40 research outputs found
Determining effective criteria on sustainable development of fluting paper making industry
Fluting paper industry seems to be significant from environmental view point. Accordingly, study on sustainable development criteria in this sector of Iran’s industry is regarded as a national necessity. The intent of the current study is to determine and prioritize the indices affecting sustainable development of Iran’s fluting paper industry by benefiting from Analytical Hierarchy Process (AHP) method. After the conducted investigations, 55 indices were identified and categories in eight general groups namely, technical & human, cultural-social, economic, materials & products, rules and regulations, environmental, infrastructure and sale & marketing . Analytical Hierarchy Process was applied in the form of adjusting and distributing questionnaires among professional experts. Results show that the highest priorities for attaining sustainable development in this industry respectively belong to sub-criteria of economic stability increase in the country, a continuous relation between university and industry, privatization, training man force, paper recycling, foreign investment, increasing productivity and reducing greenhouse gas emissions
EFFECTS OF POLY-ALUMINUM CHLORIDE, STARCH , ALUM AND ROSIN ON THE ROSIN SIZING, STRENGTH AND MICROSCOPIC APPEARANCE OF PAPER PREPARED FROM OLD CORRUGATED CONTAINER (OCC) PULP
The influence of rosin (0.1-0.3%), alum (0.4-0.6%), polyaluminum chloride (0.3-0.7%), and starch (0.5-1.5%) in the making of paper from old corrugated container (OCC) pulp on the freeness, breaking length, tear index, and burst index of pulp and paper sheets was studied. Using a full factorial design to identify the optimum operating conditions, equations relating the dependent variables to the operational variables of the chemical additives were derived that reproduced the former with errors lower than 5%. Using a high starch (1.5%), high PAC (0.7%), low alum (0.4%), and low rosin (0.1%) combination led to pulp that was sufficient to obtain paper with good strength properties (breaking length 5720m; burst index: 3.1 kPam2g-1; tear index: 6.2mNm2/g; Cobb test: 94; fold endurance: 1.52) SEM analysis show increasing in bonding between fibers together at this level of additives. The influence of starch on Cobb test values was not significant
The potential use of organosilane water soluble nanomaterials as water vapor diffusion retarders for wood
The retarding effect of organosilane water soluble nanomaterials (nano-zycosil and nano-zycofil) on water vapor diffusion through poplar wood (P.nigra) was evaluated in comparison with that of clear coatings (sealer and nitrocellulose lacquer and polyester lacquer) using cup and sorption methods. Two drying methods were applied to dry the nanomaterials -coated substrates: oven drying at temperature of 103 ± 2 °C for 24 h. and climatically drying at temperature of 25 °C and relative humidity of 65% for 20 minutes. The results showed that both coating materials decreased the water vapor diffusion rate through the wood. The sealer and nitrocellulose lacquer coating represented a stronger effect on the diffusion coefficient of wood compared to the other coatings. In this case, the nano-zycosil represented a better performance compared to the nano-zycofil. Furthermore, the drying method of the nanomaterials -coated substrates can impact the nanomaterials performance. The water vapor diffusion through the oven-dried substrates was faster than that through the climatically dried ones
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Proof of Concept for the Autobiographical Memory Flexibility (MemFlex) Intervention for Posttraumatic Stress Disorder.
Autobiographical memory distortions are a key feature of posttraumatic stress disorder (PTSD). In this proof-of-concept randomized controlled trial (N = 43), we evaluated an autobiographical memory flexibility intervention, MemFlex. We aimed to determine whether the mechanism-focused intervention, which aims to improve autobiographical memory processes, may also affect other cognitive predictors of PTSD and potentially reduce PTSD symptoms in Iranian trauma survivors diagnosed with PTSD. Results indicated significant, moderate to large between-groups effect sizes in favor of MemFlex, relative to wait-list control, for the targeted cognitive mechanism of autobiographical memory flexibility and PTSD symptoms. A large, significant effect was also observed on maladaptive posttraumatic cognitions-a strong predictor of PTSD prognosis, which is a key target of high-intensity cognitive therapies for PTSD. Findings support future completion of a scaled-up trial to evaluate treatment efficacy of MemFlex for PTSD to determine whether MemFlex may offer a culturally adaptive, low-cost, low-intensity intervention able to improve cognitive mechanisms of PTSD
Impaired Autobiographical Memory Flexibility in Iranian Trauma Survivors With Posttraumatic Stress Disorder
Reduced ability to retrieve specific autobiographical memories is a well-defined feature of posttraumatic stress disorder (PTSD), and science-driven interventions have emerged to improve memory specificity and thereby symptoms. However, research in depressed samples indicates that the ability to flexibly move between retrieval of specific and general memory types (i.e., memory flexibility) may more accurately conceptualize autobiographical memory deficits in emotional disturbance. In this study, we evaluated memory specificity and memory flexibility in Iranian trauma survivors (N = 63) with and without PTSD relative to community control participants. Trauma-exposed participants had experienced a serious road-traffic accident. Results indicated that individuals with PTSD experienced reduced memory specificity and memory flexibility relative to trauma-exposed participants and community control participants. A small sample size limits the strength of conclusions, although good statistical power was obtained. Findings suggest that reduced memory flexibility may be a transdiagnostic marker of emotional disturbance and support further development of memory flexibility interventions for PTSD
A hybrid MCDM approach for ranking suppliers by considering ethical factors
One of the negative effects of
cooperating with un-ethically
behaving suppliers is that it
may devastate the companies'
credibility among employees,
customers and the public. In this
paper, a hybrid Multiple Criteria
Decision Making (MCDM) approach
(Disjunctive-WPM method) is
proposed to resolve this limitation.
