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The present research work presents the study of cost effective cellulose fibers as sorbent for the U(VI) removal from nuclear wastewaters. Alkali-treated cellulose fibers (ATCFs) were extracted from alkaline peroxide mechanical pulp board by using CH3COOH and NaOH treatment. Sorption capability was ascertained by conducting batch experiments. The kinetic sorption of U(VI) on ATCFs could be described by the pseudo-second-order rate equation well. The results demonstrated that the sorption of U(VI) to ATCFs was strongly dependent of pH and weakly dependent of ionic strength. U(VI) sorption on ATCFs was mainly dominated by the outer-sphere complexation.

To reduce the refining energy consumption of chemi-mechanical pulping, treatment with NaOH-thiourea-urea aqueous solution was studied in this work. By means of single-factor experiments, the effects of alkali dosage, soaking time, and freezing time were evaluated. It was found that the optimal conditions were an alkali dosage of 8%, soaking time of 45 min, and freezing time of 105 min. The results revealed that refining energy consumption could be reduced by approximately 40% under optimal conditions compared with that of alkaline peroxide mechanical pulp, while other pulping or paper-making properties were similar. There were no significant effects on the structure of the functional groups, the crystalline region of the pulp, or the whole structure of the treated wood chips. However, damage to single wood fibers on the chips treated in NaOH-thiourea-urea aqueous solution was more obvious.

Lignocellulosic biomass has great potential as a low-cost source of fermentable sugar for the production of biofuels and high value organic acids. One potential biomass is oil palm empty fruit bunch, since it has high cellulose and hemicellulose content. However, its lignin content can hinder the access of cellulose and hemicellulose during the hydrolysis process. Therefore, an effective pretreatment for the delignification of lignocellulose biomass should be considered to reduce the lignin content. In this study, delignification of oil palm empty fruit bunch using peracetic acid and alkaline peroxide solution combined with the ultrasound method is investigated as a novel combination method of biomass pretreatment. The effect of pretreatment time was observed by using a peracetic acid solution for 1, 3, 5, 7 and 9 hours, followed by an alkaline peroxide solution for 4, 6, 8 and 10 hours. Based on the results, the best delignification was achieved by pretreatment using peracetic acid pretreatment for 3 hours, followed by alkaline peroxide pretreatment for 10 hours. Both pretreatments were assisted by the ultrasound method. The results show hemicellulose, cellulose and lignin content of 14.13%, 77.27% and 8.6% respectively. The lignin content was reduced by 68.73% and the cellulose content increased by 121.85%, relative to the untreated EFB. This result was considered as the best pretreatment, since the pretreatment time was shorter and high cellulose content together with low lignin content was achieved, which will improve the hydrolysis process.

Objective: To investigate the effect of alkaline peroxide-type denture cleanser agents on the microbial profle, namely Streptococcus , Staphylococcus , and Candida species, in maxillary complete dentures. Methods: A total of 20 patients with maxillary complete dentures were recruited. Three denture cleanser agents were selected ( n = 5): Polident ® (P); Steradent ® (S); and Pearlie White ® (PW), with distilled water (DW) as control. Dentures were brushed before immersion with denture cleansers. Denture bioflm was collected from the palatal impression surface of the denture before and after immersion. The collected microorganisms were cultured and colony forming units (CFU) were counted. Results: Signifcant reduction in the numbers of Streptococcus an Staphylococcus was observed after immersion with all denture cleanser agents ( p 0.05). Furthermore, S was more effective among other cleansers compared to DW ( p < 0.05). Conclusion: Immersion of dentures in denture cleansers can reduce the amount of microorganisms on denture surfaces; thus, leading to effective denture hygiene. Steradent ® denture cleanser showed the highest percentage reduction of polymicrobial organisms.

The pyrolysis behaviors of the three major organic components of eucalyptus alkaline peroxide mechanical pulping (APMP) spent liquor including alkali lignin (AL), lignin-carbohydrate complexes (LCC), and polysaccharide (PLS) were studied with emphasis on the effect and contributions of components on the overall pyrolysates of APMP spent liquor solid (ASLS). Profound differences on product properties from each component pyrolysis were illustrated. The results indicated that the bio-oil during ASLS pyrolysis was mainly attributed to AL, while the bio-gas and char were mostly affected by PLS. Small molecule hydrocarbons released during ASLS pyrolysis mainly came from AL and LCC, and CO and CO2 mainly produced from PLS. As for bio-oils, AL generated the largest proportion of monomeric phenols and aromatic hydrocarbons (AHs), while PLS and LCC mainly contributed to the production of ketones, furans and acids. The correlation shown here is of interest for further studies on pulping spent liquor grading utilization.

Lignocellulose materials, essentially consisting of lignin, cellulose and hemicelluloses, are abundant sources of fermentable sugars. The bast fiber of Crotalaria juncea (Sunn hemp), a native cover crop of India, was used as feedstock for this study. The primary objective of this study was to add value to the waste C. juncea bast fiber. The same was achieved by pretreating the waste fiber using alkaline peroxide solution at various process conditions. The optimal process condition for alkaline peroxide pretreatment was identified for the fiber to pretreatment solution (S/S) ratio of 1/40 at 50°C for 5h with respect to all response variables (lignin removal, hemicellulose recovery, recovery of solid pretreated material, and crystallinity of lignocellulose). Three-way ANOVA results revealed that S/S ratio had no significant effect; whereas, both temperature and time, and the combination of parameters, exhibited significant effect on response variables. The characteristic peaks associated with lignin and cellulose demonstrated a higher amount of lignin removal and increased cellulose content with elevated treatment time. Autoclave assisted pretreatment proved to be inefficient due to removal of lower amount of lignin in addition to higher hemicellulose degradation. On the other hand, pretreatment using ultrasound was found to be most effective in removing lignin, liberating hemicelluloses along with diminition in cellulose crystallinity.

Four fiber fractions from poplar alkaline peroxide mechanical pulping, performed with refiner-chemical preconditioning (P-RC APMP), were used to estimate inter-fiber bonding capacity. The relationship between fiber characteristics and inter-fiber bonding capacities was investigated. The surface lignin content of the long fiber fraction was slightly lower than that of the short fiber fraction. Atomic force microscopy (AFM) images showed that the fiber surfaces were heterogeneous (i.e., different cell wall layers were exposed along the fiber surface). The fiber fractions that had lower surface lignin content had higher bonding capacities. Furthermore, modified PFI beating was used to peel the surface of the fibers. After the peeling treatment, the fiber surface charge increased remarkably, while the surface lignin concentration decreased considerably. The lignin and charge on the fiber surface are the two key factors for estimating the inter-fiber bonding capacities.

