An economical treatment schedule for boron impregnation of Eucalyptus grandis wood: Commercial trial of partially dried material

Being non-durable, Eucalyptus grandis wood needs treatment with preservative chemicals. As vacuum-pressure impregnation treatment being more suitable for commercial applications, and boron chemicals being environment-friendly for indoor uses, an economical treatment schedule (15 minutes initial vacuum of -85 kPa followed by a pressure of 1300 kPa for 15 minutes and a final vacuum of -85 kPa for 5 minutes) developed at the Kerala Forest Research Institute was tested for its commercial suitability for treating E. grandis wood with boron chemicals. A pooled mean dry salt retention (DSR) of 7.7 kg m ^-3 was achieved for wood in partially dried condition with average moisture content of around 32%, using a 6% boric acid equivalent (BAE) solution. This confirms the success of the schedule for commercial application, as the DSR achieved is much higher than the standard specification of many countries.     

A pilot plant investigation of boron treatment of rubber wood: Arriving at an economical treatment schedule

An economical treatment schedule (15 minutes initial vacuum of 85kPa; 15 minutes pressure of 1000 kPa; 5 minutes final vacuum of 85kPa; was arrived at for treating air-dried rubber wood in a pilot plant cylinder. Treating with 3% BAE (boric acid equivalent) solution resulted in a dry salt retention of 13.1 kg/m³. Also, the study showed that green rubber wood can be treated to required chemical retention level by employing the above treatment schedule and by increasing the concentration of the treatment solution to 6% BAE.     

Optimizing the schedule for CCA impregnation treatment of rubber wood

could be achieved by using concentrations of the CCA solution of 2–4%, depending on moisture content and thickness of the wood. Also, it was found that the penetration and distribution of chemicals in the treated wood were throughout uniform. Chemical analysis revealed that the distribution of the constituents (copper, chromium and arsenic) of CCA in the treated timber conformed to the desired ratio. This study presents an economical and energy saving schedule for the treatment of rubber wood with CCA preservative. The applicability of the economical schedule developed was tested in two commercial scale treatment units and found suitable.     

Optimizing the schedule for CCA impregnation treatment of rubber wood

3 could be achieved by using concentrations of the CCA solution of 2–4%, depending on moisture content and thickness of the wood. Also, it was found that the penetration and distribution of chemicals in the treated wood were throughout uniform. Chemical analysis revealed that the distribution of the constituents (copper, chromium and arsenic) of CCA in the treated timber conformed to the desired ratio. This study presents an economical and energy saving schedule for the treatment of rubber wood with CCA preservative. The applicability of the economical schedule developed was tested in two commercial scale treatment units and found suitable.     

Development of new wood treatments combining boron impregnation and thermo modification: effect of additives on boron leachability

Environmental pressures in France and in most European countries during the last decade have led to the development of more environmentally acceptable preservation methods. In this context, wood heat treatment is one of the most investigated alternative methods. Important chemical modifications resulting from thermo-degradation reactions confer new properties to wood, like increased decay resistance or higher dimensional stability, while mechanical properties like tensile strength decrease after treatment. However, the improved durability of heat treated wood is not sufficient to allow its utilization in ground contact, where it is subjected to insect and fungi attacks. Impregnation with borax before thermal treatment could be an interesting method to improve the properties of thermally modified wood. Boron is a relatively harmless biocide that improves resistance to fungi and insects like termites. Additionally, borax can also improve wood fire resistance due to its fire retardant effect. To reduce boron leachability, two additives previously developed in the laboratory corresponding to water soluble polymerizable polyglycerol derivatives were added to the borax solution, taking advantage of thermal treatment to fix the latter through polymerization within the wood structure limiting boron leachability.     

Kinematic characterization of the pressure-dependent PCM impregnation process for radiata pine wood samples

This paper reports on the properties of Pinus radiata wood impregnated with an organic phase change material (O-PCM). The tests are aimed at characterizing the kinetics of impregnation (rates, flows, and fronts) and the thermophysical properties (thermal conductivity and specific heat). In particular, a paraffin type O-PCM (octadecane) is used to impregnate dry radiata pine wood in the tangential flow direction at four manometric pressures (0, 1, 2, and 3 bar) and constant temperature of 50 °C. The wood is sapwood from 12-year old P. radiata growing in the Bío-Bío region and dimensioned according to Chilean standard for treated wood sample extraction. The results show that it is viable to impregnate P. radiata wood with O-PCM to improve its thermophysical properties with the purpose of passive conditioning.     

