Solvent de binding of water soluble binder in powder injection moulding

The solvent debinding of water soluble binder in powder injection moulding (MIM) was investigated systematically, including the effects of solvent types, temperature and the thickness of green parts on the solvent debinding rate. After studying the debinding of a green part with a thickness of 4.26 mm, it was found that, the debinding rate of polyethylene glycol(PEG) in water and alcohol was high initially, and then decreased; however, it would increase with temperature increasing. At room temperature, the dissolution rate of PEG in water was higher than that in alcohol, but the latter would be much faster with temperature increasing because the debinding activation energy in alcohol was 51.44 kJ·mol -1 ·K -1 , much higher than 24.23 kJ·mol -1 ·K -1 in water. With a green part thickness larger than 4.26 mm, the debinding was controlled by diffusion; but with that smaller than 2.36 mm, the debinding was controlled by both dissolution and diffusion.

Biodegradability of soil water soluble organic carbon extracted from seven different soils

Water soluble organic carbon （WSOC） is considered the most mobile and reactive soil carbon source and its characterization is an important issue for soil ecology study. A biodegradability test was set up to study WSOC extracted from 7 soils differently managed. WSOC was extracted from soil with water （soil/water ratio of 1：2, W/V） for 30 min, and then tested for biodegradability by a liquid state respirometric test. Result obtained confirmed the finding that WSOC biodegradability depended on the both land use and management practice. These results suggested the biodegradability test as suitable method to characterize WSOC, and provided useful information to soil fertility.

Relationship Between Soluble Protein,Chlorophyll and ATP in Drought-Resistant Sweet Potato Under Water Stress

Some indices concerning the metabolism of substance and energy in sweet potato leaves under water stress were studied. The results showed an obvious increase in soluble protein content. Compared with control, Chl a, Chl b, total Chl contents and the ratio of Chl a to Chl b all decreased to some extent. ATP content increased in some varieties and decreased in others, but the stronger the drought resistance of the variety , the higher the ATP content. The correlation coefficient(r)of the soluble protein content, ratio of Chl a to Chl b and ATP content as a percentage of the drought-resistant sweet potato control variety are 0. 8968, - 0. 8509 and 0. 8200, respectively, P<0. 01. So these indices can be used to evaluate the drought resistance of different sweet potato varieties.

Photocatalytic Degradation of Water-Soluble Dyes by LaCoO_3

Perovskite type oxides LaCoO 3 was prepared by citrate method in granula of 20～30 nm. Using a fluorescent Hg lamp or sunlight as irradiator, the degradation experiments of various water soluble dyes were carried out in the suspension system of LaCoO 3. The results show that the perovskite type oxide LaCoO 3 has good photocatalytic activity. With the study of X ray photoelectron spectroscopy and photoacoustic spectra, its photocatalytic activity is mainly related with the factors such as the d electron structure of ion Co 3+ , Co O binding energy and adsorbed oxygen on the surface etc.

Study on the Rapid Method to Predict Longevity of Controlled Release Fertilizer Coated by Water Soluble Resin

The study discussed the rapid method to test and predict the longevity of controlled release fertilizers （CRFs） coated by water soluble resin by using the short-term leaching under higher temperature. Pure water dissolving incubation and higher temperature leaching were used to study the patterns of the nutrient release of the CRFs. The correlation analysis between the days at 25℃ and the hours at 80℃ of Trincote 1 and Trincote 2 for the same cumulative release rates were conducted. Patterns of cumulative nutrient release curve followed one factor quadratic regression equation at each given temperatures, and each of relative coefficient was bigger than 0.995. As the temperature increased, nutrients release of the CRFs increased. The longevity of resin coated CRFs were predicted by use of both the cumulative nutrients release equation at 80℃ and the regression equation of release time needed for the same cumulative release rates between 25 and 80℃. There were only 0.3-6.9% relative errors between the tested longevity and predicted one. In conclusion, the longevity of resin coated CRFs could be predicted more quickly and precisely by use of the higher temperature short-term leaching method than that of the traditional differential release rate. The longevity of resin coated CRF could be rapidly and precisely predicted in a few hours by application of the higher temperature shortterm leaching method.

