The effect of open air conditions on the properties of wooden material

In this study, the impregnation materials of Tanalith-C (CCA) and Protim 230 WR were used as preservative and water repellant. Wooden materials were taken from beech and black pine. The sampleswere made subject to weathering conditions for one year. At the end of this period, changes occurred in the samples’ bending strength, compression strength and physical properties were examined. As a result of this study, it was observed that no significant variations occurred in mechanical values of the impregnated samples; however, severe losses occurred in case of the non-impregnated samples. It was seen that impregnation type provides different protection according to the type of the wooden material.It was observed that discoloration is more significant in the  on-impregnated samples compared with those impregnated. Both of the impregnation materials provide sufficient protection

Growth and Survival of Baldcypress Planted in an Old Ricefield of Coastal South Carolina

Vast acreages of baldcypress [Taxodium distichum (L.) Rich.] swampland in coastal South Carolina were cleared for rice production starting in the late 1600s. When rice cultivation ended in the late 1800s, many cultivated areas becamemarshlands. Other fields failed to return to forest unless they were planted. In one such area, nine acres were planted with baldcypress in 1956 by MeadWestvaco near Walterboro, SC. Seedlings were planted on an 8- by 8-foot spacing. Beginning in November 1991, five 0.12-acre plots were established within the stand to monitor tree growth and survival and measured yearly. In addition to baldcypress, the stand now contains red maple (Acer rubrum L.), black willow (Salix nigra Marsh.), sweetgum (Liquidambar styraciflua L.), and persimmon (Diospyros virginiana L.). The number of trees per acre declined from 600 to 402 by year 2000. Average diameter of trees after 44 years was 9.1 inches. In 2001, MeadWestvaco clearcut half of the stand, thinned 1/4 of the stand, and left 1/4 intact. All stems were removed from the clearcut section, and the thinned section was reduced to 104 stems per acre (88 percent of remaining trees are baldcypress). Five regeneration plots were placed in the clearcut area to follow future regeneration patterns

Mathematical knowledge and skills expected by higher education in engineering and the social sciences: Implications for high school mathematics curriculum

Cataloged from PDF version of article.One important function of school mathematics curriculum is to prepare high school students with the knowledge and skills needed for university education. Identifying them empirically will help making sound decisions about the contents of high school mathematics curriculum. It will also help students to make informed choices in course selection at high school. In this study, we surveyed university faculty members who teach first year university students about the mathematical knowledge and skills that they would like to see in incoming high school graduates. Data were collected from 122 faculty members from social science (history, law, psychology) and engineering departments (electrical/electronics and computer engineering). Participants were asked to indicate which high school mathematics topics and skills they thought were important to be successful at university education in their field. Results were compared across social science and engineering departments. Implications were drawn for curriculum specialists, students, and mathematics educators

Optimization of reactor temperature according to radiation distribution characteristics

Papers presented to the 11th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 20-23 July 2015.Temperature stability inside a solar reactor is much more complex to achieve than that of traditional combustion based reactors. The main reason contributes to the transient nature of the solar radiation which serves as the source of high temperature process heat to run endothermic solar thermochemical reactions. One of the key factors to assure temperature stability inside a solar reactor is to understand the characteristics of the incoming solar radiation and design a solar reactor accordingly. This paper provides radiation distribution characteristics of 7 kW high flux solar simulator and design of a solar reactor according to that heat source. Flux characterization of the solar simulator was done by using a calorimetric calibration of a heat flux gage. The maximum and minimum peak flux output at the focal plane was obtained by moving the heat flux gage within the focal plane, but away from the focal point by 0.25 mm steps. Heat exchange between the gage and the Lambertian target was quantified by measuring the inlet and outlet temperatures. Flux map obtained per experimental measurements was used to determine corresponding aperture size of the solar reactor for various flux levels. Selection of representative flux levels were made based upon NREL database which was fit to the flux scale of the 7 kW solar simulator. An optimum aperture size for the solar simulator was calculated for various corresponding time of the day per incoming flux based on two different optimization methods and input parameters in order to maintain a constant reactor temperature. It was found that the maximum optimal aperture radius during sunset at 5 am varies between 1.8 cm and 3.52 cm for the methods used, whereas it decreases to 0.4 cm and 0.73 cm during midday. Optimal constant reactor temperatures for corresponding aperture sizes change between 1339 K and 854 K per method used and flux distribution measured.am201