Fall leaves are biodegraded and composted naturally in forests but they are wastes for urban areas. Moreover, they are widely available cellulose sources but have limited applications. Alkaline peroxide treatment of bioresources is one of the most widely studied clean methods for both delignification and hemicellulose removal but there is no study about application of that method on fall leaves at room temperature. In this study, the effect of alkaline peroxide treatment of fall leaves at room temperature on hemicellulose recovery and cellulose delignification were investigated. Fall leaves (FL) were treated with 0.3-3.0 M NaOH + 0-3 M H2O2 at room temperature. Hemicellulose recovery and cellulose delignification values were analyzed. Hemicellulose recovery and cellulose delignification increased and yield decreased by increasing NaOH and H2O2 concentrations. Hemicellulose recovery and cellulose delignification reached to the maximum levels, 99.5% and 81.6% respectively, at 3M NaOH + 3M H2O2 treatment condition. The end products were confirmed by analytically, spectrally and morphologically. Wasted fall leaves were turned into useful hemicellulose and cellulose products by using clean alkaline peroxide treatment at room temperature. The products can be further processed by known methods into other industrial products.

Chemiluminescent acridinium dimethylphenyl esters are highly sensitive labels that are widely used in automated assays for clinical diagnostics. Light emission from these labels and their conjugates is triggered by treatment with alkaline peroxide. In the current study, we provide a comprehensive examination of how polarity of the N-alkyl group in acridinium dimethylphenyl esters and their protein conjugates affect their properties. We describe a new synthetic strategy for the manipulation of the N-sulfopropyl group in acridinium esters which facilitates the attachment a structurally simple sulfobetaine zwitterion to the acridinium nitrogen. Our studies are the first and most detailed to date and they indicate that N-alkyl groups containing charge-neutral sulfobetaines in acridinium dimethylphenyl esters as exemplified by the labels 3 and 6 offer significant advantages over commonly used N-sulfopropyl groups. These include faster emission kinetics, improved chemiluminescence stability and lower non-specific binding to magnetic microparticles with different surfaces. Acridinium ester 3 is a particularly attractive new label because it contains a structurally simple N-alkyl group with a sulfobetaine zwitterion and its synthesis is relatively straightforward from the corresponding N-(3-chloropropyl) substituted acridinium ester precursor.

Effects of four different kinds of industrial grade MgO as one alkali source in the alkaline peroxide bleaching of poplar chemi-thermomechanical pulp (CTMP) were investigated. The particle size and activity of the MgO played the most important role in the improvement of optical and strength properties of the bleached CTMP. At a 25% substitution percentage of MgO for NaOH, a 77.4% ISO brightness and the optimal tensile index of the bleached CTMP could be obtained. When industrial grade MgO was applied, appropriate increase in Na 2 SiO 3 dosage and pulp consistency could improve the brightness and strength properties of the bleached CTMP.

Pretreatment of biomass is expected to improve the pulp properties and facilitate the main components in the raw materials to be better used. In this work, the refining energy consumption and properties of the poplar chemithermomechanical pulp (CTMP) from different autohydrolysis pretreatment intensities of wood chips were investigated, and the pulp bleaching ability was also studied. The results showed that the CTMP with autohydrolysis pretreatment at a severity factor of 3.47 could have a 26% energy reduction in pressurized refining, a 60% energy saving in PFI refining, and 44% and 46% increases in tensile and tear indices, respectively. Autohydrolysis pretreatment prior to pulping could result in CTMP with a higher water retention value, higher fines content, better strength properties, lower shives content, and lower bulk and ISO brightness after PFI refining. The brightness of CTMP can be improved by alkaline peroxide bleaching.

Aerobic activated sludge was more appropriate for APMP(Alkaline Peroxide Mechanical Pulp) effluent treatment than anaerobic processes because the high content of toxic wood extractives in the effluent. In this article, Eucalyptus APMP effluent was treated with activated sludge and the process conditions was optimized. The optimized conditions were: the initial pH value was 6.0, SV30of activated sludge was 35%, and loading volume of flask was 150ml (250ml flask), cultured shakily for 3 days at 35°Cand 150rpm. The removal of COD was 66.75%, from 4181mg/l to 1390mg/l, and the color of the effluent and treated water were 2541C.U. and 1557C.U. under the optimized conditions, respectively. In most cases, the color of treated wastewater was increased compared with the initial effluent, but the removal of COD was significant.

In recent years, the alkaline peroxide mechanical pulping performed with refiner-chemical preconditioning (P-RC APMP) has obtained a wide application in many paper grades in China. This is due to such desirable pulp characteristics as its high bulk, opacity, and light scattering coefficient. However, compared with its bleached chemical pulps, the poplar P-RC APMP has weak bonding strength, which limits its application in value-added products. Usually, the interfiber bonding abilities of different fiber fractions are quite different. In this study, the page bonding strength index (B) and the interfiber bonding abilities (shear bond strength per unit area (b) and relative bonding area (RBA)) of different P-RC APMP fiber fractions were extrapolated by the traditional Page Equation. The results show that the higher B could be obtained when the fiber fraction was shorter or smaller. The same trend was observed for b and RBA. Wet pressing was used to improve the bonding ability, and higher pressure of wet pressing or shorter fiber fraction can lead to obviously higher tensile strength.

To improve ethanol productivity with few inhibitors generated, a novel process of combined alkaline peroxide (AP) pretreatment and semi-simultaneous saccharification and fermentation (SSSF) was developed in this work. Pretreatment with 10% (g H2O2/g wood) H2O2 at 160°C for 2h followed by SSSF was found to be the optimal combination with remarkably increased ethanol yield. The proposed process resulted in 63.1% of ethanol yield, which was about five times more than that of the untreated sample that was processed using conventional simultaneous saccharification and fermentation (SSF). The efficient conversion was ascribed to the high delignification efficiency (64.9%) of AP pretreatment, which led to incompact structure and generation of fewer inhibitors during SSSF (c. 6g/L of lactic acid) than SSF (c. 10 g/L of lactic acid). This combined approach was proved to be an effective method for the promotion of the bioconversion of lignocellulosic materials.

