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An identifiable model based on near-infrared spectra (NIR) was proposed to distinguish the classification of greengrocery seeds. The performance of five pretreatment methods: Original, Smoothing, MSC (Multiplication scatter correction), SNV (Standard Normalized Variable) and FD (First Derivative) were utilized to reduce the noise in the original spectrum. The effective wavelengths were selected to remove the redundancy existing in the spectra by simulating stepwise regression. The performances of the model were optimized by the combination of pretreatments and effective wavelengths selection in this paper. Compared with the five pretreatment methods, SNV was superior to other methods with an accuracy of 100%. It is concluded that SNV coupled with simulating stepwise regression could be used to identify greengrocery seeds effectively.

The flame atomic absorption method was applied to determine aluminum in jellyfish. The optimum detecting conditions were determined through many experiments. It established a nitric oxide-acetylene flame atomic absorption method to detect aluminum content in jellyfish that a good linear relationship is obtained in concentration range and correlation coefficient r2=0.9996. There are no significant differences in results after jellyfish samples were digested by three pretreatment methods. The detection limit of this method is 3.5 mg/L, the relative standard deviations are less than 5%, and the recovery is in the range of 88.50~104.20%. The test shows that: both the precision and accuracy accord with the demands, so this instrument analytical method could apply to research on quantitative detection of aluminum in jellyfish.

This paper studied effect of different pretreatment process on Yunnan phosphorus building gypsum strength and crystal morphology such as washing method, lime neutralization method, flotation method and Hans method. A lots experiment result indicated that basic properties of phosphorus building gypsum of different pretreatment methods could satisfy related building materials products technology requirements. While inorganic impurities could be effectively removed by lime neutralization method and washing method, as well as organics could be better removed by flotation method, however, compared with other methods, the Hans method possessed the best effect about removing soluble phosphorus, fluorine and organic compounds in phosphogypsum , and had other benefit such as low cost, easy operated and high strength.

Salt lakes with large reserves of mineral resources are widely distributed in China. In addition to aboundant inorganic substances, there also exist a mass of organic compounds in the brine. It is realized these organic compounds can produce serious negative effects on the process equipment and products quality. In this work, the decolorization and COD removal of the brine by ozonation were investigated in a bubble column reactor. The effects of contact time, ozone-air flow rate, pH and temperature on the decolorization and COD removal were investigated. It was found that the decolorization and COD removal rates increased with increasing ozone-air flow rate and contact time, while increased first and then decreased with increasing temperature and pH. Under the optimal conditions, color removal reached 47.3% and COD was reduced by 42.2%. Thus, ozonation can be used as the pretreatment method for decolorization and COD removal of the brine.

Four different bacteriostatic agents H2O2, NaClO, ClO2, and ozone water (O3) were used to the sterilization pretreatment of fresh muscle ofpenaeus vannamei. The bactericidal effect of these bacteriostatic agents were evaluated by aerobic bacterial count method, sensory evaluation and chromatic aberration analysis. The results showed that the optimum pretreatment concentrations of sterilization pretreatment by H2O2, NaClO, ClO2and ozone water (O3) were 3.0 g/kg, 50 mg/kg, 150 mg/kg and 1.0 mg/kg respectively. The optimum pretreatment time of sterilization pretreatment by H2O2, NaClO, ClO2and ozone water (O3) were 60 s, 300 s, 300 s and 300 s respectively. Furthermore, the bactericidal coefficients of sterilization pretreatment by H2O2, NaClO, ClO2and ozone water (O3) were 91.6%, 95.1%, 92.3% and 99.6% respectively. The effects of color and flavor of fresh muscle treated by these four bacteriostatic agents were compared. The results showed that the color and flavor of fresh muscle was less effected by ozone water (O3) method used for sterilization pretreatment method than other three methods. The total number of bacterial colony of sample treated 600 s by 1.0 mg/kg of ozone water (O3) method was reduced to 3.4 lgCFU/g, and the advantages of this method are significant sterilization effect as well as the low influences of color and sensory quality.

Three oxidant decontaminants, including NaClO, H2O2 and an organic peroxyl acid, were introduced to destroy the cyanide ion. The residual cyanide ion concentrations in different decontamination water were detected by a cyanide ion selective meter. Before the detection process, the oxidants left in the cyanide decontamination water were pretreated by adding a certain amount of Na2SO3. Results showed that starch-iodide solution indicator method presented a perfect function on determining the dosage of Na2SO3. Values of the relative mean deviations on residual cyanide detection were below 5%. After the decontamination water was deoxidized by Na2SO3, whether the sample distillated or not could not affect the value of CN- quite much. Non-distillation was confirmed alternative in the detection of cyanide ion decontamination water. Too much standing time would lead to a relatively lower CN- concentration, especially in that of non-distillation.