Modeling the formation of soluble microbial products(SMP) in drinking water biofiltration

Both a theoretical and an empirical model were developed for predicting the formation of soluble microbial products （SMP） during drinking water biofiltration. Four pilot-scale biofilters with ceramsite as the medium were fed with different acetate loadings for the determination of SMP formation. Using numerically simulated and measured parameters, the theoretical model was developed according to the substrate and biomass balance. The results of this model matched the measured data better for higher SMP formation but did not fit well when SMP formation was lower. In order to better simulate the reality and overcome the difficulties of measuring the kinetic parameters, a simpler empirical model was also developed. In this model, SMP formation was expressed as a function of fed organic loadings and the depth of the medium, and a much better fit was obtained.

Study on Synthesis and Biological Activities of Novel Water-Soluble Metalloporphyrins

The synthesis and characterization of a series of metal porphyrins, MII(Por), {Por=dianionic of 5, 10, 15, 20-tetrakis [4-(4′-bromobutyloxy) phenyl]porphyrinato and 5, 10, 15, 20-tetrakis [4-(4′-butyloxypyridine bromide)phenyl]porphyrinato, M=Zn, Cu, Mn, Co, Ni, Ru-CO} were described. The complexes 3a-3e were prepared from the reactions of compound 2 with metal acetates in chloroform, and the treatment of 3a-3f with excess of pyridine gave corresponding complexes 4a-4f. These new compounds were identified by absorption spectroscopies,1H-NMR and elemental analyses. The results of biological activity testing for 4a-4f revealed that 4a and 4c had stronger inhibiting action on the growth metabolism ofEsche richia coli.

Effects of operational factors on soluble microbial products in a carrier anaerobic baffled reactor treating dilute wastewater

The effects of feed strength, hydraulic residence time （HRT）, and operational temperatures on soluble microbial product （SMP） production were investigated, to gain insights into the production mechanism. A carrier anaerobic baffled reactor （CABR） treating dilute wastewater was operated under a wide range of operational conditions, namely, feed strengths of 300-600 mg/L, HRTs of 9- 18 h, and temperatures of 10-28℃. Generally, SMP production increased with increasing feed strength and decreasing temperature. At high temperature （28℃）, SMP production increased with decreasing HRT. As the temperature was decreased to 18 and 10℃, the SMP production was at its peak for 12 h HRT. Therefore, temperature could be an important determinant of SMP production along with HRT. A higher SMP to soluble chemical oxygen demand （SCOD） ratio was found at high temperature and long HRT because of complete volatile fatty acid degradation. SMP accounted for 50%-75% of the SCOD in the last chamber of the CABR. As a secondary metabolite, some SMP could be consumed at lower feed strength.

PREPARATION AND PHOTOSENSITIVITY OF WATER SOLUBLE PHENOLIC RESINS CONTAINING ACRYLOYL AND QUATERNARY AMMONIUM CHLORIDE GROUPS

New water soluble and photocrosslinkable prepolymers containing acrylate and quaternary ammonium salt groups were synthesized from epoxy phenolic resin via ring-opening reaction with acrylic acid and with aqueous solution of triethylamine hydrochloride successively. The second reaction needs no phase transfer catalyst to accelerate, since the product formed can act as a phase transfer catalyst. The prepolymer obtained contains both photocrosslinkable acrylate groups and hydrophilic quaternary ammonium salt groups. Optimum conditions for these reactions were studied. The photosensitivity of the prepolymer was also investigated. The effects of different photoinitiators, different crosslinkable diluent monomers and amine accelerator on the photosensitivity of the prepolymer were compared. The photoinitiator of hydrogen abstraction type is still effective without using amine or alcohol as accelerator, because the prepolymer contains a H beside the OH groups formed in the ring-opening reactions.