Background To evaluate the effect of denture cleansers with and without fatigue stress on the retention of the locator attachments. Materials and methods Three dummy implants of length (13 mm) and a diameter of 4.2 mm with their locator abutments were embedded into three acrylic resin blocks. Seventy pink locator attachments were divided into three groups: 10 for group I, 30 for each group II and group III. Group I exposed to 600 cycles of insertion and removal equivalent to 6 months use, group II and group III was subdivided into three subgroups, A, B, C according to the type of cleaner which was soaked in water, chlorhexidine gluconate 2% and alkaline peroxide solution for a period equivalent to 6 months. Group III was soaked in water, chlorhexidine gluconate 2% and alkaline peroxide solution, then exposed to 600 cycles of insertion and removal. The pink locator was tested for load to dislodgment on universal testing machine with a load cell of 5 kN at a crosshead speed of two in/min. Retention of locator attachments were statistically analyzed using Mann–Whitney test. Difference of mean values between more than two groups was tested by Friedman χ2-test. Results Group I: The retention of pink locator attachments was significantly decreased after 600 cycles of insertion and removal P = 0.005. Group II: The retentive value for attachment soaked in chlorhexidine gluconate 2% and that soaked in alkaline peroxide solution was significantly lower than that soaked in water (P = 0.001). Group III: the locator soaked in water and chlorhexidine gluconate 2% and alkaline peroxide solution was significantly affected after 600 cycles of insertion and removal. Conclusion Chlorhexidine gluconate 2% and alkaline peroxide solution has significant decrease the retention of pink locator attachment. Fatigue has significant effect on the retention of locator attachment either with or without the use of denture cleansers.

The chemical compositions of cotton stalk and bast are similar to those of hardwood and superior to those of grass fiber. With respect to the morphological characteristics of their fibers, cotton stalk is similar to hardwood and cotton bast is similar to softwood. The average length of cotton bast fibers is nearly triple that of cotton stalk fibers, and the length-to-width ratio is almost quadruple. Traditionally, cotton stalk and cotton bast are pulped together, which affects the quality and homogeneity of the pulp and complicates bleaching, limiting its use to low-grade paper. In this study, cotton bast and cotton stalk were separated and pulped individually by alkaline peroxide extrusion pulping (APEP). The orthogonal analytical method was used to determine the optimal pulping parameters. Compared to those obtained via the kraft pulp (KP) of cotton stalk as a whole, far superior yield and whiteness were obtained in APEP. Further, with APEP, lower amounts of chemicals and less energy were consumed and there was little pollution. The physical performance of APEP was slightly lower than that of KP. With respect to bast alone, the physical performance of APEP was almost as good as that of KP.

The layer-by-layer deposition technique was adopted in this paper to improve the physical strength properties of alkaline peroxide mechanical pulp (APMP). The cationic starch (CS), anionic polyacryamide (APAM) and cationic polyacryamide (CPAM) were chosen and used to build-up polyelectrolyte multilayers on surface of APMP fibers. The improvements of physical strength of pulp through adsorption of different polyelectrolyte onto fibers were discussed and compared. The results showed that when the APMP fibers were treated with CPAM, the breaking length and burst index were 53% and 83% respectively, higher than that of untreated pulp. The optimal treatment conditions are 60 mgCPAM/g pulp, 1.5% pulp concentration and 9min treatment time. The pulp deposited by CPAM-APAM polyelectrolyte multilayer gave a highest physical strength compared with pulp with other multilayer deposition such as CS-APAM. At the whole beating degree range investigated in this paper, the CPAM-APAM deposition on fiber surface can improve the physical strength properties significantly, especially when the beating degree is at 40oSR. In addition, the improvement of physical strength can be remained even after pulp refining.

To convert bleached softwood paper grade pulp into dissolving pulp for viscose application, two stages of treatments consisting of enzymatic treatment and alkaline peroxide treatment were investigated. It was found that high reactivity (about 80%) of pulp could be achieved by endoglucanases (EG)-rich industrial cellulase treatment, and the alpha-cellulose content as well as the viscosity of enzymatically treated pulp can be further adjusted by the alkaline peroxide treatment with certain dosages of NaOH and H2O2 to finally meet the quality requirements of dissolving pulp. The resulting pulp with 68.7% of reactivity, 92.1% of alpha-cellulose content, and 506.9 mL/g of pulp viscosity could be obtained after the two stages of treatments. The appropriate dosage of EG-rich cellulase was 300 IU/g bone dry pulp in the stage of enzymatic treatment, while the suitable dosages of NaOH and H2O2 were 9 wt% and 1 wt%, respectively, in the stage of alkaline peroxide treatment. (C) 2013 Elsevier B.V. All rights reserved.

Oxalic acid (OA), formed as an oxidation product in alkaline peroxide bleaching (P) of mechanical pulps, can form a sparingly soluble salt with calcium and cause severe scale deposit problems. The focus of this work was the question how much OA is formed from the different components of spruce (Picea abies (L.) Karst.), i.e., from cellulose, lignin, hemicelluloses, extractives, and bark, during the P-stage of bleaching. Isolated wood components and monosaccharides typical for spruce hemicelluloses and pectins were treated with chemicals of P-stage for 90 min at 73°C, and the released OA was analyzed by ion chromatography. Most OA was formed from galacturonic and glucuronic acids, xylans, and lignin. Taking into account the content of these substances in spruce wood, lignin can be regarded as the major source of oxalate. Untreated spruce bark was found to contain substantial amounts of oxalate, and an additional amount of oxalate was formed in the P-stage. It is evident that effective debarking is essential, not only for pulp brightness, but also for the control of calcium oxalate formation.

Objective: To evaluate the effects of one denture cleanser on the surface roughness of heat-cured and cold-cured acrylic resin materials. Materials and Methods: Two acrylic resin materials (one heat cured and one cold cured) were used in this study. Twenty disk-shaped specimens (10 mm in diameter and 2 mm thick) were prepared from each resin, polished, and stored in water at 37°C for 48 hours. Disinfection methods included immersion in an alkaline peroxide effervescent denture cleanser for 5 minutes and then immersion in water at 37°C. The disinfection procedures were repeated 60 times in 6 days before submitting the specimens to surface roughness measurements. Control specimens (not disinfected) were kept in distilled water at 37°C for 6 days before undergoing surface roughness tests. Statistical analyses of data were conducted with an ANOVA and a Tukey post hoc test (α=0.05). Results: Cold-cured acrylic resin test specimens showed significantly (p