The proposed methods consist of
the following steps: 1. drop unethical
solutions and 2. rank the
remaining solutions. Therefore,
the aim of this paper is the
application of the DisjunctiveWPM
method to supplier selection
problem by adding ethical factors
into the analysis. In addition,
a comparative analysis to the
traditional WMP method is carried
out. The proposed method appears
to be more satisfactory than the
traditional method in solving this
kind of decision problems. The
main findings of this study confirm
the applicability of the proposed
approach
Silver-nanoparticle-impregnated cellulose nanofiber coating for packaging paper
In this study, antimicrobial packaging was prepared by mixing colloidal silver nanoparticles with cellulose nanofiber (CNF) and depositing this hybrid coating (CNF/Ag) as a layer on different paper substrates. The CNF/Ag-coated papers were then characterized by scanning electron microscopy (SEM). In addition, their antimicrobial activity, and barrier and strength properties were assessed. SEM showed deposition of Ag nanoparticles on the surface of CNF and formation of a relatively smooth, dense coating layer on the paper surface. The results also demonstrated that the CNF/Ag coating exhibited good antibacterial activity against Escherichia coli (Gramnegative) and Staphylococcus aureus (Gram-positive) bacteria. Although the coating coverage was influenced by paper surface characteristics and coat weights, almost all properties (except water absorption of greaseproof paper) including the water vapor transmission rate, oil resistance, and tensile strength of the CNF/Ag-coated papers were improved in comparison with uncoated papersPostprint (published version
In situ synthesis of silver nanoparticles on fiber matrix for preparing antibacterial paper
In this study, the preparation of antibacterial paper was carried out using in situ synthesis of silver nanoparticles (AgNPs) on bleached cellulosic fiber matrix through chemical reduction of silver nitrate (AgNO3) by two reducing agents of sodium borohydride (NaBH4) and formaldehyde (HCHO) under different molar ratio conditions. After synthesis, during the fabrication of hand-sheets, about 0.05% polyethyleneimine (PEI) was added to fiber suspension as retention aid to promote linking between fiber and nano-particles. The produced papers were then characterized by X-Ray Diffraction (XRD), UV-visible spectra analysis and scanning electron microscopy (SEM). In addition, the antimicrobial activity of AgNPs loaded papers was assessed. From the UV spectroscopy and antibacterial activity results, it was found that by increasing the molar ratio of HCHO:AgNO3 and NaBH4:AgNO3, the maximum absorption, minimum wavelength, minimum particle size, maximum amount of produced nano-silvers and maximum percentage reduction of E. coli (Gram-negative) and S. aureus (Gram-positive) can be obtained. The optimum synthesized samples were gained at 0.05:0.001 ratio in which the formation of agglomerates was minimum. According to the electron microscopy images and X-ray diffraction results, nano-silver particles were formed in a spherical shape with an average crystallite size of 10-100 nm and located mainly on the surface of the fibers. Furthermore, it was demonstrated that the formation of unstable AgNPs agglomerates makes formaldehyde inferior to sodium borohydride as an efficient reductive agent. The contribution of PEI in retention and immobilization of AgNPs against washing and drainage during synthesis and hand-sheet making process was confirmed by SEM images. Hence, it could play an important role in controlling and reducing the migration of the silver particles to the environment. The present results show that in situ synthesis of AgNPs in fiber matrix can provide an appropriate approach in developing antibacterial paper-based productsPostprint (published version