According to the coordinates of the particled graph, the paper presents a secondary pretreatment method which is invariant to translation, scaling and rotation. Having the advantages of efficient and accurate, the new method is significant to image processing. As the core of the pretreatment, orientation pretreatment is described in detail. In combination with the semi-structured data storage model, the new pretreatment method can help to achieve image content retrieval and data mining of a deeper level.

This paper provides a pretreatment method for ore leaching solution by adding an agent level of hydrogen peroxide. Pretreatment temperature, agent level of hydrogen peroxide and pretreatment time were investigated. The results show that relative standard deviation of copper or iron in ore leaching solution determined by iodometry is less than 1.00% with good accuracy and precision under the following conditions: pretreatment temperature of 60°C, agent level of hydrogen peroxide 1.0mL, pretreatment time of 30 minutes. This pretreatment process is simpler, faster, easier to control, and less environmental pollution comparing with the traditional pretreatment.

onic liquid, 1-n-butyl-3-methylimidazolium chloride ([C4mi Cl) was used to pretreat sugarcane bagasse (SCB), followed by regeneration of SCB by addition of deionized water. The regenerated SCB exhibited enhancement in enzymatic saccharification with an average 3.1-fold enhancement in yield of reducing sugar produced compared to untreated SCB in the kinetic study. The maximum yield of glucose and reducing sugar produced were 2.6% and 4.3% respectively for untreated SCB, whereas the maximum yield of glucose and reducing sugar produced were more significant with value of 7.2% and 16.6% respectively for IL-pretreated SCB. This paper suggested that the IL-pretreatment of SCB could be a useful pretreatment method to increase the yield of sugars produced in enzymatic saccharification.

As lignocellulosic biomass, the cornstalk should be pretreated before anaerobic fermentation for hydrogen production. In this study, HCl, NaOH and enzyme were employed for cornstalk pretreatment and the products were used for anaerobic biohydrogen production. Hydrogen yield and hydrogen production rate were investigated to optimize cornstalk pretreatment method. In addition, the economic effect and energy consumption were also considered to evaluate the pretreatment methods. The optimum cornstalk pretreatment method was soaking in 2% NaOH at 50°C for 48h with a hydrogen yield of 55.0 ml/g-TS and a hydrogen production rate of 6.5 ml/h/g-VS in anaerobic hydrogen production.

Large amounts of waste clay brick generated in the city expansion process, which formed serious harm on the city environment, and resulted in the waste to the aggregate resources. The waste clay brick was processed the recycled aggregate, which can be used for preparing the recycled concrete. The pretreatment method to recycled aggregate have certain influence on the compressive strength of recycled concrete, through the experiment, we can get that different pretreatment methods can improve accordingly the compressive strength of recycled concrete, and has certain reference significance to the reuse of recycled aggregate.

In this research the atomic absorption spectroscopy method (the correlation coefficient was 0.9995) was employed for determination of the content of heavy metal-manganese in panax pseudo-ginseng var. notoginseng, which was chosen as the sample. The optimum conditions of two pretreatments were researched independently. In the dry ashing, the optimized temperature and time are 600°C and 4~6 hours respectively, and the manganese content determined is 53.16 ug/g and the recovery rate of manganese added in sample is 98.64%. In the wet digestion, The HNO3-H2O2 digestion system is the best one, and the content was 52.95ug/g and the recovery rate is 97.30%. So the two pretreatment methods of the sample are accurate enough on manganese content determination. But the dry ashing is better than the wet digestion relatively.

Sewage sludge (SS) contains deleterious constituents that strongly inhibited seed germination. Pretreatment methods of composting, leaching and carbonizing were thus evaluated to alleviate the phytotoxicity. All the pretreatments improved germination rate, root length and germination index of radish seeds. The best performances were presented by composting pretreatment and the pretreatment of carbonizing plus leaching. Composting greatly alleviated phytotoxicity of SS and improved seed germination, however, it also showed stunted root length and germination index compared with the soil control. The adverse effects of composted SS on seed germination were completely eliminated by leaching, while carbonizing had little effect on reversing the stunt. These results indicated that the most effective pretreatment method to alleviate phytotoxicity of SS were composting plus leaching.

