Zusammensetzung und Eluierbarkeit von Aschen aus industriellen Feuerungsanlagen holzverarbeitender Betriebe

Investigations of ash originating from the combustion of wood debris and/or waste wood in the wood industry are described. Their contents of the major elements calcium, potassium, sodium, magnesium, manganese and iron and of the trace elements arsenic, boron, chlorine, chromium, fluorine and zinc as well as the leachability according to the German DIN 38414 part 4 are reported.     

Systematische Untersuchungen der Wirkung aggressiver Gase auf Fichtenholz

In part 2 the effects of the aggressive gases formaldehyde, ammonia, sulfur dioxide and chlorine on lignin and polysaccharides in spruce wood are described. Formaldehyde causes no degradation of lignin and only minor changes in the polysaccharides. The degradation of lignin by NH₃, SO₂ and Cl₂ is increased in varying degrees by a high water content. The cell wall swelling during NH₃ treatment improves the alkali solubility of polyoses. The cellulose structures are attacked at their surfaces by NH₃, SO₂ hydrolytically cleaves polyoses and less ordered cellulose. Chlorine also penetrates the cellulose structures and causes intensive degradation. A high water content of the wood samples impedes this degrading effect of chlorine.     

Systematische Untersuchungen der Wirkung aggressiver Gase auf Fichtenholz

In extension of previously described chemical investigations on spruce wood treated with formaldehyde, ammonia, sulfur dioxide and chlorine, sorption experiments were made applying the same gases. The wood samples treated with gases were also tested in bending stress. Wood absorbs ammonia very quickly, but the gas is only slightly bound. The absorption of chlorine takes place only slowly, but chlorine is almost completely bound. In contrast to NH₃ and Cl₂ more SO₂ is absorbed with increasing moisture of wood. While treatments with formaldehyde and NH₃ cause an increase of wood strength, treatment with SO₂ causes a minor, treatment with Cl₂ a deep drop in strength respectively. All results of the chemical and physical investigations are finally compiled in a schedule giving an estimate of the effects of aggressive gases on spruce wood.     

Holzfeuchteminderung und -ausgleich durch Wechseldruckvortrocknung von schwachem Buchenstammholz

The objective of this study was to assess, whether it is possible to reduce and to level out cross sectional wood moisture contents in thin beech timber through mechanical wood demoistening, i. e. a regime of alternating atmospheric high and ambient pressure. For this purpose, 25 pieces of beech timber of up to 30 cm mid diameter and 2.80 m length were treated in a pressure chamber. Their wood moisture content and cross sectional wood moisture distribution were compared to 26 untreated controls. The treated beech timber had significantly lower wood moisture contents as compared to untreated controls. Furthermore, wood moisture was significantly more evenly distributed across the trunks. Neither untreated controls nor treated samples had noticeable wood moisture gradients from the stem periphery to the centre. Instead, wood moisture was distributed irregularly across the trunks.     

Holzfeuchteminderung und -ausgleich durch Wechseldruckvortrocknung von schwachem Buchenstammholz

The objective of this study was to assess, whether it is possible to reduce and to level out cross sectional wood moisture contents in thin beech timber through mechanical wood demoistening, i. e. a regime of alternating atmospheric high and ambient pressure. For this purpose, 25 pieces of beech timber of up to 30 cm mid diameter and 2.80 m length were treated in a pressure chamber. Their wood moisture content and cross sectional wood moisture distribution were compared to 26 untreated controls. The treated beech timber had significantly lower wood moisture contents as compared to untreated controls. Furthermore, wood moisture was significantly more evenly distributed across the trunks. Neither untreated controls nor treated samples had noticeable wood moisture gradients from the stem periphery to the centre. Instead, wood moisture was distributed irregularly across the trunks.     

Systematische Untersuchungen der Wirkung aggressive Gase auf Fichtenholz

The investigations' objective was to give information about the chemical and structural changes in wood, caused by the influence of various aggressive gases. Small rods of sprucewood with different wood moisture contents were treated with formaldehyde, ammonia, sulphur dioxide, and chlorine over a period of 336 days. Decomposition products were removed in three extraction steps (water, ethanol-benzene, alkali), followed by the analyses of the extracts and the extracted wood residues. The present results reveal that wood is decomposed only slightly by formaldehyde and ammonia. The decomposition by sulphur dioxide is rather restricted, at least at room temperature. A strong decomposition of the wood components was found after treatment with chlorine.     

