This research aimed to investigate the effect of pulping conditions and refining intensities of wheat straw to be recommended for fluff pulp production.For this purpose,mono ethanol amine(MEA)was selected as a de-lign...This research aimed to investigate the effect of pulping conditions and refining intensities of wheat straw to be recommended for fluff pulp production.For this purpose,mono ethanol amine(MEA)was selected as a de-lignification agent at three levels of 50:50,25:75,and 15:85(MEA/water,W/V%),and soda-AQ 14 W/V%was used as a reference pulping.To investigate the optimal refining intensity,the obtained pulp was passed through a single disk laboratory refiner from 0 to 6 times and in two different consistencies(1.5 and 2.5 W/V%).Total yield,kappa number,ash content,and the Schopper-Riegler(SR°)freeness of the prepared pulps were investigated.Finally,hand sheets with a targeted basic weight of 70 g/m^(2) were made according to the related standards.The hand sheets were characterized using Fourier transform infrared(FTIR)spectroscopy and a field emission scanning electron microscope(FE-SEM).Sheet density,brightness,and mechanical properties such as burst,tensile,and tear indices were also investigated.The FE-SEM photographs showed that the texture of the hand sheet became denser as the refining intensity increased.External fibrillation on the surface of the fibers was also observed,especially on those refined with 2.5%consistency.The results of the chemical composition of wheat straw indicated that wheat straw containing a high percentage of holocellulose is an excellent candidate for the production of fluff pulp.The total yield and kappa number of MEA pulps increased with the decrease in MEA concentration.FTIR results indicated the presence of a peak related to amino groups in the pulp related to MEA pulp.The results also indicated that the mechanical properties of the papers,except for the tear index,were enhanced as the intensity of refining and the pulp consistency during refining increased.展开更多
Change is the most fundamental property of a biomarker. In contrast to the blood, which is under homeostatic controls, urine reflects changes in the body earlier and is more sensitive, thus making it a better biomarke...Change is the most fundamental property of a biomarker. In contrast to the blood, which is under homeostatic controls, urine reflects changes in the body earlier and is more sensitive, thus making it a better biomarker source. Moreover, drawing blood from infants and toddlers is difficult and not tolerated well. For patients limited by language, communicating their chief complaint is difficult. Thus, monitoring biomarkers in urine can provide valuable clues for the diagnosis of diseases, especially pediatric diseases. Collecting urine from young children and some adult patients is more challenging than collecting it from healthy adults.Here, we propose a method that uses a fluff pulp diaper to collect urine. Urinary proteins are then eluted and adsorbed onto a piece of nitrocellulose membrane, which can be dried and stored in a vacuum bag. SDS-PAGE and LC-MS/MS analysis indicated that this method is reproducible, and similar proteins were identified as those obtained by an acetone precipitation method. With this simple and economical method, it is possible to collect and preserve urine samples from infants, toddlers, and patients with special needs, even for large-scale biomarker studies.展开更多
除自然干扰外,木材采伐是最能减少森林碳储量的人类活动之一。尽管目前大部分碳核算方法,均认为经由“可持续”管理的森林砍伐,其造成的温室气体排放可以忽略。但这种净碳核算的方法,并未赋予森林重新增长和未采伐森林的碳储存能力任何...除自然干扰外,木材采伐是最能减少森林碳储量的人类活动之一。尽管目前大部分碳核算方法,均认为经由“可持续”管理的森林砍伐,其造成的温室气体排放可以忽略。但这种净碳核算的方法,并未赋予森林重新增长和未采伐森林的碳储存能力任何价值。本研究以思茅松人工林生产一次性卫生用品为例,在CHARM模型的基础上结合产品生产消费特性,考虑时间的因素,估算人工林砍伐碳成本。结果表明,思茅松人工林的采伐碳成本为4.2~16.6 t C/ha,证实了采伐行为会造成碳损失,为进一步完善我国目前纸浆、纸、纸制品碳足迹核算方法提供了一定的参考。展开更多
基金This study was financially supported by Iranian National Science Foundation(project number of 4020345).
文摘This research aimed to investigate the effect of pulping conditions and refining intensities of wheat straw to be recommended for fluff pulp production.For this purpose,mono ethanol amine(MEA)was selected as a de-lignification agent at three levels of 50:50,25:75,and 15:85(MEA/water,W/V%),and soda-AQ 14 W/V%was used as a reference pulping.To investigate the optimal refining intensity,the obtained pulp was passed through a single disk laboratory refiner from 0 to 6 times and in two different consistencies(1.5 and 2.5 W/V%).Total yield,kappa number,ash content,and the Schopper-Riegler(SR°)freeness of the prepared pulps were investigated.Finally,hand sheets with a targeted basic weight of 70 g/m^(2) were made according to the related standards.The hand sheets were characterized using Fourier transform infrared(FTIR)spectroscopy and a field emission scanning electron microscope(FE-SEM).Sheet density,brightness,and mechanical properties such as burst,tensile,and tear indices were also investigated.The FE-SEM photographs showed that the texture of the hand sheet became denser as the refining intensity increased.External fibrillation on the surface of the fibers was also observed,especially on those refined with 2.5%consistency.The results of the chemical composition of wheat straw indicated that wheat straw containing a high percentage of holocellulose is an excellent candidate for the production of fluff pulp.The total yield and kappa number of MEA pulps increased with the decrease in MEA concentration.FTIR results indicated the presence of a peak related to amino groups in the pulp related to MEA pulp.The results also indicated that the mechanical properties of the papers,except for the tear index,were enhanced as the intensity of refining and the pulp consistency during refining increased.
基金supported by the National Key Research and Development Program of China(2016YFC1306300)the National Basic Research Program of China(2013CB530850)the Fundamental Research Funds for the Central Universities(11100704,10300-310421102)
文摘Change is the most fundamental property of a biomarker. In contrast to the blood, which is under homeostatic controls, urine reflects changes in the body earlier and is more sensitive, thus making it a better biomarker source. Moreover, drawing blood from infants and toddlers is difficult and not tolerated well. For patients limited by language, communicating their chief complaint is difficult. Thus, monitoring biomarkers in urine can provide valuable clues for the diagnosis of diseases, especially pediatric diseases. Collecting urine from young children and some adult patients is more challenging than collecting it from healthy adults.Here, we propose a method that uses a fluff pulp diaper to collect urine. Urinary proteins are then eluted and adsorbed onto a piece of nitrocellulose membrane, which can be dried and stored in a vacuum bag. SDS-PAGE and LC-MS/MS analysis indicated that this method is reproducible, and similar proteins were identified as those obtained by an acetone precipitation method. With this simple and economical method, it is possible to collect and preserve urine samples from infants, toddlers, and patients with special needs, even for large-scale biomarker studies.
文摘除自然干扰外,木材采伐是最能减少森林碳储量的人类活动之一。尽管目前大部分碳核算方法,均认为经由“可持续”管理的森林砍伐,其造成的温室气体排放可以忽略。但这种净碳核算的方法,并未赋予森林重新增长和未采伐森林的碳储存能力任何价值。本研究以思茅松人工林生产一次性卫生用品为例,在CHARM模型的基础上结合产品生产消费特性,考虑时间的因素,估算人工林砍伐碳成本。结果表明,思茅松人工林的采伐碳成本为4.2~16.6 t C/ha,证实了采伐行为会造成碳损失,为进一步完善我国目前纸浆、纸、纸制品碳足迹核算方法提供了一定的参考。