帘子布浸胶处理速度比微机监测系统的研制

在帘子布生产过程中,为了实现对速度比的动态监测,研制开发了帘子布浸胶处理速度比微机监测系统。系统的硬件组成包括脉冲检测与整形电路、逻辑控制电路、ＳＴＤ工业控制机、速度比上下限设定电路、计数器及其控制电路、模拟脉冲发生电路;软件采用ＭＣＳ－５１汇编语言编程,包括主程序和中断服务程序。实践证明,该系统对纺织行业的诸如上浆过程的速度比监测有较好的借鉴意义。     

中小产量刨花板生产线热压机的选择

单层热压机和多层热压机在国内外刨花板生产中都得到了较为广泛的应用。刨花板生产选用单层热压机好还是选用多层热压机好?本文笔者将以年产15000m^3刨花板生产线为例介绍两种热压机的优缺点，并对两种生产线总体经济效益进行分析，以供中小产量刨花板生产线热压机选型时参考。     

Optimisation of an accelerated drying schedule for regrowth eucalyptus pilularis Sm

Measurements of strain gradients, sets, moisture gradients, and length, width and depth of checks were made during the kiln drying from green of 100×50 mm backsawn Eucalyptus pilularism Sm. Two conventional kiln runs established the likely limits for relative humidity and temperature necessary to produce timber complying with the requirements of “Appearance Structural Grade No. 1” in Australian Standard (AS) 2082–1979. These limits were then used to develop an accelerated schedule. In the first trial of an accelerated schedule, the timber dried in half the time of the control (conventional) run, but deep face checks and unacceptable internal checks developed. The second trial of an accelerated schedule dried timber in 63% of the time of the conventional schedule for the same level of degrade. Energy consumption and severity of collapse are likely to be reduced using the accelerated schedule. The initiation of very small internal checks in some boards just prior to reconditioning suggests that this schedule is the most severe that can be used to accelerate the drying of this timber without causing down-grading of the quality under AS 2082–1979. Using a similar methodology and sequence of kiln runs, it should be possible to optimise an accelerated drying schedule for any species and thickness, once the acceptable levels of surface and internal checking have been defined.     

酶处理法制备木质材料微/纳纤丝的研究进展

木质材料制备的微/纳纤丝具有生物可降解、高强度、导热低等诸多优点,是一种环境友好型材料。本文简单介绍了普通法制备微/纳纤丝的特点,同时具体介绍了酶处理法制备微/纳纤丝的国内外研究进展。从木质纤维素中分离的微/纳纤丝添加到聚合物中后,聚合物的强度、热稳定性等性质会得到显著提高。     

Properties of an organokaolin-modified soybean meal-based adhesive used for adhering cotton fabric to wood composites

European Journal of Wood and Wood Products - Fabrics with various patterns and textures can be used to decorate the surface of wood and/or wood composites, enriching indoor environments and...     

Experimental verification of an orthotropic finite element model for numerical simulations of ultrasonic testing of wood poles

Ultrasonic testing is a non-destructive and non-invasive method which has been used for internal condition assessment of wood poles in electric transmission and distribution lines. The reliability of this method of evaluation relies on a good understanding of propagation of ultrasonic waves in wood. However, a full-waveform analysis in ultrasonic testing is rarely performed in practice because of difficulties in establishing realistic values for the elastic parameters, modeling the material damping and characterizing the dynamic response of an ultrasonic transmitter. In this paper, a calibrated orthotropic finite element model for numerical simulations of ultrasonic testing of a sound red pine pole is presented. In the calibrated model, the dynamic modulus of elasticity in the radial and tangential directions, Poisson’s ratio and damping ratios are estimated from ultrasonic testing; whereas the dynamic modulus of elasticity in the longitudinal direction is estimated from transverse-vibration testing. The measured response of an ultrasonic transmitter to a one-cycle sinusoidal pulse of 50 kHz is used as dynamic excitation and introduced in the numerical model as displacement-time history. Results of the first arrival of compression waves and the frequency response magnitude computed at three receiver locations are in good agreement with the obtained ones from ultrasonic testing. The calibrated orthotropic finite element model will be used for a better understanding of propagation of surface and compression waves in ultrasonic testing for the detection of early stages of decay in wood poles.     