兴安落叶松化学组成的研究

对兴安落叶松化学组成进行较深入分析研究，表明其特性如下：提取物含量较高，尤以热水提取物最甚，主要含阿拉伯糖基－半乳聚糖。苯醇提取物中除主要含树脂外，还有相当量的黄酮类化合物。总木质素含量与一般针叶材类似，但酸溶木质素很低；综纤维素含量比一般木材都低，其糖基组成分析表明在测定过程中阿拉伯糖基－半乳聚糖基本上流失，因此综纤维素含量的测定不宜采用现行的标准方法；灰分含量较低，但有２３种元素组成，其主要元素为Ｃａ、Ｋ、Ｍｎ和Ｍｇ。     

Bohrwiderstandsmessungen an Laubbäumen und ihre holzanatomische Interpretation

The determination of the drill resistance is a technique for assessing the stability of trees. In the case of broad-leaf trees, however, the interpretation of these measurements is still unreliable. Therefore, profiles of the drill resistance of broad-leaf trees have been made and compared to the local wood anatomy. Intrinsic factors such as wood density and moisture content were considered, as well as pathogenic alterations in the wood and factors involved in the measuring technique. The drill penetration measurements provide information on the structure and status of the interior wood of tree trunks. They also indicate the growth level and any abrupt changes in growth, but do not enable the complete identification of all tree-ring borders. The profiles are modified by the wood moisture. Factors connected with the drilling process have to be taken into account when interpreting the measurements. In the case of pathogenically altered wood, the peaks of the drill resistance profiles were explained by means of scanning electron microscopy. In comparison to white rot, brown rot causes a reduction in drill resistance even at lower values of dry weight loss.     

荧光分光光度法测定淀粉及其衍生物中二氧化硫残留量研究

建立荧光分光光度法测定淀粉及其衍生物中二氧化硫残留量的方法。在弱酸性条件下,以邻苯二甲醛/铵盐为荧光指示剂,亚硫酸氢钠为定量标准,荧光强度作为考察指标,测定样品中的二氧化硫残留量。结果表明,标准曲线的线性回归方程为Y=23.22X+ 0.854,线性相关系数R2=0.999 8、检出限为0.732 mg/kg、加标回收率在95.3%～104.8%之间、精密度良好、检测结果可靠。荧光分光光度法可以作为淀粉及其衍生物中二氧化硫残留量的测定方法。     

Zum Brandverhalten von gipsgebundenen Spanplatten

The fire behaviour of gypsum-bonded laboratory particleboards with varying wood contents ranging from 15 to 40% was investigated. Chips from poplar, pine and alder and from old particleboards were used to manufacture the test boards. In some test variants chips were used that had been treated with fire retardants. Board density ranged from 950 kg/m³ to 1300 kg/m³. Fire behaviour was assessed by means of the furnace test according to DIN 4102, the determination of calorific potential and smoke density measurements. The results presented in this paper show that the fire behaviour of gypsum-bonded particleboards can be influenced to a large extent by the wood/gypsum ratio as well as by density. The investigations proved that with a wood content below 25% gypsum bonded particleboards may reach the classification “structural material class A2” of DIN 4102. Up to a wood content of 35% the maximum temperature increase in the furnace test remained below the standard requirement of 50 K. Flame height and fire duration were within the standard boundary values only up to a wood content of 25%. The use of fire retardants for wood chips led mainly to a retardation in flame development and hence to a distinctly curtailed fire duration. Concerning smoke density measurements good correlation existed between smoke development and wood content. Independent of the method selected to test the boards values were found to lie considerably below the required boundary values, especially for wood contents in the range of 15 to 25%.     

木材原料中金属离子的测定及分布的研究

利用原子吸收光谱测定了有代表性的几种针叶木和阔叶木原料中金属元素分布及含量,并利用扫描电镜—能谱仪分析了原料的不同部位中金属离子的分布规律。结果发现在实验范围内,各种木材原料中都存在由多种金属离子构成的复杂体系;不同种原料中金属离子的含量和成分存在着很大差异;针叶木Ｆｅ、Ｍｎ 含量显著,高于阔叶木;同种原料中,边材金属离子含量一般高于心材;不同生长环境会导致木材金属离子分布出现差异。纸浆中的金属离子主要来源于原料本身,因此对金属离子含量不同的原料,纸浆漂前的除过渡金属离子预处理条件应该不同。     

碱法麦草浆减氯漂白的研究

论述了有机胺和无机铵盐及表面活性剂在碱法麦草浆次氯酸钠漂白中的助漂、减氯及提高白度的作用，研究了不同助剂用量对纸浆白度和残余有效氯的影响。研究结果表明：使用这些助剂可以明显地提高纸浆白度，节省漂白用氯量和减少漂白废液中残余有效氯的含量。     

Möglichkeiten zum Nachweis des Klebstoffanteils in beleimten Spänen

NIR-spectroscopy allows the quantification of the resin portion in wood chips. A laboratory system with 3 wavelengths and an industrial system for measuring the moisture content of wood particles was used. It was found that type and producer of the resin are very important. The determination of resin content in wood particles using a commercial system for measuring particle moisture content is feasible. It is important to study the optimization of these systems.     

