scholarly journals Analysis of the Interaction Between Timber Markets and the Forest Resources of Maine

2004 ◽  
Vol 21 (3) ◽  
pp. 135-143 ◽  
Author(s):  
William G. Luppold ◽  
Paul E. Sendak

Abstract The abundant timber resources of Maine are critical to the State's timber economy; thus, when the 1995 forest inventory indicated a 20% decline in softwood growing stock, there was great concern by industry and government. Furthermore, declining near-term softwood growing stock levels were forecast. To better understand what was occurring in Maine's forest, we examined changes in composition and evaluated the relative impacts of harvesting versus growth and mortality. Much of the decline in spruce-fir inventory can be attributed to the budworm infestation of the 1970s and 1980s, although continued high utilization contributed to the decline. The high rate of softwood utilization was facilitated by low softwood timber prices due to increased supply from salvage cutting and high prices for softwood dimension lumber. The high price of dimension lumber also allowed the adoption of sawmill technology in Canada and Maine that used small-diameter logs, formerly consumed by the pulp industry, for lumber production. The increased demand for spruce-fir roundwood occurred during a period when changes in paper demand and pulping technology increased the demand for hardwood pulpwood. Unlike spruce-fir and hemlock, hardwood growing-stock volumes have increased steadily due to low utilization, high growth, and low mortality. Ample inventories of hardwoods have allowed increased volumes of these species to be used in the manufacture of pulp and engineered wood products. A recent partial forest survey of Maine indicated that spruce-fir growing stock inventory has stabilized as a result of regeneration of these species that began after the last spruce budworm infestation. North. J. Appl. For. 21(3):135–143.

2021 ◽  
Vol 71 (4) ◽  
pp. 371-378
Author(s):  
Azadwinder Singh Chahal ◽  
Jaya Tripathi ◽  
Daniel Ciolkosz ◽  
Sarah Wurzbacher ◽  
Michael Jacobson

Abstract Sufficiently valuing small-diameter-stem (diameter < 9 in.) woody material in Pennsylvania forest product markets may incentivize increased utilization of that material, a resource opportunity that would provide economic and ecological benefits to the state's forests and forest products community. Debarking is one primary process that could enhance the value of these small-diameter-stem materials for secondary markets. The wood products community in Pennsylvania was surveyed as to their perceptions of the status and value of economical small-diameter-stem debarking. The largest perceived current market for debarked, small-diameter-stem material identified by respondents is for chips for pulp and paper, and anticipated future demand is expected to be highest for chips for pulp and paper, chips for energy, and small-dimension lumber. Respondents who currently supply a given market tend to be more optimistic about that market than respondents who do not serve that particular market. Shredded wood/hog fuel and mulch are the two markets with the lowest overall scores for anticipated benefit of additional processing by debarking. Seventy-six percent of all respondents indicated that economical small-diameter-stem debarking would benefit their operation.


2021 ◽  
Vol 9 ◽  
pp. 205031212110147
Author(s):  
Nobuhiko Sumiyoshi ◽  
Kazuhiro Oinuma ◽  
Yoko Miura

Background: Adverse reactions to metal debris are significant complications after metal-on-metal total hip arthroplasty. Recently, late appearances of adverse reactions to metal debris and subsequent need for reoperations have been reported with small-diameter head metal-on-metal devices. We retrospectively investigated mid-term clinical outcomes of small-head metal-on-metal total hip arthroplasty. Methods: We reviewed 159 hips in 139 patients who had a small-head metal-on-metal total hip arthroplasty (M2a Taper; Biomet, Warsaw, IN) with a minimum 5-year follow-up and documented postoperative complications. Results: Focal osteolysis in either the femur or acetabulum was observed in 12 hips (7.5%, 44 months after surgery on average), with pseudotumor observed in 8 hips (5%, 120 months after surgery on average). Four hips (2.5%) had dislocations (84 months after surgery on average) and six hips (3.8%, 122 months after surgery on average) underwent reoperation. Conclusion: Small-head metal-on-metal total hip arthroplasty is associated with a high degree of complications at mid-term follow-up period. Considering this, we discourage the use of metal-on-metal total hip arthroplasty regardless of head size.