Partitioning of water soluble organic carbon in three sediment size fractions:Effect of the humic substances

Water soluble organic carbon （WSOC） in sediments plays an important role in transference and transformation of aquatic pollutants. This article investigated the inherent mechanisms of how sediemnt grain size affect the partitioning coeffcient （k） of WSOC. Influences of NaOH extracted humic substances were particularly focused on. Sediments were sampled from two cross-sections of the middle Yellow River and sieved into three size fractions （〈 63 μm, 63-100 μm, and 100-300 μm）. The total concentration of WSOC in sediments （Cwsoc） and k were estimated using multiple water-sediment ratio experiments. Results showed that Cwsoc ranged from 0.012 to 0.022 mg/g, while k ranged from 0.8 to 3.9 L/kg. Correlations between the spectrum characteristics of NaOH extracted humic substances and k were analyzed. Strong positive correlations are determined between k and the aromaticity indicators of NaOH extracted humic substances in different sediment size fractions. Comparing with finer fractions （〈 63 μm）, k is higher in larger size fractions （63- 100 μm and 100-300 μm） related to higher aromaticity degree of NaOH extracted humic substances mostly. While negative relationship between k and the area ratio of fourier transform infrared spectroscopy （FT-IR） at 3400 and 1430 cm^-1 implied that the lowest k was related to the highest concentration of acidic humic groups in particles 〈 63 μm. WSOC in finer fractions （〈 63 μm） is likely to enter into pore water, which may further accelerate the transportation of aquatic contaminants from sediment to water.

Water-soluble lipopolymer delivery of N-methyl-D-aspartic acid receptor 2B siRNA relieves chronic neuropathic pain in rats

Spinal dorsal horn N-Methyl-D-aspartic acid receptor 2B （NR2B） overexpression plays an important role in the production and maintenance of neuropathic pain. Because small interfering RNA （siRNA） can inhibit NR2B expression, siRNA may provide a novel approach to treat neuropathic pain and possibly nerve injury. However, an efficient and safe vector for NR2B siRNA has not been discovered. This study shows that a water soluble lipopolymer （WSLP） comprised of low molecular weight polyethyleneimine （PEI） and cholesterol can deliver siRNA targeting NR2B for the treatment of neuropathic pain. Results show that intrathecal injection of WSLP/siRNA complexes for 3 days inhibit NR2B gene expression with reductions in mRNA and protein levels by 59% and 54%, respectively, compared with control rats （P 〈 0.01）. Injection of WSLP complexed with scrambled siRNA, or PEI with siRNA did not show this inhibitory effect. Moreover, injection of WSLP/siRNA complexes significantly relieved neuropathic pain at 3, 7, 12, and 21 days, while injection of WSLP with scrambled siRNA or PEI with siRNA did not. These results demonstrate that WSLP can efficiently deliver siRNA targeting NR2B in vivo and relieve neuropathic pain.

Effects of Different Water-soluble Fertilizers on Yield and Quality of Strawberry under Integrated Application of Water and Fertilizer

Taking Hongyan strawberry as the material and PE drip irrigation tape and fertilizer applicator as the tool of integrated application of water and fertilizer,this experiment studied the effects of six fertilizers including Batian,Jiashili,Wangdefeng,Stanley,volfertile and calcium protein on yield and quality of strawberry. The experimental results showed that different water-soluble fertilizers had different effects on the main economic traits of strawberry. For the maximum single fruit mass,the highest was volfertile treatment( 28. 72 g),followed by calcium protein treatment,and the lowest was Stanley treatment( 23. 89 g). The fruit treated with Batian,volfertile and calcium protein was hard in the texture,the fruit treated with Wangdefeng was harder,that of Stanley was softer,and that of Jiashili was soft. The strawberry fruit treated with Wangdefeng and calcium protein was sweet,the fruit treated with volfertile and Batian was sweet,that treated with Jiashili was sour and sweet,and that treated with Stanley was slightly sour. The fruit treated with calcium protein,volfertile and Batian showed strong storage resistance.Strawberry plants treated with Batian,Wangdefeng,Stanley,and calcium protein showed stronger growth,and strawberry plants showed a semi-opening pattern. The yield of strawberry treated with volfertile was highest( 17 400 kg/ha),which was significantly increased compared with other treatments,followed by that treated by Stanley( 13 140 kg/ha).

A PRELIMINARY STUDY OF THE WATER—SOLUBLE OLIGOPEPTIDES AND AMINO ACIDS OF GINSENG

γ-Amino butyric acid(GABA)and several γ-glutamyl oligopeptides were isolated and identified from water-extract of ginseng.

