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In the field of soil stabilization, only calcium silicate hydrate (CSH) and ettringite (AFt) as hydration products have been reported to directly contribute to the strength enhancement of the soil. A chloride dredger fill, an artificial chloride saline soil, and a non-saline soil were stabilized by Portland cement (PC) and PC with Ca(OH)2 (CH) with different contents. A series of unconfined compressive strength (UCS) tests of stabilized soil specimen after curing for 7 d and 28 d were carried out, and the hydration products and microstructure of the specimens were observed by X-ray diffractometry (XRD), scanning electronic microscopy (SEM), and energy-dispersive X-ray analysis (EDXA). The results showed that the strengths of PC+CH-stabilized chloride saline soils were much higher than those of PC-stabilized soils. A new hydration product of calcium aluminate chloride hydrate, also known as Friedel’s salt, appeared in the PC+CH-stabilized chloride saline soils. The solid-phase volume of Friedel’s salt expanded during the formation of the hydrate; this volume filled the pores in the stabilized soil. This pore-filling effect was the most important contribution to the significantly enhanced strength of the PC+CH-stabilized chloride saline soils. On the basis of this understanding, a new optimized stabilizer was designed according to the concept that the chloride in saline soil could be utilized as a component of the stabilizer. The strength of the chloride saline soils stabilized by the optimized stabilizer was even further increased compared with that of the PC+CH-stabilized soils.

In order to simulate and study the mechanism of cement stabilized soils polluted by different contents of magnesium sulfate (MS), a series of tests were conducted on the cemented soil samples, including unconfined compression strength (UCS) tests of blocks, X-ray diffraction (XRD) phase analysis of powder samples, microstructure by scanning electronic microscopy (SEM), element composition by energy dispersive spectrometry (EDS), and pore distribution analysis by Image Processed Plus 6.0 (IPP 6.0) software. The UCS test results show that UCS of cemented soils reaches the peak value when the MS content is 4.5 g/kg. While, the UCS for Sample MS4 having the MS content of 18.0 g/kg is the lowest among all tested samples. Based on the EDS analysis results, Sample MS4 has the greater contents for the three elements, oxygen (O), magnesium (Mg) and sulfur (S), than Sample MS1. From the XRD phase analysis, C-A-S-H (3CaO·Al2O3·3CaSO4·32H2O and 3CaO·Al2O3·CaSO4·18H2O), M-A-H (MgO·Al2O3·H2O), M-S-H (MgO·SiO2·H2O), Mg(OH)2 and CaSO4 phase diffraction peaks are obviously intense due to the chemical action associated with the MS. The pore distribution analysis shows that the hydrated products change the distribution of cemented soil pores and the pores with average diameter (AD) of 2–50 μm play a key role in terms of the whole structure of cemented soil. The microscopic structure of the cemented soil with MS exhibits the intertwined and embedded characteristics between the cement and granular soils from the SEM images of cemented soils. The microstructure analysis shows that the magnesium sulfate acts as the additive, which is beneficial to the soil strength when the MS content is low (i.e., Sample MS2). However, higher MS amount involving a chemical action makes samples crystallize and expand, which is adverse to the UCS of cemented soils (i.e., Sample MS4).

A novel microporous membrane/solvent microextraction (MPMSME) approach was developed in which a piece of microporous filter membrane was used as not only extraction solvent holder but also solid phase extraction unit. Subsequently, high-performance liquid chromatography with an UV detector was conducted. The wide exchange surface and very little organic solvent consumption made this sample pretreatment technology very interesting. The cinnamic acid derivatives were used as model analytes to evaluate the procedure. Parameters that affect the MPMSME such as type of extraction solvent, membrane area (or volumes of extraction solvent), aqueous phase pH, ionic strength, extraction stirring rate, extraction time, and sample volume were investigated and optimized. The enrichment factor (EF) of analyte was defined in MPMSME. Under the optimized conditions, the EFs of cinnamic acid derivatives were 43–144. Good linearities were obtained from 4 to 4,000 ng mL−1 for all the analytes with regression coefficients of between 0.9956 and 0.9977; the limits of quantification were below 0.4 ng mL−1, and satisfactory recoveries (93–106 %) and precisions (0.37–13 %) were also achieved. The experimental results showed that the method was simple, rapid, practical, and effective for preconcentration and determination of the cinnamic acid derivatives in rhizoma typhonii.

