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1.
Majid AZIZI 《中国林学(英文版)》2013,15(4):349-356
In Iran, due to abundant restrictions on harvesting wood from northern forests by implementing the preservation project and also lack of possibility for sufficient wood production, development of the area of planting poplar is quite inevitable. Poplar wood properties have special importance to produce many wood production, particularly pulp and paper. Paper factories are the major consumers of poplar wood at the global level and this is because of unique morphological, physical, mechanical and technological properties of poplar wood. Therefore, regarding the importance of using this species in making various printing and writing paper, packaging or carton, cardboard and newsprint, in this study, costs of poplar production in one hectare including planting and harvesting were examined and determined. Then, based on conversion coefficients of FAO, required round wood, productivity and the cost of poplar wood were calculated for the producing various kinds of paper. The results indicate that carton and cardboard paper or packaging allocate the lowest cost and highest return, while printing and writing paper had highest cost and lowest return in terms of poplar wood supply needed for paper production. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1-4):54-65
Analysis of consumer demand for packaging suggests that: plastic packaging is a luxury good, while paper packaging is a normal good, paper packaging demand increases with the price of plastic packaging, and that demand for paper packaging is most sensitive to its own price, and to the income of consumers. In a complementary analysis of input demand in the converting paper industry it was found that the demand for each paper grade is price inelastic, capital and other materials are substitutes for paper, while labor is a complement, technical change rapidly decreases the use of unbleached kraft packaging and industrial converting, and increases the use of other grades. The demand for each paper grade, derived from the consumer demand and the factor demand functions, showed that, from 1983 to 1991, the demand for paper in packaging was influenced mainly by consumer income, and by the price of paper packaging, and less so by the price of paper itself, or by the price of plastic packaging. 相似文献
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Tamer Y. A. Fahmy Fardous Mobarak Magda G. El-Meligy 《Wood Science and Technology》2008,42(8):691-698
This work introduces, for the first time worldwide, undeinked recycled old newsprint as a new resource of electrical purposes
paper. Impregnation of undeinked recycled old newsprint paper with linseed oil enhances the breaking length of paper and remarkably
improves its electrical properties, i.e., the dielectric constant increases greatly and the a.c. conductivity decreases significantly
due to impregnation. It was found that the electrical properties of the undeinked old newsprint paper and its linseed oil
impregnated counterpart are close to the electrical properties of paper made from the more expensive virgin wood pulps and
their linseed oil impregnated counterparts. Using the undeinked pulp is more privileged than using the deinked pulp; because
eliminating the deinking step saves money, time, and reagents. In addition, eliminating the deinking step improved the breaking
length of paper. Electron dispersive X-ray elemental analysis (EDX) was used to investigate the undeinked and deinked pulps
for residual elements originating from the printing materials. EDX was correlated to the slight differences in electrical
properties of paper made from undeinked and deinked pulps. However, impregnation was able to overcome these slight differences.
It was shown that improvement in electrical properties, due to impregnation, is sustained at elevated temperatures. 相似文献
4.
过去20多年, 北美地区的杨树已经从杂草树种转变为产生巨大经济效益的用材林树种, 杨树木材因其具有较高纤维素含量和较低的木质素含量, 适合用作纸浆和纸制品的原料。杨木制浆方法有机械法、化学法、半化学法和化学机械法, 杨木浆可以作为高级纸、纸板、新闻纸和包装纸。杨木牛皮纸浆与针叶材牛皮纸浆混合, 具有良好的成纸性能, 透明度高, 适合制作高级用纸。杨木也是传统的锯材、单板和胶合板工业的原材料, 用来生产锯材、单板、胶合板、木质复合板、包装箱、集装箱、火柴杆和筷子等。最近10年杨木定向刨花板和结构复合板产量显著增加, 利用前景广阔。从资源生产的角度来看, 在改良木材化学组成、纤维质量和自然耐久性等方面进行木材性质改良的转基因杨树研究取得了长足进展。从资源利用角度来看, 高价值的工程复合板和高得率的纸浆和纸产品将会在未来发展中快速增长。 相似文献
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Confocal laser scanning microscopy was applied to visualize inside fibers stained with a fluorescent dye, and the fiber orientation
distribution in the thickness direction was determined by image analysis from optically sliced images. Fiber orientation angle
and anisotropy were determined by the fast Fourier transform method, which holds advantages over the conventionally applied
Hough transform with regard to evaluation of fiber width-weighted contribution and intrafiber segmental contribution. An orthogonally
layered Japanese paper handmade by the flow-sheet forming method resulted in a clear change of fiber orientation angle from
0° to 90°. Machine-made wood-containing printing paper showed the highest anisotropy, while copier paper showed a low anisotropy.