Overview of milling techniques for improving the solubility of poorly water-soluble drugs

Milling involves the application of mechanical energy to physically break down coarse particles to finer ones and is regarded as a“topedown”approach in the production of fine particles.Fine drug particulates are especially desired in formulations designed for parenteral,respiratory and transdermal use.Most drugs after crystallization may have to be comminuted and this physical transformation is required to various extents,often to enhance processability or solubility especially for drugs with limited aqueous solubility.The mechanisms by which milling enhances drug dissolution and solubility include alterations in the size,specific surface area and shape of the drug particles as well as millinginduced amorphization and/or structural disordering of the drug crystal(mechanochemical activation).Technology advancements in milling now enable the production of drug micro-and nano-particles on a commercial scale with relative ease.This review will provide a background on milling followed by the introduction of common milling techniques employed for the micronization and nanonization of drugs.Salient information contained in the cited examples are further extracted and summarized for ease of reference by researchers keen on employing these techniques for drug solubility and bioavailability enhancement.

Experimental verification of nanonization enhanced solubility for poorly soluble optoelectronic molecules

Solubility enhancement has been a priority to overcome poor solubility with optoelectronic molecules for solution-processable devices. This study aims to obtain experimental data on the effect of particle sizes on the solubility properties of several typical optoelectronic molecules in organic solvents, including the solubility results of 1,3-bis(9-carbazolyl)benzene(m CP), 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)ben zene(TPBi) and 2-(4-tert-butylphenyl)-5-(4-biphenyl)-1,3,4-oxadiazole(PBD) in ethanol and acetonitrile,respectively. Nanoparticles of m CP, TPBi and PBD with sizes from dozens to several hundred nanometers were prepared by solvent antisolvent precipitation method and their solubility were determined by using isothermal saturation method. The saturation solubility of nanoparticles of three kinds of optoelectronic molecules exhibited increase of 12.9%-25.7% in comparison to the same raw materials in the form of microparticles. The experimental evidence indicates that nanonization technology is a feasible way to make optoelectronic molecules dissolve in liquids with enhanced solubility.

Quantification of soluble epoxide hydrolase inhibitors in experimental and clinical samples using the nanobody-based ELISA

To ensure proper dosage of a drug,analytical quantification of it in biofluid is necessary.Liquid chromatography mass spectrometry(LC-MS)is the conventional method of choice as it permits accurate identification and quantification.However,it requires expensive instrumentation and is not appropriate for bedside use.Using soluble epoxide hydrolase(sEH)inhibitors(EC5026 and TPPU)as examples,we report development of a nanobody-based enzyme-linked immunosorbent assay(ELISA)for such small molecules and its use to accurately quantify the drug chemicals in human samples.Under optimized conditions,two nanobody-based ELISAs were successfully established for EC5026 and TPPU with low limits of detection of 0.085 ng/mL and 0.31 ng/mL,respectively,and two order of magnitude linear ranges with high precision and accuracy.The assay was designed to detect parent and two biologically active metabolites in the investigation of a new drug candidate EC5026.In addition,the ELISAs displayed excellent correlation with LC-MS analysis and evaluation of inhibitory potency.The results indicate that nanobody-based ELISA methods can efficiently analyze drug like compounds.These methods could be easily implemented by the bedside,in the field in remote areas or in veterinary practice.This work illustrates that nanobody based assays offer alternative and supplementary analytical tools to mass spectrometry for monitoring small molecule medicines during clinical development and therapy.Attributes of nanobody based pharmaceutical assays are discussed.

Application of ion chromatography to the determination of water-soluble inorganic and organic ions in atmospheric aerosols

A simple, sensitive and convenient ion chromatography(IC) method was established for the simultaneous determination of twelve water-soluble inorganic anions(F -, Cl -, NO - 2, NO - 3, SO 2- 3, SO 2- 4, PO 3- 4), and fifteen water-soluble organic ions(formate, acetate, MSA, oxalate, malonate, succinate, phthalates, etc.) in atmospheric aerosols. The linear concentrations ranged from 0.005 μg/m 3 to 500 μg/m 3(r = 0.999—0.9999). The relative standard deviation(RSD) were 0.43%—2.00% and the detection limits were from 2.7 ng/m 3 to 88 ng/m 3. The proposed method was successfully applied to the simultaneous determination of those inorganic ions and organic ions in PM 2.5 of Beijing.