Treatment of the abundant oil palm empty fruit bunches with alkaline peroxide chemicals and subsequent fibrillation at varying mechanical energies resulted in favourable morphological changes of the generated fibers. The produced fibrous mass composed of intensely fibrillated elements ranging from micro to nanodiameter fibrils. nanofibrils and webs of nanofibrils were factors contributing to the functionality of the fibrous mass as fibre web augmentation elements. Profound improvement in fiber network is particularly attributable to the ability of the collected elements to fill up inter-fiber gaps and this was attributable to the micro elements in the form of micro fines, segmented micro-fibrils and webs of nanofibrils. The uniquely generated thin layers of nanofibril webs (TN-webs), were found to increase fiber web density by gluing multiple layers of fibers, together. Having landed on the surface of micro-fiber web, these TN-webs were identified as responsible for the masking effects of the underlying micro-fibres. Under such condition, fibers were observed to coalesce, suggesting also an augmented fiber network as evident from the 130% increase in tensile index and a 450% enhancement in burst index of the resultant fiber web relative to those formed with the basic alkaline peroxide chemical-mechanical refining (CMR) synergy. This reveals a great promise to EFB for application as super-strong fibre-web materials such as packaging and specialty paper-based products.

Pulp from the oil palm empty fruit bunches (EFB) was extracted via Alkaline Peroxide Pulping (APP). The pulping process was conducted through three main steps; dewaxing of EFB, impregnation of alkaline peroxide (AP) into EFB and refining of biomass to finally produce the pulp. The varying peroxide levels and number of impregnation stages were found to affect the refining energy consumption and the properties of the resultant pulp and paper. Diagnosis by electron microscopic imaging revealed a strong correlation between paper properties development and paper surface morphologies. By multiplying the stages of the low alkaline peroxide level (2:2.5% AP) impregnation, refining energy could be reduced by 30% while improving brightness and paper mechanical properties. Higher alkaline peroxide level (4:5% AP) could reduce the refining energy by 50% while still improving brightness. Beyond these AP levels (8:10% AP), refining energy could be reduced by 67% by increasing the number of impregnation stages, with positive effects on brightness and paper mechanical properties. The findings suggest that increasing the AP impregnation stages had exposed more active sites to react with AP. The enhanced AP accessibility to EFB structures facilitated mechanical fibrillation of EFB vascular bundles through the refining process. The proper synergy between AP and the adopted mechanical refining was the factor that triggered the liberation of nanocells from EFB biomass and this had ultimately improved paper properties.

The increasing popularity of the oil palm empty fruit bunches (EFB) as a source of non-wood fibre has prompted a variety of research on processing and utilisation of the material. In an attempt to define the characters, reusability and end-of-life, oil palm EFB was processed by the alkaline peroxide variable treatment (APVT) systems. Low synergy between alkaline peroxide (AP) chemical and mechanical fibrillation through fibrillation (CMR synergy) revealed the yield of segments of EFB vascular bundles while heightening the mechanical forces further, generated more uniform but a mixture of fiber and segments of fibre bundles. An intermediate CMR synergy generated fibres forming a more well-defined but a rough resultant fibre network due to partial fibrillation of the vascular bundle. Applying maximal CMR synergy was found to generate higher yield of network strengthening fibrous cells. These were later identified as nanoscale fiber network or nanoscan, consisting of 10-80 nm diameter fibers arranging themselves in a systematic network. Analysis of the polarity of fibers harvested from the APVT systems manifests the systematic construction of nanofibrils winding in helical manner to form arrays of nanofibres that glue themselves together as micro-fibrils. Interconnections between fibers and other gluing elements led to the vascular bundle known as the EFB biomass that was once dross and that can now be marvelled as an alternative source of nanofibers for the nanoindustry sector.

Fiber morphology, chemical composition and wood characteristic of fast-growing black poplar branch were studied. Meanwhile, pulping performance of it used for alkaline peroxide mechanical pulp (APMP) was discussed preliminarily. The research results showed that the fast-growing black poplar branch can be used as raw materials for APMP pulping and papermaking.

In this paper the two-stage method of enzyme-mild acidic hydrolysis was adopted to isolate lignin from the APMP(Alkaline Peroxide Mechanical Pulp),then the isolated lignin was treated with a laccase-mediator system(LMS).The phosphor magnetic resonance spectrum (31P-NMR) measurements and Infrared spectral analysis technology were chosen to analyze the structural changes of LMS-treated APMP residual lignin.

This paper compared the differences of laccase modified APMP and unmodified controlled trails to characterize laccase’s impacts on the whiteness, physical properties and fiber morphology of APMP. From this paper, we can see that after laccase modified, the whiteness of the APMP significantly reduced; physical properties of the APMP were reduced after the first enhanced with increasing the amount of laccase. when the amount of laccase was 2u/g, the physical properties of the APMP were best, the same time after 2u/g laccase treatment ,the surfaces of the pulp fibers engendered the devillicate and peeling.

In this paper, the poplar Alkaline Peroxide Mechanical Pulp (APMP) pulping wastewater was treated by the SBR. The pulping wastewater was from the processes of washing, soaking and defibrination. The COD of the pulping wastewater was 5671 mg/L and the BOD was 1862 mg/L. The B/C (biological oxygen demand/chemical oxygen demand) ratio of the pulping wastewater was 0.32, which indicated that the wastewater was suitable to be treated by biological methods. SBR technology was used to treat the pulping wastewater. After a series of experiments, the best conditions for the pulping wastewater was achieved as follows: time 6hrs, original pH about 8. Under these conditions the removal ratio of COD can reach 81.4% and that of BOD can reach 91.5%;but the removal ratio of the TSS and the Chromaticity were low, the removal ratio of TSS only reach 31.8%.

The study is aiming at the finding of optimal pulping conditions for the alkaline peroxide mechanical pulping process applied to larch in terms of brightness (% ISO) and tensile strength (TS). Based on three variables, the Box-Behnken experimental design was applied to determine the effects of the first-stage and second-stage dosages of H2O2 and the impregnation temperature on % ISO and TS. The equations based on the quadratic regression analysis were developed, which describe the response behaviors as the simultaneous functions of the selected independent variables. The best brightness achieved was 75.4% ISO under the following conditions: first-stage H2O2 3.5%, second-stage H2O2 3.54%, and impregnation temperature 81.4°C. The best TS (37.2 N·m g-1) was found under the following conditions: first-stage H2O2 2.4%, second-stage H2O2 3.9%, and impregnation temperature 90°C.