Thick papers like the wood-free paperboard and recycled packaging board showed that the maximum measured thickness was about
150 μm. The depth limit to detect fluorescence was considered to depend on the apparent density of the paper and the light absorption
character of the fibers.
Part of this study was presented at the 54th Annual Meeting of the Japan Wood Research Society, Sapporo, Japan, August 2004 相似文献
8.
《Scandinavian Journal of Forest Research》2012,27(4):358-373
Static and dynamic models of the derived demand for forest product imports were estimated for each of 10 major forest products covering industrial roundwood, wood-based panels, pulp, and paper and paperboard. The models were estimated with panel data from 64 countries for 1970–1987, by pooled ordinary least squares, first differencing, fixed effects, random effects and the Arellano–Bond approach. The predictive accuracy of the demand equations was tested with postsample data from 1988–1997. Based on multiple criteria, the best results were obtained with the dynamic model estimated by the Arellano–Bond method. For most products the demand for imports was found to be inelastic with respect to price. For all products the demand for imports was elastic with respect to income. 相似文献
9.
随着纸及纸板生产与消费数量的不断提高,我国造纸工业结构调整的发展对木材原料的需求将持续增加。我国木材市场数据显示,以原木、锯材等为代表的木材原料,以木浆、木片为代表的造纸原料进口均呈平稳增长趋势,木材市场供需矛盾突出。造纸工业竞争的核心是木材原料的争夺,而我国木材市场自有木材供给的严重不足性和进口总量的绝对依赖性特征决定了造纸工业木材原料未来仍将依靠进口。 相似文献
10.
Utilization of softwoods in Great Britain 总被引：1，自引：0，他引：1
The change in scale in wood processing in the UK over the past70 years is huge. From a position where sawmilling was on smallscale satisfying local market needs with native broadleaf species,it is now a huge industry supplying about 26 per cent of oursawn softwood demand; mainly from the exotic, Sitka spruce. Development has seen the industry reach levels of technologyequivalent to those in the Nordic countries and north America. Seventy years ago the only board manufacturing plants were producingplywood from imported tropical logs. Now the board industriesproduce chipboards, strand boards, MDF and cement bonded particleboardsfrom the home grownresource. Overall we produce some 56 percent of UK consumption of these products whilst in the growingMDF sector home production represents 78 per cent of demand. The wood pulp industry has developed over the past 15–20years from a position where it had almost ceased to exist tothe present situation of large volumes of newsprint, magazinepapers, packaging board and fluting being produced, largelyon four capital intensive sites. The sawmilling, board manufacturing and pulp and paper industriesare mutually dependent upon one another for their successfuloperation. Residue material from sawmills, for example, providesan important income source, whilst the market for small roundwoodprovides cash flow for forest owners prior to felling of thefinal sawlog crop. 相似文献
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林产品化学利用是指以木质和非木质林产品为原料,经化学加工制备国民经济所需的各种产品.主要包括木材制浆造纸、木质活性炭、松脂化学加工、植物单宁、林产精油、植物提取物等.近年来中国林产化学工业发展较快,特别是建设林纸一体化工程,为发展木材制浆工业,改变中国制浆造纸工业原料结构创造了良好的条件,按计划2005年木浆产量将达380万t,2010年达750万t.松香产量已超过50万t/a,出口约30万t/a.木质活性炭产量达6万t/a.随着我国经济的发展对林化产品的需求将进一步扩大. 相似文献
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以环保、可持续利用和传承传统文化为设计指导思想,针对目前市场上中药材包装存在的问题,文章提出了湖南雪峰山地区中药材(天麻、金银花)包装的4种设计方案。这些设计方案将传统竹藤编织工艺贯穿到中药材包装设计的材料选择、结构优化、视觉元素提炼等环节,展示了雪峰山中药材的文化性、历史性、艺术性和生态性,使包装拥有简洁、自然、环保的设计风格,传递出一种人与自然和谐相处的生活理念,引导人们健康生活。包装设计凸显了地域文化特征,可提升雪峰山地区中药材产品的附加值,满足市场多元化需求,对于构建雪峰山中药材的地域性IP、服务乡村特色产业发展具有重要意义。 相似文献
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随着我国产品的商业附加值迅速提升,纸质包装机械生产企业的产能出现阶段性过剩,如何实现纸质包装机械生产企业去产能,成为许多企业亟待解决的问题。论述了我国包装纸行业概况,分析了包装纸机械市场需求,在此基础上,提出了纸质包装机械生产企业去产能措施。 相似文献
14.
This study has evaluated the factors affecting the utilization of alternative fiber resources and efforts have also been made
to outline the possible alternative fiber resources available in the country. Since 1989, paper consumption has exceeded production.