Carbamazepine solubility enhancement in tandem with swellable polymer osmotic pump tablet: A promising approach for extended delivery of poorly water-soluble drugs

Elementary osmotic pump(EOP)is a unique extended release(ER)drug delivery system based on the principle of osmosis.It has the ability to minimize the amount of the drug,accumulation and fluctuation in drug level during chronic uses.Carbamazepine(CBZ),a poorly water-soluble antiepileptic drug,has serious side effects on overdoses and chronic uses.The aim of the present study was to design a new EOP tablet of CBZ containing a solubility enhancers and swellable polymer to reduce its side effects and enhance the patient compliance.Firstly,a combination of solubilizing carriers was selected to improve the dissolution of the slightly soluble drug.Then,designing the new EOP tablet and investigating the effect of different variables of core and coat formulations on drug release behavior by single parameter optimization and by Taguchi orthogonal design with analysis of variance(ANOVA),respectively.The results showed that CBZ solubility was successfully enhanced by a minimum amount of combined polyvinyl pyrrolidone(PVP K30)and sodium lauryl sulfate(SLS).The plasticizer amount and molecular weight(MW)together with the osmotic agent amount directly affect the release rate whereas the swellable polymer amount and viscosity together with the semi-permeable membrane(SPM)thickness inversely influence the release rate.In addition,the tendency of following zero order kinetics was mainly affected by the coat components rather than those of the core.Further,orifice size does not have any significant effect on the release behavior within the range of 0.1 mm to 0.8 mm.In this study we report the successful formulation of CBZ-EOP tablets,which were similar to the marketed product Tegretol CR 200 and able to satisfy the USP criterion limits and to deliver about 80%of CBZ at a rate of approximately zero order for up to 12 h.

Improvement of humidity resistance of water soluble core by precipitation method

Water soluble core has been widely used in manufacturing complex metal components with hollow configurations or internal channels;however,the soluble core can absorb water easily from the air at room temperature.To improve the humidity resistance of the water soluble core and optimize the process parameters applied in manufacturing of the water soluble core,a precipitation method and a two-level-three-full factorial central composite design were used,respectively.The properties of the cores treated by the precipitation method were compared with that without any treatment.Through a systematical study by means of both an environmental scanning electron microscope(ESEM) and an energy dispersive X-ray(EDX) analyzer,the results indicate that the hygroscopicity can be reduced by 20% and the obtained optimal process conditions for three critical control factors affecting the hygroscopicity are 0.2 g·mL-1 calcium chloride concentration,4% water concentration and 0 min ignition time.The porous surface coated by calcium chloride and the high humidity resistance products generated in the precipitation reaction between calcium chloride and potassium carbonate may contribute to the lower hygroscopicity.

Water soluble components of PM_(10) in Chongqing, China

The concentrations of water soluble ions (Na++, NH++-4, K++, Mg+{2+}, Ca+{2+}, NO+--3, Cl+-, and SO+{2-}-4) in PM-{10} samples collected on cellulose filters by a medium-volume cascade impactor were determined, which were obtained from three kinds of areas in Chongqing: industrial area (Jiulongpo district), commercial and residential area (Jiangbei district) and background area (Jinyun Mountain in the Beibei district). The results showed that except for the background site, the annual average values of PM-{10} are 23%-61% higher than the national air quality standard (GradeⅡ) ({0.1} mg/m+3), even that the value of the control site is still 20% higher than American standard ({0.05} mg/m+3). This implied that serious pollution of fine particles occurred in Chongqing. Nine kinds of soluble ions in water of PM-{10} were analyzed by ion chromatography (IC) and the annual average concentrations follow the order of >>>, and >>>>. Their values were different in these areas: the industrial area>the commercial and living area>the control area. As for NH++-4, K++, Ca+{2+}, NO+--3 and SO+{2-}-4, their seasonal average concentrations show a similar variation trend: the values in spring and fall were higher than those in summer and winter. The seasonal average concentrations of , , and are much lower than those of other ions. However, the concentrations of changed more greatly in different seasons than those of the other three ions. Correlation coefficients showed that the three areas have been polluted by coal smoke and dust to different extents, while some local resources of pollution should be taken into consideration as well.