has one spherical seal and one open end. Most of the cadmium was contained in the tubes and a little was doped in the tube-walls during their formation. Such nanotubes showed higher photocatalytic activity than the corresponding pure CdS nanotubes in the photodegradation of methylene blue because of the existence metal cadmium. This route is green, template/surfactant-free, reproducible and can be extended to prepare other binary compound semiconductor nanostructures containing elements that can react either with air or another gas.