2008 ◽  
Vol 32 (1) ◽  
pp. 33-37 ◽  
Author(s):  
D. Andrew Scott ◽  
Allan Tiarks

Abstract Southern pine stands have the potential to provide significant feedstocks for the growing biomass energy and biofuel markets. Although initial feedstocks likely will come from low-value small-diameter trees, understory vegetation, and slash, a sustainable and continuous supply of biomass is necessary to support and grow a wood bioenergy market. As long as solidwood products are more valuable, bioenergy production will not be the primary market for southern pine. A study exploring a dual-cropping system for southern pine bioenergy and solidwood products was begun in 1982 in Louisiana to determine the phosphorus (P) nutritional requirements of the system. Fertilization of 60 kg ha−1 of P was required to produce 90% of the maximum volume at the age of 22 years. Direct-seeding pine in the interrows of a traditional pine plantation produced about 10.2 Mg ha−1 of biomass for energy at the age of 5 years but had no lasting effect on the planted pine height, diameter, or standing volume. The system is a viable method to produce both bioenergy and solidwood products. Herbaceous competition control and nitrogen (N) fertilization likely would make the system even more productive and profitable.


2001 ◽  
Vol 664 ◽  
Author(s):  
M. Kondo ◽  
S. Suzuki ◽  
Y. Nasuno ◽  
A. Matsuda

ABSTRACTWe have developed a plasma enhanced chemical vapor deposition (PECVD) technique for high-rate growth of µc-Si:H at low temperatures using hydrogen diluted monosilane source gas under high-pressure depletion conditions. It was found that material qualities deteriorate, e.g. crystallinity decreases and defect density increases with increasing growth rate mainly due to ion damage from the plasma. We have found that deuterium dilution improves not only the crystallinity but also defect density as compared to hydrogen dilution and that deuterium to hydrogen ratio incorporated in the film has a good correlation with crystallinity. The advantages of the deuterium dilution are ascribed to lower ion bombardment due to slower ambipolar diffusion of deuterium ion from the plasma. Further improvement of material quality has been achieved using a triode technique where a mesh electrode inserted between cathode and anode electrodes prevents from ion bombardment. In combination with a shower head cathode, the triode technique remarkably improves the crystallinity as well as defect density at a high growth rate. As a consequence, we have succeeded to obtain much better crystallinity and uniformity at 5.8 nm/s with a defect density of 2.6×1016cm−3. We also discuss the limiting factors of growth rate and material quality for µc-Si solar cells.


2011 ◽  
Vol 1321 ◽  
Author(s):  
Yasushi Sobajima ◽  
Chitose Sada ◽  
Akihisa Matsuda ◽  
Hiroaki Okamoto

ABSTRACTGrowth process of microcrystalline silicon (μc-Si:H) using plasma-enhanced chemicalvapor- deposition method under high-rate-growth condition has been studied for the control of optoelectronic properties in the resulting materials. We have found two important things for the spatial-defect distribution in the resulting μc-Si:H through a precise dangling-bond-density measurement, e. g., (1) dangling-bond defects are uniformly distributed in the bulk region of μc- Si:H films independent of their crystallite size and (2) large number of dangling bonds are located at the surface of μc-Si:H especially when the film is deposited at high growth rate. Starting procedure of film growth has been investigated as an important process to control the dangling-bond-defect density in the bulk region of resulting μc-Si:H through the change in the electron temperature by the presence of particulates produced at the starting period of the plasma. Deposition of Si-compress thin layer on μc-Si:H grown at high rate followed by thermal annealing has been proposed as an effective method to reduce the defect density at the surface of resulting μc-Si:H. Utilizing the starting-procedure-controlling method and the compress-layerdeposition method together with several interface-controlling methods, we have demonstrated the fabrication of high conversion-efficiency (9.27%) substrate-type (n-i-p) μc-Si:H solar cells whose intrinsic μc-Si:H layer is deposited at high growth rate of 2.3 nm/sec.


2014 ◽  
Vol 1070-1072 ◽  
pp. 85-90
Author(s):  
Hao Lv ◽  
Hao Ding ◽  
De Qun Zhou ◽  
Qin Zhang

The straw-based power generation, as a mature new energy utilization method, has been widely used in different countries. In this paper, we review the development of the straw-based power generation in China and divide it into three stages, namely, research and experimental stage, rapid developing stage and mature stage. Based on the analysis, it is found out that the straw-based power generation in China is now faced with profit loss. The underlying reasons include the high price of straw fuel, high operation and maintenance cost, large investment, low capacity utilization rate and high rate of power consumption in the production. We also propose the managerial suggestions to address the problems.