A novel technique, ionic liquid-water-organic solvent three phase microextraction (ILWOS-3p-ME) was developed and introduced for simultaneous preconcentration and determination of flavonoids and anthraquinones in Chinese herbal formula and its preparations. This technique was performed in one step by using a syringe. High performance liquid chromatography with an UV-detector (HPLC/UV) was subsequently conducted. Two solvents with different densities (organic solvent and ionic liquid with densities less than and higher than water, respectively) were separately placed in a syringe, which was used as an extraction device. A cloudy emulsion was formed by manually shaking the syringe. The mixture was allowed to stand for several minutes; afterward, the emulsion readily separated into three phases: an upper organic solvent extraction phase; a middle aqueous sample phase; and a lower ionic liquid extraction phase. Both the upper and lower layers were transferred to a small Eppendorf (EP) tube. Conducting ILWOS-3P-ME with HPLC/UV, we simultaneously determined the bioactive components of flavonoids and anthraquinones in traditional Chinese medicine. ILWOS-3P-ME is a simple, rapid, practical, and effective method to extract and preconcentrate of different types of trace bioactive components from traditional Chinese medicine simultaneously.

The abuse and uncontrolled discharge of kanamycin may result in potential risks to human health through food chain or environmental residues. Hence, the determination of kanamycin in various matrices is necessary. A sensitive and simple dispersive liquid–liquid microextraction based on solidification of floating organic droplet (DLLME-SFO) method has been developed for monitoring kanamycin in environmental samples. The method of DLLME-SFO after derivatization is coupled with high performance LC with fluorescence detection. The comparison was carried out between the staged and one-step procedure. The results indicated that the fluorescence derivatization reaction with 9-fluorenylmethyl chloroformate should be performed prior to extraction. The derivatization and DLLME-SFO conditions were optimized, respectively. Under the optimal conditions, the proposed method presented good linearity with square correlation coefficient of 0.9934, good reproducibility with relative standard deviations less than 9.6%, and the recoveries of kanamycin ranged from 91.3 to 102.7% for wastewater, and from 90.3 to 107.7% for soil. Furthermore, the detection limit was observed as 0.012 ng/mL. The proposed method was successfully applied to determine low levels of kanamycin in wastewater and soil samples.

An advantageous method based on hollow fiber liposome microscreening (HFLMS) combined with high-performance liquid chromatography (HPLC) has been developed and used in preliminary screening and analysis of biomembrane permeable compounds from herbal medicines (HMs). In the method, a liposome hollow fiber was prepared as a screening tool; permeable compounds that could specifically bind to liposomes were screened from herbal extract to liposome in the pores and lumen of hollow fiber, then permeable compounds were dissociated from liposomes and analyzed by HPLC. The chromatographic separation was applied with a Zorbax Eclipse XDB-C18 column by a gradient elution using acetonitrile, methanol, and phosphoric acid aqueous solution as the mobile phases. In the study, influencing factors of the screened target compounds were investigated and optimized. Under optimum conditions, the surface properties of liposome hollow fibers were characterized, the nonspecific binding between the active center of hollow fiber and the bioactive components were investigated, the repeatability of this method was tested. And eight permeable compounds of flavonoids and anthraquinones from HMs were preliminarily screened and analyzed by HFLMS-HPLC. The results demonstrated that new method is a simple, fast, effective, and reliable method for preliminary screening and analyzing biomembrane permeable ingredients in HMs, and it can be used in screening other permeable compounds in HMs.

In this paper, two methods, organic solvent dispersive liquid–liquid microextraction (OS-DLLME) and ionic liquid dispersive liquid–liquid microextraction (IL-DLLME), coupled with high-performance liquid chromatography have been critically compared and introduced for the analysis of the eight coumarin compounds (psoralen, isopsoralen, bergapten, isobergapten, oxypeucedanin, imperatorin, osthole, and isoimperatorin) in Radix Angelicae Dahuricae samples. Experimental conditions have been investigated for both OS-DLLME and IL-DLLME. Under optimal conditions, the detection limits of the eight coumarin compounds obtained by OS-DLLME and IL-DLLME ranged between 0.002–0.026 ng mL−1 and 0.013–0.66 ng mL−1, respectively. The relative standard deviations (RSDs, n = 9) were lower than 8.7 and 8.4% with enrichment factors in the range of 145–380 and 130–230 folds for OS-DLLME and IL-DLLME, respectively. The results showed that there were no significant deviations between the two DLLME methods for the determination of the eight coumarin compounds. Both methods were simple, fast, efficient, and inexpensive. However, compared with IL-DLLME, the OS-DLLME technique exhibited a higher extraction capacity for the eight target analytes.

Hollow fiber liquid–liquid phase microextraction followed by high-performance liquid chromatography was employed to research the binding of four furocoumarin compounds (psoralen, oxypeucedanin, imperatorin and isoimperatorin) to bovine serum albumin. The results reveal that the percent of drug–protein binding did not rely on the furocoumarins and protein concentrations, and four furocoumarins scarcely competed for protein binding sites. The protein-binding percents of psoralen, oxypeucedanin, imperatorin and isoimperatorin were 55.1 ± 4.5, 14.4 ± 2.4, 44.1 ± 6.7, and 41.3 ± 3.8%, respectively, the numbers of binding sites were 1.2, 1.6, 0.6 and 0.3, and the binding constants were 1,801, 212, 937 and 4,025 L mol−1, respectively. The proposed new approach is simple, rapid, and effective for the study of the interaction between protein and furocoumarin compounds which is either individual or coexistent with the similar ones.