High-yield pulp (HYP) has various fractions, and they not only play an important role in the papermaking process but also affect paper properties. Hence, it is necessary to clarify the impact of different HYP fractions on paper formation and properties. In this study, the characteristics of poplar preconditioning followed by refining chemical treatment alkaline peroxide mechanical pulp fractions were determined, and their effects on paper formation and paper properties were investigated. The results show that the HYP fiber is not as flexible as the bleached wheat straw pulp fiber. Compared with the HYP long-fiber fraction, the short-fiber fraction can improve the formation index more favorably. It was also found that the long-fiber fraction can maintain the strength properties, while having a negligible effect on the light-scattering coefficient; on the contrary, the short-fiber fraction can improve the light-scattering coefficient effectively but reduces the strength properties.

Preconditioning Refiner Chemic Alkaline Peroxide Mechanical Pulp (PRC-APMP) is one of the most currently used high yield pulps in China. During the bleaching of PRC-APMP, hydrogen peroxide is a commonly used bleaching agent. In order to improve the bleaching efficiency of PRC-APMP, urea was used as an activator in peroxide bleaching of aspen PRC-APMP. The results showed that the brightness of the urea-based bleached pulp higher than that without urea addition at the same hydrogen peroxide dosage. The physical properties such as the breaking length, tear index and fiber length of the bleached pulp were comparable to those without urea addition in peroxide bleaching.

In the mechanical pulping process, some process state and product quality variables are difficult to measure on-line. In this paper, soft sensors were used to estimate Canadian Standard Freeness (CSF) and outlet consistency (Cout) after the high consistency refining stage of the alkaline peroxide mechanical pulping (APMP) process. After the secondary variables for modeling that are readily available processed measurements in pre-treatment and the HC refining stage was selected, models based on the case-based reasoning (CBR) method were developed to estimate CSF and Cout. The ability of CBR soft sensors to predict CSF and Cout was tested using data collected from an APMP mill, and the results were satisfactory. Additionally, two typical soft sensor methods that back propagation network (BP) algorithms and support vector regression algorithms (SVR) were employed to predict CSF and Cout and evaluate the performance of the CBR soft sensor. As a result, the proposed soft sensor demonstrated a better performance than the BP method and can be regarded as of comparable quality to the SVR method.

Amaç: Bu çalışmanın amacı; protez temizleyici solüsyonların ısı ile polimerize olan akrilik rezinin mikrosertliği üzerine etkisini incelemektir. Gereç ve Yöntem: 50 akrilik rezinörnek (15 mm × 15 mm × 3 mm) hazırlandı. Örnekler rastgele dağıtılarak,sıralanan solüsyonlara göre gruplara ayrıldı:% 0.2 klorheksidin glukonat, %0.5 sodyum hipoklorit (NaOCl), %1 NaOCl,alkalin peroksit tablet solüsyonu (n=10). Kontrol grubu örnekler distile sudabekletildi. Solüsyonlarda bir daldırma 20-dakika olarak belirlendi. Her birörneğin Vickers sertlik değeri mikrosertlik cihazı ile daldırma öncesi ve 720daldırma sonrası ölçülerek karşılaştırıldı.Veriler SPSS 15.0 programına taşınarak eşleştirilmiş örneklemler t-testi,tek yönlü varyans analizi ve Tukey HSD testi ile gruplar arası karşılaştırmalaryapıldı (p< 0.05).Bulgular: Bulgular alkalin peroksit tablet solüsyonunun akrilik rezinin mikrosertliğinde istatistiksel olarak anlamlı azalmaya yol açtığını göstermiştir. Çalışmada test edilen diğer solüsyonlar akrilik rezinin mikrosertliği üzerinde anlamlı bir etkiye neden olmamıştır. Sonuç: Alkalin peroksit tablet solüsyonu hariç distile su, %0.2 klorheksidin glukonat, % 0.5 NaOCl ve %1 NaOCl solüsyonları günde 20 dakika kullanımı taklit eden 720 kullanım periyodunda ısı ile polimerize olan akrilik rezinin mikrosertliğini anlamlı olarak etkilememiştir Anahtar kelimeler: Diş protezi, Protez temizleyicileri, Sağlamlık testleri, Akrilik rezinler EFFECT OF DENTURE CLEANSING SOLUTIONS ON MICROHARDNESS OF A HEAT-CURE ACRYLIC RESINAim:The aim of this study was to investigate the influence of denture cleansing solutions on micro hardness of a heat-cure acrylic resin.Materials and Methods: Fifty specimens (15mm × 15 mm × 3 mm) were prepared with a heat-cure acrylic resin. Specimens wererandomly distributed into groups and immersed in the following solutions: 0.5%sodium hypochlorite (NaOCl), 1% NaOCl, alkaline peroxide tablet solution and,0.2% chlorhexidine gluconate. The control group was immersed in distilledwater. An immersion was detected 20-minute for all solutions. The microhardnessvalue of each specimen was obtained using the microhardness testing machinerecording the Vickers hardness number before the beginning of the immersioncycles and after completion of 720 immersion cycles and compared. Data wereimported to SPSS 15.0 software and were analyzed by paired t-test and One-WayANOVA and Tukey HSD test were used for comparison among groups (p< 0.05).Results: The results show that alkaline peroxide tablet solution caused the statistically significant reduction of the microhardness of the acrylic resin. Other solutions tested in this study did not cause a significant effect on the microhardness of the acrylic resin.Conclusions:It was concluded that immersion in distilled water, chlorhexidine gluconate, 0.5% NaOCl and, 1% NaOCl solutions, simulating 720 days of 20 min daily soaking did not cause clinically significant adverse effects on the microhardness of the heat-polymerized acrylic resin, except for the alkaline peroxide tablet solutions.Keywords: Dental Prostheses, Denture Cleansers,Hardness Tests, Acrylic Resins

In this chapter the literature on the alkaline hydrogen peroxide (AHP) pretreatment of biomass is reviewed. The review focuses on parameters that influence the efficiency of biomass decomposition aimed at further production of biofuels. The optimal process conditions of the AHP method are discussed. Many examples are given for the application of this pretreatment method to various kinds of biomass. The mechanism of delignification by the AHP treatment is discussed, and the newest proposal for the process kinetics is given. The direction of further investigations of the AHP pretreatment are suggested.

Aiming at resolving the large difficulty of gap adjustment in APMP (Alkaline Peroxide Mechanical Pulp) refiner, and it is difficult to reach the production requirement by using traditional PID controller, an improved PID controller (human-simulation intelligent PID controller) is proposed through combining the conventional PID controller and human-simulation controller. And it has been used in APMP refiner control, and the simulation results and practical application results show that this method is feasible and accurate.