1992 ◽  
Vol 7 (2) ◽  
pp. 384-393 ◽  
Author(s):  
K.V. Ravi

Morphological instabilities attending the high growth rate of diamond films are examined. Pertinent literature on morphological instabilities and microstructure evolution in vapor deposited films is reviewed and theoretical treatments related to the case of diamond growth are discussed. Diamond films of various thicknesses have been synthesized utilizing the combustion flame synthesis technique involving diamond growth rates of ∼1 μm/min. Films of thicknesses under 20 μm are found to be dense and the surface smoothness of such films is governed by facets on the individual crystallites that make up the film. Increasing film thicknesses, at high growth rates, results in extremely rough surfaces, the trapping of voids and discontinuities, and the incorporation of non-diamond phases in the growing film. These characteristics are typical of morphological instabilities when surface diffusion and re-evaporation processes are absent and instability is promoted by the high rate arrival of the appropriate species from the flame ambient to the surface. Factors contributing to morphological instabilities include competitive shadowing and nutrient starvation and growth anisotropy of the different crystallographic faces on individual diamond crystals. It is shown that surface temperature and the presence of oxidizing species in the flame ambient contribute to anisotropic growth of diamond crystals and hence to morphological instabilities in diamond films. An approach to avoiding these instabilities is briefly discussed.


2008 ◽  
Vol 600-603 ◽  
pp. 111-114 ◽  
Author(s):  
Masahiko Ito ◽  
L. Storasta ◽  
Hidekazu Tsuchida

A vertical hot-wall type epi-reactor that makes it possible to simultaneously achieve both a high rate of epitaxial growth and large-area uniformity at the same time has been developed. A maximum growth rate of 250 µm/h is achieved at 1650 °C. Thickness uniformity of 1.1 % and doping uniformity of 6.7 % for a 65 mm radius area are achieved while maintaining a high growth rate of 79 µm/h. We also succeeded in growing a 280 µm-thick epilayer with excellent surface morphology and long carrier lifetime of ~1 µs on average. The LTPL spectrum shows free exciton peaks as dominant, and few impurity-related or intrinsic defect related peaks are observed. The DLTS measurement for an epilayer grown at 80 µm/h shows low trap concentrations of 1.2×1012 cm-3 for Z1/2 center and 6.3×1011 cm-3 for EH6/7 center, respectively.


2021 ◽  
Author(s):  
Arturo Aguirre Gómez ◽  
Laura Virginia Nuñez Balderas ◽  
Claudia Hidalgo Moreno ◽  
Jorge Dionisio Etchevers Barra

The chapter is meant to expose how a sound methodology can be instrumented to both, remediate acidic metal polluted mine wastes, taking advantage of the neutralizing power and high metal sorption affinity of biochar, and to utilize pyrolyzed material derived from high-rate growth plants (water hyacinth, Eichhornia crassipes Mart, and Eucalyptus, Eucalyptus globulus Labill), which have become of ecological relevance due to their unwanted proliferation over specific terrestrial, lacustrine or riverine environments. In addition, the proposal considers not only neutralizing the mine tailings and abating the toxic levels of specific heavy metals like Pb, Cd, Cu, Zn, etc., to fulfill the international and national standards and norms, but to conveniently combine biochar with widely used soil amendments to pass widely recognized biological tests of growth using heavy metal-sensitive plants. The approach addresses firstly: a) characterizing physiochemically mine tailings and biochar, in terms of their properties (metal speciation and contents, potential acidity and neutralization potential, chemical oxygen demand, heavy metal-biochar sorption-complexing affinities, among others), and secondly; b) creating a” fertile environment” by reconditioning, agriculturally, the heavy metal-polluted acidic mine waste to allow native vegetation, or other reforesting species, to regrow on the reclaimed site, based on the bioassay tests performances.


2002 ◽  
Vol 33 (1) ◽  
pp. 41-47
Author(s):  
W. Steyn ◽  
W. D. Hamman ◽  
E. V.D.M. Smit

A high growth rate may not be the ultimate measure of a successful company. This article shows that growth at too high a rate, for a company with a high non-cash working capital component, may lead to financial difficulties.While the income statement of a company is based on the accrual of income and expenses, the cash flow statement is based on the receipt and payment of cash. A company experiencing high sales growth, depending on the extent of its non-cash working capital, will find that the cash flow from operating activities before the payment of dividends will not grow as quickly as the net profit after taxation. This is because the accrual part included in the net profit after taxation is also growing at a high rate. At such a growth rate, operating activities do not generate sufficient cash to sustain the day-to-day activities of the company.


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