文山烟区土壤和烟叶氯素特征及影响因子研究

为深入了解文山植烟土壤和烟叶水溶性氯含量分布状况,并解析其影响因素,采用GPS定位技术采集了276份土壤和381份烟叶,对土壤氯和烟叶水溶性氯含量进行测定,采用经典统计学和地统计学方法,对其分布及部分影响因素进行了研究。结果表明,该烟区土壤水溶性氯平均含量为13.81 mg/kg,61.95%区域氯元素含量在适宜范围内（10.00~30.00 mg/kg）;烟叶水溶性氯含量普遍较低,平均含量为0.15%,变异系数为113.33%,仅有8.66%的烟样氯含量在适宜范围（0.30%~0.80%）,低（0.10%~0.30%）和极低（<0.10%）的烟样占比分别为37.27%和51.71%。降水的强淋溶作用是导致文山烟叶氯元素偏低的重要原因。因此,文山烟区土壤氯元素含量适宜烤烟种植,但烟叶氯素含量均偏低,建议适当加强含氯肥料的施用,并做好对氯元素的动态监测,以提高烟叶品质。     

Zur Berechnung des Feuchteverhaltens von Bauteilen aus Holz und Holzwerkstoffen

Special functions of transport coefficients are required for the calculative simulation of climatically caused moisture transport processes in wooden construction elements by means of an existing computer program. It is to be stated which moisture properties for wood and wood based materials are available and how far they are suitable for the determination of the new coefficients.     

利用近红外光谱技术快速测定木材水分和气干密度的研究

利用近红外光谱技术对木材水分和气干密度进行了快速测定。结果表明：两个水分模型的决定系数都接近1,RMSECV值小于0.2%,RPD值大于10,模型质量极好,对样品的预测偏差小于0.2%;气干密度模型的决定系数为0.976、RM-SECV值为0.0152g/cm^3、RPD值为6.47,模型质量好,对样品的预测偏差范围为-0.019～0.02g/cm^3。说明可以利用近红外光谱技术对我国造纸木材的水分和气干密度进行快速、准确的预测。     

Einfluß der Dämpfung und Trocknung von Furnieren auf deren Acetylgruppengehalt und die Formaldehydabgabe von Sperrholz

In this study, the effect of log steaming and veneer drying on acetyl group content of wood and subsequent formaldehyde emission of plywood produced were investigated. This work was carried out on pine (Pinus brutia Ten.) and beech (Fagus oriantalis Lipsky) species. Changes in acetyl group contents were determined by Freudenberg, method and IR-spectra. Formaldehyde emission was determined by WKI-bottle and perferator methods. Pronounced changes were observed in acetyl group contents due to log steaming and veneer drying. Amount of formaldehyde emission occuring in pine plywood was found to be higher than that of the beech plywood. Lower formaldehyde emission was obtained in plywoods produced using veneers with rich acetyl group content.     

基于粗糙集属性约简法的植烟土壤肥力评价分析

为建立更合理的植烟土壤评价方法,以江苏中烟某原料基地的植烟土壤为研究对象,采用层次分析法和基于粗糙集的属性约简法对土壤肥力的综合状况进行评价,并利用当年的烟叶产量对评价结果进行检验。结果表明:①15个采样点土壤肥力指标间的差异不同,其中有机质、碱解氮、水溶性氯、速效磷、速效钾、有效硫和有效镁含量（质量分数）7项指标差异较大,全钾、有效硼、有效钼、有效钙含量（质量分数）和土壤pH 5项指标差异较小,采样点的全氮和全磷含量（质量分数）指标差异不显著。②经多重比较筛选并利用层次分析法确定有机质、碱解氮、速效磷、速效钾、有效镁和水溶性氯含量的初始权重分别为0.229、0.357、0.120、0.189、0.055、0.050。③基于粗糙集的属性约简法确定的最小近似约简为有机质、速效磷、速效钾和水溶性氯含量指标,权重系数分别为0.214、0.214、0.321和0.251。④利用层次分析法和基于粗糙集的属性约简法得到的土壤综合肥力评价结果不尽相同,不同方法计算得到的土壤综合肥力指数与当年的烟叶产量均呈显著线性相关,相关系数（r）值分别为0.65和0.92,决定系数（R2）分别为0.42和0.86,均方根误差（RMSE）分别为5.92和5.89,基于粗糙集属性约简法的相关性更好,精度更高。      

Borbestimmung im Holz durch Extraktion mit Mannitol

A new methode for isolation of boron in impregnated wood, based on the extraction with mannitol was developed as a result of extensive experiments. Depending on the boron concentration the determination of the content is performed either by titration with an adapted ?mannit-methode” or by fotometry with azomethin. This method is suitable to detect boron contents down to 5 ppm in samples free of heavy metals. Attention has to be paid to the natural boron content in plants varying between 10 to 20 ppm for beech, spruce and pine     

影响耕地白糖SO2含量的主要因素及其机理探讨

我国的白砂糖产品SO2残留量普遍较高.本文经试验研究,分析了影响耕地白砂糖SO2含量的物理化学反应机理.认为导致糖浆和白砂糖SO2含量高的主要原因是甘蔗原料品质差,澄清工艺条件波动大,清汁胶体物、酚类色素和铁含量高,煮糖操作水平低.