Recently, some solid state fermentation (SSF) processes of xanthan production were studied. However, quantitative analysis of the concentration of xanthan and biomass is more complicated than that of submerged fermentation. To facilitate the analysis of these components, near–infrared spectroscopy (NIRS) was used. A NIRS calibration models for rapidly estimating xanthan and biomass concentration in xanthan fermentation on inert support of polyurethane foam was established. The wavenumber and spectral pretreatment method were optimized. The data of cross validation and external validation shows that NIRS was suitable for rapid and accurate quantification of the concentration of xanthan and biomass in solid state fermentation on inert support. This method will provide much convenience for the research of solid state fermentation on inert support.

In order to increase the extraction rate of flavonoids from mungbean skin, twin-screw extrusion process was used as a pretreatment method. After optimizing conditions of twin-screw extrusion process, effects on ethanol extracting flavonoids were studied. Results revealed that the best extrusion conditions were: screw speed at 268r/min, extrusion temperature at 115~120°C, feed moisture at 17% and feeding rate at 726g/min. Under these conditions, the optimum condition for ethanol extraction of flavonoids was: using 38% ethanol solution at a material-liquid ratio of 1:20 at 77.5 °C with 2.5 h. The average extraction rate of flavonoids from mungbean skin was 3.14%, comparing to rate of un-extruded material 2.07%, extraction rate raised by 51.5%. This pretreatment can destroy the density structure of mungbean skin which has great effect on the increase of extraction rate of flavonoids.

The biosorption of neutral red, from aqueous solutions by Penicilium sp. biomass was studied in a batch system with respect to pretreatment methods, contact time, pH, initial dye concentration and temperature. The NaHCO3- treated biomass exhibited maximum dye uptake at pH 5-6. A larger amount of dye was removed by the pretreated biomass in the first 10 min of contact time and the equilibrium was established in 60 min for 50 mg/L of initial dye concentration. The optimum biosorption temperature was determined as 40 °C. Biosorption played main role in dye removal from aqueous solution in this study. The results indicate that the pretreated Penicilium sp. biomass can be used as an effective biosorbent to remove neutral red from aqueous solution.

Bamboo fiber reinforced polylactic acid composite is a kind of green composite materials with excellent performance, which is environmental safe and degradable in natural environment. Literature regarding the characteristics of reinforcement and matrix, pretreatment methods, preparation technology and biodegradable nature of the bamboo/ polylactic acid composite was reviewed and a particular bamoo/ polylactic acid composite made by biaxial weft knitted fabrics was developed. The composite demonstrated excellent tensile and flexural performance. In addition, the influence of the linear density of the binder yarns on the mechanical properties of this composite was insignificant.

A kind of method with immune ant colony algorithm (IACA) was applied for ship parts nesting problems. Graphics coding and pretreatment method of ship parts were proposed. A method of combination and filling transformed ship parts nesting problem into orthogonal rectangular nesting problem. An automatic nesting system was realized by use of remaining rectangular matching method and orthogonal approach grafting algorithm. A specific example was given according to the proposed algorithm, the nesting results prove that it is feasible for ship parts optimization nesting problem with IACA.

A steam pretreatment method with low severity and post pretreatment with alkaline peroxide were investigated in this study with respect to the factors affecting delignification efficiency of Lespedeza Stalks. In alkaline peroxide procedure, four factors were compared to evaluate the lignin removal: substrate concentration (w/w), the ratio of peroxide to substrate (w/w), temperature and time. The remaining lignin of fractions from Lespedeza stalks steam pretreated at low severity was apparently reduced by post treatment with 1 g H2O2/g substrate at the substrate concentration of 1.67% under 60°C for 72h. Scanning electron microscopy images show that the samples with alkaline peroxide treatment have the smoother surface because of the elimination of lignin droplets and the fiber bundles individualized.

Taking Cu(CH3COO)2·H2O and activated carbon (AC) which was treated by acid and alkali as raw materials. The polylol reduction method was then adopted to prepare the cuprous oxide and activated carbon composite material. The structure and morphology of composite material samples were characterized by BET, SEM and XRD. The effects of cuprous oxide and activated carbon composite material on reducing the hazards of hydrocyanic acid in the cigarette were studied. Different pretreatment methods and the effect of mixture ratio to drop focal relieving harm of hydrocyanic acid in the cigarette were examined.

Wheat straw is one of the most abundant and cheap lignocellulosic waste materials in the world. Nowadays, field burning is the major practice for removing wheat straw due to lack of effective utilization, but it increases the air pollution and consequently affects public health. Wheat straw is an attractive lignocellulosic raw material for binderless particleboard production. In this study, steam explosion was adopted as pretreatment method for wheat straw. The pretreated wheat straw was used to produce binderless particleboard panels. The influence of both pretreatment temperature and residence time on chemical composition of wheat straw, and modulus of rupture, internal bond and water absorption of panel boards was investigated. The results showed that defiberation of wheat straw raw material occurred during steam explosion pretreatment. The modulus of rupture and internal bond increased while water absorption of panels decreased as pretreatment severity increased. The optimum pretreatment condition, with 19.8 MPa of modulus of rupture, 0.2572 MPa internal bond and 61.5% of water absorption of panels, occurred under 170°C temperature and 10 minute residence time.