The origin and kinetic changes of carboxyl groups in aspen chemithermomechanical pulp (CTMP) fibres during alkaline peroxide bleaching were evaluated. The results showed that the major contributors of carboxyl groups in aspen CTMP fibres were the 4-O-methylglucuronic acid, galacturonic acid and the carboxyl groups in oxidized lignin. Alkaline peroxide bleaching could increase the total carboxyl groups, surface charge and dissolved anionic substances. However, the excess degradation by superfluous hydroxide and peroxide could result in the reduction of carboxyl groups in fibres because of the production and dissolution of low-molar-mass substances. The total carboxyl groups from polysaccharides in fibres remained constant, and the increase of carboxyl groups in fibres should result from the carboxyl groups newly formed by the lignin oxidation during peroxide bleaching. Alkaline peroxide bleaching could also result in the removal of a large part of extractives and a small fraction of lignin on the fibre surface.

Xylan, galactoglucomannan, arabinogalactan and hemicelluloses with different molecular weights were prepared from wood and then used as wet-end additives and surface sizing agents in papermaking. The results showed that xylan, galactoglucomannan and arabinogalactan all had obvious paper-strengthening effect. As wet-end additives, galactoglucomannan had the best effects, followed by xylan and then arabinogalactan. As surface sizing agents coordinating with starch, xylan showed the best sizing effect (paper-strengthening effect and water resistance), followed by galactoglucomannan. The effects were both greater than that of starch alone. Furthermore, hemicelluloses with higher molecular weights had more significant effects. The results could provide some reference for the use of hemicelluloses in nature and papermaking waste liquor to improve paper physical strength. Although hemicelluloses in APMP (alkaline peroxide mechanical pulp) waste liquor was degraded to a certain degree, it also showed good paper-strengthening effects. Starch as an important papermaking additives comes mainly from food. The hemicelluloses, especially in the high-yield-pulp waste-liquor, can replace starch in papermaking to some extent, which might be beneficial from economic, energy and food standpoints.

Paper properties, including physical properties and optical properties, fiber quality analysis and COD in the pulp effluent were used to investigate the effects of substituting Mg (OH)2 for NaOH on the properties of poplar APMP in this paper. The results from fiber quality analysis showed that increasing the substitution levels of Mg (OH)2 for NaOH in the poplar APMP could increase the content of fiber fines,the pulp had shorter average length,and levels of kinking and curl reduced.The results of paper properties analysis ,including physical properties and optical properties ,showed that the bulk and light scattering coefficient of handsheets could be improved,while the physical strength and brightness couled be decreased after using Mg (OH)2.The research for COD in the pulp effluent showed that it could reduce content of COD in the pulp effluent after substituting Mg (OH)2 for NaOH on the properties of poplar APMP,so that clean production can come true easierly,while it could retrench the cost of production and yield good economic returns.

In this study, the structural modification of Siam weed (Chromolaena odorata) was performed using NaOH–H2O2- and Ca(OH)2–H2O2-based oxidative pretreatment for the enzymatic conversion of the biomass to a biocommodity, reducing sugar (RS). Pretreatment of raw sample was evaluated at temperatures of 60°C, 70°C, 80°C, 90°C for different time intervals of 3, 6, 9, 12 h in alkaline medium (NaOH or Ca(OH)2). The effects of pretreatment time and temperature were considered in obtaining the optimum conditions. The optimum conditions for NaOH–H2O2 was obtained at 70°C and 3 h with a maximum cellulose content of 44.29%(w/w), lignin content reduced to 21.09% from the initial raw value of 24.2%. Pretreatment with Ca(OH)2–H2O2 resulted in the optimum conditions obtained to be 70°C for 3 h with a cellulose content of 47.18%. Enzymatic hydrolysis on the pretreated biomass at the optimum conditions showed NaOH–H2O2-treated sample yielded 424.35 mg equivalent glucose/g biomass of RS while Ca(OH)2–H2O2-treated sample yielded 335.81 mg equivalent glucose/g biomass of RS. The untreated raw sample yielded 68.75 mg equivalent glucose/g biomass of RS. Consequently, NaOH–H2O2 pretreatment displayed a higher efficiency than Ca(OH)2–H2O2 pretreatment. Stereomicroscopic and scanning electron microscopic imaging of the treated and untreated samples revealed morphological disruptions brought about by the treatments.

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.

Comparisons were studied for untreated and pretreated bagasse with dilute alkaline peroxide and steam for bioethanol production by simultaneous saccharification and fermentation (SSF) process in a continuous stirred batch bioreactor using fungi Fusarium oxysporum. The optimum parameters for bioethanol fermentation were: time, 48 h; pH, 6.0; temperature, 50°C; stirring speed, 35 rpm; and bagasse loading, 35 g/L. Maximum concentrations of bioethanol at optimum fermentation process parameters were 18.73 g/L, 19.69 g/L and 20.45 g/L for untreated, steam and dilute alkaline peroxide pretreated bagasse, respectively. Maximum yields of bioethanol were 0.706 g/g, 0.734 g/g and 0.764 g/g of bagasse at optimum parameters for untreated, steam and dilute alkaline peroxide pretreated bagasse, respectively. The sp. growth rate (µ) of fungi Fusarium oxysporum was determined at 5.91 s−1, 6.25 s−1 and 7.11 s−1 and maximum sp. growth rate (µmax) was calculated at 11.81 s−1, 12.50 s−1 and 14.22 s−1 for untreated, s...

This study evaluated the long-term efficacy of denture cleansers against Candida spp. biofilm recolonization on liner surface. Specimens were fabricated of a poly(methyl methacrylate)-based denture liner and had their surface roughness evaluated at baseline and after cleansing treatments. C. albicans or C. glabrata biofilms were formed on liner surface for 48 h, and then the specimens were randomly assigned to one of cleaning treatments: two alkaline peroxides (soaking for 3 or 15 min), 0.5% sodium hypochlorite (10 min) or distilled water (control; 15 min). After the treatments, the specimens were sonicated to disrupt the biofilm, and residual cells were counted (cell/mL). Long-term effectiveness of the cleaning processes was determined by submitting a set of cleaned specimens to biofilm growth conditions for 48 h followed by estimation of cell counts. The topography of specimens after cleaning treatments was analyzed by SEM. Data were analyzed by ANOVA and Tukey's test (α; = 0.05). Results of cell count estimation showed significant differences in cleanliness among the treatments (p < 0.001), and it could be observed by SEM. However, no significant difference (p > 0.05) was observed among the Candida species regarding the recolonization condition. Alkaline denture cleansers showed similar cleaning performance and both differed from the control (p < 0.001). Sodium hypochlorite was the only treatment that removed biofilm efficiently, since no viable cells were found after its use. In conclusion, alkaline peroxide denture cleansers were not effective in removing Candida spp. biofilm from denture liner surfaces and preventing biofilm recolonization.