Randomized noninferiority field trial evaluating cephapirin sodium for treatment of nonsevere clinical mastitis

The general objective of this study was to evaluate whether cephapirin sodium is noninferior compared with a positive control broad-spectrum product formulated with a combination of antimicrobials for intramammary treatment of nonsevere clinical mastitis. In addition, we compared the efficacy of treatments on the cure risks of pathogen groups (gram-positive, gram-negative, and cultures with no growth) based on culture results. A total of 346 cows distributed in 31 commercial dairy herds were selected to participate in the study, although only 236 met the criteria for evaluation of microbiological cure. Coagulase-negative staphylococci were the most isolated gram-positive pathogens in pretreatment milk samples, whereas the most common gram-negative bacterium was Escherichia coli. Cows attending the postadmission criteria were treated with 4 intramammary infusions (12 h apart) of one of the following antimicrobials: 300 mg of cephapirin sodium + 20 mg of prednisolone (CS), or the positive control treatment formulated with a combination of antimicrobials (200 mg of tetracycline + 250 mg of neomycin + 28 mg of bacitracin + 10 mg of prednisolone; TNB). Noninferiority analysis and mixed regression models (overall and considering the pathogen groups) were performed for the following outcomes: bacteriological cure (absence of the causative pathogens in cultures performed in milk samples collected at 14 and 21 ± 3 d after enrollment), pathogen cure (absence of any pathogen on both follow-up samples), clinical cure (absence of clinical sign in the milk and mammary gland at 48 h after the last antimicrobial infusion), extended clinical cure (normal milk and normal gland on the second posttreatment sample collection (d 21), and linear score of somatic cell count cure [linear score of somatic cell count recovery (≤4.0) on d 21 ± 3 after enrollment]. No significant differences were observed between treatments regarding any of the evaluated outcomes in both regression models (overall and considering the pathogen groups). Noninferiority of CS relative to TNB was inconclusive for bacteriological cure (CS = 0.68; TNB = 0.73) and clinical cure (CS = 0.88; TNB = 0.94), as the confidence intervals crossed the pre-stated margin of noninferiority (Δ = ?0.15). Cephapirin sodium was noninferior compared with TNB for pathogen cure (CS = 0.36; TNB = 0.35), extended clinical cure (CS = 0.93; TNB = 0.92), and linear score of somatic cell count cure (CS = 0.29; TNB = 0.28). In conclusion, the use of intramammary CS for treatment of nonsevere clinical mastitis has similar efficacy as a treatment regimen with a combination of antimicrobial agents (tetracycline + neomycin + bacitracin), although noninferiority analysis showed inconclusive results for bacteriological and clinical cures.     

"十一五"印染行业经济运行回顾及2011年展望

"十一五"期间,我国印染行业克服国际纺织品贸易摩擦加剧、全球金融危机、人民币升值加快、原料成本持续攀升的困境,印染行业运行整体向好:产量产值持续增长,运行质量和效益提高,内需拉动作用增强.在国家节能减排、淘汰落后产能的政策指引下,行业结构调整取得进展,转型升级加快推进,国际竞争力提升;淘汰落后产能效果显著,节能减排扎实推进.2011年预计印染行业将保持稳定增长,发展方式也将从资源数量型增长转向质量型增长.     

Application of artificial neural networks and Monte Carlo method for predicting the reliability of RF phytosanitary treatment of wood

One of the biggest challenges during phytosanitary treatment of wood packaging material is to ascertain that all the boards subjected to the treatment reach the final prescribed temperature (i.e. 56 °C for 30 min during conventional heating and 60 °C for 1 min during dielectric heating) across the wood profile including core as per ISPM 15. This study represents a first attempt to find a tool that can be used to reveal the reliability of the phytosanitary treatment that is achieved by means of dielectric heating at radio frequencies (RF). The tool proposed in this work consists of an artificial neural network (ANN) based model that is solved by means of Monte Carlo method. The data set that was used in this work was collected from the literature. The results indicate that the developed ANN model can reasonably predict (R²?=?0.72) the final temperature of boards during dielectric heating at radio frequencies. To predict the reliability of the RF phytosanitary treatment by means of the developed ANN model, three input variables are considered as random variables, namely, green moisture content, power density and initial temperature of wood. Once the model is solved for a large number of times and the performance function that separates the failure domain from the success domain is defined, the reliability of the phytosanitary treatment could be obtained. Since the reliability of the RF phytosanitary treatment is known at various time spans, the optimal treatment time is revealed.