Influence of different pretreatment methods applied on anaerobic mixed inoculum was evaluated for selectively enriching the hydrogen (H2) producing mixed culture using glucose as substrate. The cumulative H2 yield and H2 production rate were found to be dependent on the type of pretreatment procedure adopted on the parent inoculum. They could be increased by appropriate pretreatment methods, including use of heat, alkaline or acidic conditions. Along with the processing temperature and time of heat pretreatment and alkaline of alkali pretreatment increasing, the H2 yield increased and then declined, but it declined and then increased as the acidity of acid pretreatment increasing. Among the studied pretreatment methods, the heat pretreatment methods procedure enabled higher H2 yield and the maximum H2 production rate, then were alkali and acid pretreatment methods. When the inoculum was heat-treated at 80°C for 30 min, the highest cumulative H2 yield was obtained at 2152.0 mL, which was 53.20% higher than the control, and the maximum H2 production rate was 178.0 mL h-1, which was 122.0% higher than that of the Ctrl (138.0mL h-1).

The main objective of this paper was to investigate a low cost pretreatment method, namely microwave-assisted extraction(MAE) pretreatment, which could be applied to hemp degumming with low environmental impact. Degumming index, contrast of different pretreatment methods, transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), and single fiber tensile testing were used to characterise the effect of pretreatment on hemp fibers. In this paper, the results of degumming effect were given comparing MAE pretreatment with acid pretreatment for hemp degumming. It was found that the MAE pretreatment could remove non-cellulosic compounds from hemp bundles effectively with very short period of time. Meanwhile, seen from SEM micrographs, the fibers pretreated by MAE were cleaner than that of fibers pretreated by acid. These results suggested that MAE pretreatment was higher efficiency and more environmental friendly than traditional pretreatment methods.

As methods of preparation, many technical such as degradation of lignocellulose materials, organic synthesis, the reinforcement of composites et al. have been introduced into self-bonding technology. According to different treatment, pretreatment methods have been divided into three categories: Physical method, chemical method and biological method. According to different mechanisms, each method is further classified. The types and action mechanism of pretreatment were summarized. Physical pretreatment usually have various degrees impact on the bonding strength but weak controllability, while chemical pretreatment have obvious effect on the bonding strength increased but serious pollution. Biological pretreatment is a promising but immature technology. By comparing the advantages and disadvantages of different methods, Feasibility of combined application of different methods is analyzed. Finally, the development foreground of pretreatment techniques in self-bonding composites is predicted based on the current research.

To achieve high value-added utilization, vinasse was chosen as raw material for l-lactic acid production. Alkali methods, microwave were used to treat vinasse and the optimum parameters during the process were investigated. The results showed that the best pretreatment way was the combination of alkali concentration of 8% and microwave power 700W, corresponding maximum lactic acid concentration was 17.5g/L, higher than those of the independent method utilized, the fermentation time could be one day earlier than other methods. The conversion rate of preprocessed vinasse to L-lactic acid and utilization rate of cellulose and hemi-cellulose could reach 23.8% and 71%, respectively. The optimized pretreatment could effectively realize hydrolysis of vinasse and make it an ideal sources for further utilization.

The research on biomass conversion technology has attracted great attention of the world along with the shortage of fossil energy resources. But the effect and efficiency of the pretreatment technique now used in biomass conversion are not so perfect. Using new steam explosion technique as a pretreatment process of biomass conversion has been reported rarely. The mechanism of steam explosion and its application effect in biomass conversion and utilization were introduced and analyzed respectively in this paper. The result showed that the semi-cellulose of steam exploded corn stalk degraded greatly to 7.57% from 25.4%, and a little cellulose and lignin degraded in this process. The saccharification rate of steam exploded green reserved corn stalk was 33.4% under the condition 2.0Mpa, 120s. It’s 1.33 times higher than the unexploded. According to the result of experimentation, the steam explosion technique should be a good pretreatment method for biomass conversion.

The modification method and its eftect on the behavior of sepiolite, especially its ability to remove heavy metals, have be reaen systematically studied. Different pretreatment methods have led to various surface structures, which resulted in various effects on removal heavy metals. The processes of modification and removal of heavy metals have been optimized. The highest removal rate for Pb canch more than 96%.