Imports of industrial paper have increased and the future of newsprint export is dark. The government sector pulp and paper
mills are highly dependent on forest based fiber resources and private sector paper and board mills depend on imported pulps.
Uneven distribution of fiber resources has limited the raw material availability of the pulp and paper mills. Shortage of
raw materials, irregular procurements, and low installed capacity are the main reasons for low paper production. On the other
hand, paper demand will increase tremendously in the near future. But the present raw material availability is not sufficient
to cope with the future demand for attaining self sufficiency in paper production. Therefore, immediate action is necessary
for utilizing alternative fiber resources. Rangpur region has abundant lower grade jute. Jute cutting is available in Narayangonj
area. Available bagasse supply is expected in the northwest regions after the end of this century. These resources are more
than enough for supplementing the shortage of present raw materials during the 1997–2006 period.
This is a revised of “Study of Non-wood and Forest Based Fiber Resources in Bangladesh — A Case Study on Pulp and Paper Industry”
presented in the '95 TAPPI Pulping Conference. Ref.
Proceedings 1995 Pulping Conference—Chicago, Book 2, TAPPI Press, Atlanta, 1995, 597–603. 相似文献
15.
This paper compares the financial attractiveness of forest and agroforestry plantations promoted by external organizations
with tree growing practices of Amazonian smallholders. Based on 80 case studies and interviews with 112 forestry professionals
from Brazil, Bolivia, Peru and Ecuador, the paper characterizes the economic, environmental and structural implications, and
identifies the respective financial costs and benefits. Six case studies provided data for in-depth financial analyses. The
results showed that the expectations of externally promoted smallholder tree and agroforestry plantations were not met. Despite
significant inputs, smallholders generated at best annual net incomes of US$200–$200–1,000 per ha from NTFP plantations, and up
to US$800–$800–1,000 from timber plantations in the year of harvest. This corresponded to around one-third of the initially expected
returns. Overall, only around 1% of the smallholders participating in such initiatives managed to produce and commercialize
any plantation products. Smallholders’ practices of complementary tree growing in conjunction with agriculture and managing
natural regeneration of timber and NTFP products were often underestimated by professionals. They required low input, didn’t
rely on external support, were highly flexible in risky environments, and some presented financial returns comparable to some
well functioning plantations. 相似文献
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出口欧盟的纸和纸板需要经过ISEGA认证,在ISEGA认证中包括纸和纸板抗茵成分迁移测试（EN1104）、FDA检测项目,本文主要介绍纸和纸板抗茵成分迁移测试的基本方法原理以及相关影响因素。 相似文献
18.
Rural inhabitants make considerable use of wild resources from communal areas around their settlements, as well as from arable and residential plots. These wild resources compete with the main crops planted in arable plots and home gardens, but play a significant economic and nutritional role in rural livelihoods. This paper reports upon a conservative financial evaluation of the wild plant resources harvested from home gardens and arable plots by inhabitants of rural village in the Bushbuckridge lowveld (South Africa), and examines their importance relative to other domesticated crops. On average, each household made use of four to five species of wild plants growing on their residential plot, whereas the mean number of crop plants was 3.4. The total value of all plants was R1694 (US$ 269) per household per year, or approximately R4200 (US$ 667) per hectare of home garden per year. Wild plants represented 31% of the value of all plants grown on residential plots, relative to the 69% for domesticated crops (including fruit trees). Approximately 72% of the total value of all plant products was consumed by the household, and the remaining 28% was sold.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
19.
广西国家级自然保护区与周边社区协调发展研究——以十万大山和并岗自然保护区为例 总被引：2，自引：1，他引：1
就保护区与社区间的协调发展问题对广西弄岗、十万大山2个国家级自然保护区周边社区居民进行问卷调查．运用SPSS15．0对调查问卷中的11个指标进行因子分析,确定出4个公共因子,即：周边社区居民对保护区生态效益的认识,保护区相关制度与周边社区相互影响,保护区对周边社区发展的经济影响,社区共管．并从这4个方面对2个保护区与社区间的协调发展情况进行分析,找出发展过程中存在的矛盾,藉此提出提高社区居民对保护区的认识水平,解决社区居民在能源需求、经济发展等方面的实际问题,增强社区共管力度等国家级自然保护区与周边社区协调发展对策和建议． 相似文献
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湘西南山区是湖南省社会经济相对落后的区域，山区人地生态系统复杂而又具特殊性，在总结目前城步苗族自治县人地生态与经济发展现状的基础上，运用衡量可持续发展的新指标，即生态足迹理论方法对该县2000年的生态足迹进行了分析评价，发现该县经济发展规模在其所提供的生态承载力范围内，但生产性生态土地生产力水平低，因而对该县实现人地生态系统可持续发展的模式做了初步探讨。 相似文献