Wool is commonly treated with alkaline protease enzyme to improve handle and shrink resistance. The limitations associated with the usage of this enzyme on wool are excessive weight and strength losses and pH sensitive enzyme activity, etc. Wool is generally stable if processed in acidic conditions rather than alkaline conditions. This study explores the possibility of using acid protease enzyme to improve handle and shrink resistance of wool. The acid protease enzyme is applied on acid and alkaline peroxide bleached wool fabrics using optimized process parameters, and the results are compared with alkaline protease enzyme treated wool fabric. The acid protease treated fabrics show 30% higher softness than alkaline protease treated fabrics with 72% and 62% lower weight and strength losses, respectively. The alkaline peroxide bleaching prior to acid protease treatment provides 100% and 67% higher whiteness and shrinkage resistance, respectively, to wool than the acid peroxide bleaching. The action of the e...

In the conventional preconditioning followed by refiner chemical treatment, alkaline peroxide mechanical pulping (P-RC APMP) process, sodium hydroxide (NaOH) is used as the alkali source. In this s...

Eucalyptus wood chips were subjected to impregnation with various blends of novel fiber modify-ing enzymes before chemical pretreatment and two stages of refining using the preconditioning refiner chemical–alkaline peroxide mechanical pulping (PRC-APMP) process. Wood chip impregnation and pulp processing was con-ducted at a pilot plant in the United States. When compared under constant chemical application and at a constant 350 mL CSF, enzyme treatment reduced specific refining energy by at least 24%. The effect of one versus two stages of impregnation and of enzyme action upon several physical pulp properties was determined.

Eucalyptus wood chips were impregnated with various blends of fiber modifying enzymes prior to preconditioning refiner chemical-alkaline peroxide mechanical pulp processing. The process includes chemical pretreatment and two stages of refining. The energy consumption was compared at the same Canadian standard freeness level of 350 ml. Some enzyme treatments were found to reduce specific refining energy (SRE) by at least 24%. The enzyme hydrolysis within the cell wall was observed by transmission electron microscopy of impregnated chips with high spatial resolution. The enzyme blends that successfully reduced SRE requirements were found to selectively loosen the bonds between the S1 and S2 layers of the fiber wall. Enzymes which selectively attached the S2 layer did not impart any SRE reduction. All experiments for impregnation and pulp processing were conducted at the Andritz Pilot Plant in Springfield, OH.