Firefly-inspired Heartbeat Synchronization in Overlay Networks

Heartbeat synchronization strives to have nodes in a distributed system generate periodic, local “heartbeat” events approximately at the same time. Many useful distributed protocols rely on the existence of such heart-beats for driving their cycle-based execution. Yet, solving the problem in environments where nodes are unreliable and messages are subject to delays and failures is non-trivial. We present a heartbeat synchronization protocol for overlay networks inspired by mathematical models of flash synchronization in certain species of fireflies. In our protocol, nodes send flash messages to their neighbors when a local heartbeat triggers. They adjust the phase of their next heartbeat based on incoming flash messages using an algorithm inspired by mathematical models of firefly synchronization. We report simulation results of the protocol in various realistic failure scenarios typical in overlay networks and show that synchronization emerges even when messages can have significant delay subject to large jitter

Secondary metabolites of Phlomis viscosa and their biological activities

Further phytochemical studies on the aerial parts of Phlomis viscosa (Lamiaceae) led to the isolation of 24 compounds: 3 iridoid glycosides, 10 phenylethanoid glycosides, a megastigmane glycoside and a hydroquinone glycoside, as well as 2 lignan glucosides and 7 neolignan glucosides, 1 of which is new (17b). Compound 17b was obtained as a minor component of an inseparable mixture (2:1) of 2 neolignan glucosides (17a/b), and characterized as 3',4-O-dimethylcedrusin 9-O-b -glucopyranoside. Full NMR data of the known 8-O-4' neolignan glucoside, erythro-1-(4-O-b-glucopyranosyl-3-methoxyphenyl)- 2-{2-methoxyl-4-[1-(E)-propene-3-ol]-phenoxyl}-propane-1,3-diol (18) are also reported. All isolated compounds were screened for cell growth inhibition versus 3 tumor cell lines (MCF7, NCI-H460, and SF-268) and several phenylethanoid glycosides were found to possess weak antitumoral activity. The phenylethanoid glycosides were also evaluated for their free radical (DPPH) scavenging, antibacterial and antifungal activities. The free radical (DPPH) scavenging activities of verbascoside (4), isoacteoside (5), forsythoside B (10), myricoside (13) and samioside (14) were found to be comparable to that of dl-a -tocopherol. Compounds 4, 5, 10 and 14 (MIC: 500 m g/mL) as well as Leucosceptoside A (8) and 13 (MIC:1000 m g/mL) showed very weak activity against Gram (+) bacteria

Forested Wetlands of the Southern United States: A Bibliography

The term forested wetland covers a variety of forest types including mangroves, cypress/tupelo swamps, bottomland hardwoods, pocosins and Carolina bays, flatwoods, and mountain fens. These forests are dominated by woody species that have morphological features, physiological adaptations, and/or reproductive strategies enabling them to achieve maturity and reproduce in an environment where the soils within the rooting zone may be inundated or saturated for various periods during the growing season. Although alluvial floodplains occur along most streams of the United States, they are most extensive in the Atlantic Coastal Plain, Gulf Coastal Plain, and Mississippi Alluvial Plain. Only about half of the original floodplain forests remained by the 1930s, and conversion to agriculture continued at an accelerated pace during the 1960s and 1970s.The purpose of this bibliography is to provide a detailed listing of references for students and researchers of the varied studies conducted in these forest types

Monitoring of trace metals, biochemical composition and growth of Axillary seabream (Pagellus acarne Risso, 1827) in offshore Copper alloy net cage

The study was conducted to assess trace metal contents, biochemical composition and growth performance of axillary seabream (Pagellus acarne Risso, 1827) cultured in a copper alloy mesh cage. A total of 400 axillary seabream (initial mean weight: 176.0±14.0 g), a new candidate species for the Mediterranean aquaculture, were stocked into a high-density polyethylene frame gravity cage and fed a commercial seabream diet for a period of 6 months. At the end of the feeding trial, fish reached a final weight of 264.8±16.8 g with a weight increase of 88.8 g and a feed conversion rate of 2.51. Overall, relative growth rate, specific growth rate and feed conversion ratio were satisfactory and comparable to the pelagic fishes such as gilthead seabream or European seabass, which are presently the main fish species for the Mediterranean aquaculture industry. Trace elements in fish grown in copper alloy net cages over a 6-month period showed satisfactory results, as the metal concentrations in fish tissues such as liver, skin, muscle and gills were below the reported upper limits for human consumption, indicating that copper alloy net is an acceptable and safe material for finfish cage aquaculture. Furthermore, from the growth performance data obtained in the present study, it can be concluded that axillary seabream showed potential for cage farming, and thus is a promising new candidate for the Mediterranean aquaculture industry