A novel hollow fiber cell fishing with high performance liquid chromatography (HFCF-HPLC) was extended and used to screen flavonoid and anthraquinone active compound groups simultaneously from traditional Chinese medicines (TCMs). In this study, three cells (MCF-7, SGC7901, and MADB-106) were seeded on the inner wall of the hollow fiber employed to screen bioactive components from TCM water decoction. The variables influencing HFCFHPLC, such as cell seeding time, screening stirring rate and time, and active compound concentration, were investigated and optimized. The surface property of the hollow fiber seeded with cells, the cell survival rate under different conditions, the nonspecific binding between active centers in the fiber and the target compounds, and the repeatability and recovery of HFCF-HPLC were analyzed and validated. Certain structures of the compounds fished by HFCF-HPLC were identified after comparing the retention times of the reference substances. To verify preliminarily the binding site between the bioactive components and cells, we separated the cell membrane and cell organelle from live MCF-7 cells. We then employed the cell membrane, cell organelle, and the whole cells to screen simultaneously the active compounds. The cell fishing factor of the active compound was calculated and discussed as the index of cell-drug binding ability in HFCFHPLC. Tamoxifen as a positive control and indomethacin as a negative control were screened by HFCF-HPLC to verify the method. The results indicate that HFCF-HPLC is an effective and reliable method for the screening and analysis of bioactive components. Moreover, this method can be applied to predict bioactive candidates in TCMs.

Hollow fibre cell fishing with high performance liquid chromatography (HFCF-HPLC) is a newly developed method used to screen and fish bioactive compounds in traditional Chinese medicines (TCMs). In the study, colorectal cancer cell HCT116 was first seeded in a hollow fibre and used for screening and fishing active compounds from TCMs. The surface properties of the hollow fibre seeded with HCT116 cells, the non-specific binding between active centres in the fibre and the target compounds, the cell survival rate under different conditions before and after screening, the repeatability and recovery of HFCF-HPLC were investigated in detail. The cell fishing factor of active compound was defined in HFCF-HPLC. We employed HFCF-HPLC to screen and fish anthraquinones active compounds group from extracts of Polygonum cuspidatum, Cecropia obtusifolia L. and Polygoni multiflori radix praeparata. Some of the anthraquinones structures screened from TCMs were identified by comparing to the retention time of the reference substances confirmed by mass spectrometry. The ability of permeable membrane of anthraquinones screened by HFCF-HPLC was further described. Indomethacin was used as the positive control substance. Results demonstrated that HFCF-HPLC is an effective, stable and reliable method to screen and analyse bioactive compounds. Other bioactive compounds from TCMs could also be screened.

In this paper, a novel hollow fiber/graphene oxide/solvent bar microextraction (HF-GO-SBME) coupled with high-performance liquid chromatography was developed and introduced for simultaneous preconcentration and determination of lipid-soluble active ingredients including dihydrotanshinone I, cryptotanshinone, tanshinone I, and tanshinone IIA, as well as water-soluble salvianolic acid B, danshensu, and protocatechuic aldehyde in Radix Salvia miltiorrhiza. To evaluate the technique, seven compounds of varying polarity were used as model analytes, and a polyvinylidene fluoride hollow fiber of 1.0 cm filled with graphene oxide attached n-octanol was used as a microextraction bar. The extraction conditions, including the amount of graphene oxide, the type and amount of organic solvent, sample phase pH, salt concentration, agitation speed, extraction time, and sample phase volume, were investigated and optimized in detail. The solid–liquid synergistic microextraction mechanism of HF-GO-SBME was analyzed and verified. Under the most favorable conditions, the enrichment factors of the target analytes were 2.4–905, the limits of detection were below 0.92 ng mL−1, and the recoveries were between 84.5% and 107.5%. Thus, HF-GO-SBME is a simple, effective, low-cost, high enhancement factor and practical microextraction mode with a wide range of potential applications for extraction and preconcentration of trace analytes.

The thermal and electrical properties of Herrin No. 6 Illinois Basin bituminous coal have been determined. The thermal conductivity and thermal diffusivity of wet and dry solid coal samples, in which the heat flow is orientated parallel and nonparallel to the bedding planes, have been determined as a function of temperature using the transient-hot-wire and transient-hot-plate methods. The data are fit to polynomials for convenient use. The electrical resistivity has been determined as a function of temperature, applied voltage and moisture content using the ASTM standard method D 257-78 and a special guarded-electrode apparatus. The dielectric breakdown strength has been determined as a function of sample moisture, sample thickness, electrode size, voltage rate-of-rise and temperature using the ASTM standard method D 149-81.