ÖZETAmaç: Diş protezlerinin temizliği ve dezenfeksiyonuna gereken önemin verilmemesi, ağız içi enfeksiyonlarla birlikte endokardit gibi sistemik enfeksiyonlara da yol açabilir. Bu tür enfeksiyonların önlenmesi veya azaltılabilmesi için uygun protez kaide materyalinin seçimi ile birlikte protezlerin temizlenmesi ve dezenfeksiyonunu sağlayabilen etkin bir ürünün belirlenmesi büyük önem taşımaktadır. Araştırma- mızda, halen Türkiye’de diş protezlerinin temizliği ve dezenfeksiyonlarında kullanılan çeşitli ürünlerin antibakteriyel etkinliklerinin araştırılması amaçlanmıştır.Materyal ve Metod: Araştırmamızda, 3 adet alkalen peroksit grubu efervesan diş protez temizleme tableti (Fittydent (Matilek-Avusturya), Corega tabs (GlaxoSmithKline, İrlanda), Protefix (Queisser pharma, Almanya)) ile 2 adet dezenfektan solüsyonun (Curaprox BDC 105 (haftalık kullanımlı) (Swiss Premium Oral Care, İsveç), Curaprox BDC 100 (Günlük kullanımlı) (Swiss Premium Oral Care, İsveç)); dört tip protez kaide materyali deney örneklerine (Vertex (Vertex-Dental B.V, Hollanda), Rodex (Rodont, İtalya), Meliodent (Kulzer, Almanya), Molloplast-B (Detax, Almanya)) bulaştırılmış Staphylococcus aureus ATCC 6538, Pseudomo- nas aeruginosa NCTC 6749 ve Bacillus subtilis var. niger ATCC 9372 bakteri suşlarına karşı etkinlikleri üretici firma tarafından önerilen sürelerde incelenmiştir.Bulgular: Denenen ürünlerin tamamının S.aureus ATCC 6538 bakteriye karşı; %100 oranında etkili olduğu belirlenmiştir. P.aeruginosa NCTC 6749 suşuna karşı ise; Fittydent’in, 30 dakika temas süresinde, Corega tabs ve Protefix tabletlerinin 15’er dakikada, Curaprox BDC 105’in ise, 1. ve 7.gün sonunda da 6 saatlik temas süresinde aynı etkiyi (%100) gösterdiği belirtilmiştir. Curaprox BDC 100’ün ise, 5 dakika temas süresinde % 93-100 arasında etkinlik sağladığı gözlenmiştir. B.subtilis var. niger ATCC 9372 bakteri sporu üzerinde; Curaprox BDC 105’in 1. ve 7.gündeki solüsyonla- rının %99 oranında etkili olduğu, diğer ürünlerin ise temas süre ve protez maddelerine göre Fittydent’in; %97-98, Corega tabs’ ın ; %91-99, Protefix’in; %68-95, Curaprox BDC 100’ ün; %72-99 gibi değişen oranlarda dezenfeksiyon sağladığı belirlenmiştir. Sonuç: Farklı tip diş protez kaide maddeleri üzerinde temizlik ve dezenfeksiyon ürünlerinin etkinliklerinin ortamda bulunan bakterilere göre çok değişken olduğu, protez kaide maddesi tipinin ise dezenfeksiyon üzerinde bir etkisinin olmadığı gözlenmiştir. Protezlerin her gün temizlenmesinin ve dezenfeksiyonunun potansiyel patojen bakteriyel kontaminasyonunu önlemek için etkili bir yöntem olduğu sonucuna varılmıştır.Anahtar sözcükler: Diş protezi, temizlik, dezenfeksiyonAN INVESTIGATION OF THE BACTERIOLOGICAL ACTIVITY OF DENTURE CLEANSING PRODUCTSABSTRACTAim: The unsufficient cleaning and disenfection of the dentures not only lead to intra-oral infections but also to systemic infections such as endocarditis, which might be life threatening. To prevent or reduce such infections, selection of appropriate denture base material and effective denture cleaning or disinfecting preparations are very important. In our study, we aimed to investigate the antibacterial activity of cleansing and disinfectant preparations currently use in Turkey.Material and Method: In our study, the antibacterial activity of 3 alkaline peroxide type cleaning denture effervescent tablets (Fittydent (Matilek-Austria), Corega tabs (GlaxoSmithKline, Ireland), Protefix (Queisser pharma, Germany) frequently use in our country and 2 disinfectant solutions (Curaprox BDC 105 (weekly use) (Swiss Premium Oral Care, Sweden), Curaprox BDC 100 (daily use) (Swiss Premium Oral Care, Sweden), were tested against four types of denture base material samples (Vertex (Vertex-Dental B.V, Netherlands), Rodex (Rodont, Italy), Meliodent (Kulzer, Germany), Molloplast-B (Detax, Germany)) contaminated with Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa NCTC 6749 and Bacillus subtilis var. niger ATCC 9372 at the contact times advised by the manufacturers. Result: It was determined that all of the preparations were found to be 100% effective against S.aureus ATCC 6538 strain. Fittydent at 30 minutes, Corega tabs and Protefix tablets at 15 minutes of each, and Curaprox BDC 105 at 6 hours in the solutions prepared in the 1.st and the end of the 7.th days, were have the same activity(100%) against P.aeruginosa NCTC 6749 strain.Otherwise, Curaprox BDC 100 at 5 minutes contact time was found 93-100 % effective against the same strain. The sporicidal activity of the Curaprox BDC 105 against B.subtilis var. niger ATCC 9372 at 6 hours contact times in the solutions prepared in the 1.st and the end of the 7.th days, were found to be 99%, whereas the activity of the rest of the products were varied depending on the contact time and denture base material and differed between 97-98% of Fittydent ,91-99% of Corega tabs , 68-95% of Protefix, 72-99% of Curaprox BDC 100.Conclusion: The effect of denture base materials on the cleaning and disinfection were very variable according to the kinds of bacteria present in the test environment and have not shown to be differed depending on the type of denture base material. Daily cleaning or disinfection of the dentures are an effective way to prevent bacterial contamination with potential pathogens Key words: Denture, cleaning, disinfection, Aim: The unsufficient cleaning and disenfection of the dentures not only lead to intra-oral infections but also to systemic infections such as endocarditis, which might be life threatening. To prevent or reduce such infections, selection of appropriate denture base material and effective denture cleaning or disinfecting preparations are very important. In our study, we aimed to investigate the antibacterial activity of cleansing and disinfectant preparations currently use in Turkey. Material and Method: In our study, the antibacterial activity of 3 alkaline peroxide type cleaning denture effervescent tablets (Fittydent (Matilek-Austria), Corega tabs (GlaxoSmithKline, Ireland), Protefix (Queisser pharma, Germany) frequently use in our country and 2 disinfectant solutions (Curaprox BDC 105 (weekly use) (Swiss Premium Oral Care, Sweden), Curaprox BDC 100 (daily use) (Swiss Premium Oral Care, Sweden), were tested against four types of denture base material samples (Vertex (Vertex-Dental B.V, Netherlands), Rodex (Rodont, Italy), Meliodent (Kulzer, Germany), Molloplast-B (Detax, Germany)) contaminated with Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa NCTC 6749 and Bacillus subtilis var. niger ATCC 9372 at the contact times advised by the manufacturers. Result: It was determined that all of the preparations were found to be 100% effective against S.aureus ATCC 6538 strain. Fittydent at 30 minutes, Corega tabs and Protefix tablets at 15 minutes of each, and Curaprox BDC 105 at 6 hours in the solutions prepared in the 1.st and the end of the 7.th days, were have the same activity(100%) against P.aeruginosa NCTC 6749 strain.Otherwise, Curaprox BDC 100 at 5 minutes contact time was found 93-100 % effective against the same strain. The sporicidal activity of the Curaprox BDC 105 against B.subtilis var. niger ATCC 9372 at 6 hours contact times in the solutions prepared in the 1.st and the end of the 7.th days, were found to be 99%, whereas the activity of the rest of the products were varied depending on the contact time and denture base materialand differed between 97-98% of Fittydent ,91-99% of Corega tabs , 68-95% of Protefix, 72-99% of Curaprox BDC 100. Conclusion: The effect of denture base materials on the cleaning and disinfection were very variable according to the kinds of bacteria present in the test environment and have not shown to be differed depending on the type of denture base material. Daily cleaning or disinfection of the dentures are an effective way to prevent bacterial contamination with potential pathogens

In China, alkaline peroxide mechanical pulping performed with refiner-chemical preconditioning (P-RC APMP) is well known to produce fiber with high bulk, opacity, and light scattering coefficient but weak bonding and strength properties. In this study, the characteristics of different P-RC APMP fiber fractions were investigated, and their effects on bonding strength properties were determined. The results showed that there was only 5.8% R30 fiber fraction and 14.1% P100/R200 fiber fraction, and the specific surface area increased from R30 to P100/R200. The tensile index increased by 51.85% and the bonding index increased by 15.35%, when the fibers were changed from the R30 fraction to the P100/R200 fraction. The short fiber fraction (P100/R200 fraction) had smaller fiber length and coarseness but larger specific surface area and greater surface charge density than the long fiber fraction (R30 fraction). The fiber specific surface area and surface charge density made significant contributions to the bonding capacity, whereas fiber coarseness and length were negatively correlated with the tensile index.

Vineyard pruning residues were subjected to alkaline peroxide treatment for delignification. Experimental conditions maximizing lignin removal were determined by using Box-Behnken statistical experiment design. NaOH/Biomass, H2O2/Biomass and retention time were chosen as independent variables and percent lignin removal was the objective function. Experiments were done at constant Solid/Liquid ratio of 0.1 (w/w) and 135 degrees C. All parameters were found to have significant effect on lignin removal. Complete delignification was obtained in 120 min at a NaOH/Biomass ratio of 1.10 and a H2O2/Biomass ratio of 0.65. The solid residue consisted of 95% total carbohydrate indicating significant carbohydrate enrichment after complete delignification. (C) 2015 Elsevier B.V. All rights reserved.