吊丝单竹、云南甜竹、大头典竹出笋规律调查与分析

通过对吊丝单竹、云南甜竹、大头典竹在相同抚育措施下出笋规律调查,结果表明:吊丝单竹出笋早,出笋量大,平均达37.05支/丛,但出笋总重量低,平均仅25.25kg/丛,云南甜竹、大头典竹出笋迟,但云南甜竹的笋总产量最高,达42.2kg/丛,大头典竹出笋产量仅次,达40.1kg/丛。从方差分析上看,吊丝单竹与云南甜竹、大头典竹间存在1%极显著水平。从出笋的月规律变化上看,7月下旬和8月中旬均是3种竹子出笋高峰期,而7月中旬和8月上旬均出现出笋低谷期,8月中旬过后均出现出笋逐渐减少趋势,吊丝单竹、大头典竹9月下旬产笋仅零星出现,云南甜竹出笋则在9月下旬仍达到一个小高潮,而后出笋逐渐停止。     

Surface deterioration of moso bamboo (<Emphasis Type="Italic">Phyllostachys pubescens</Emphasis>) induced by exposure to artificial sunlight

The effect of ultraviolet-visible light irradiation on changes in surface chemistry and morphology of moso bamboo (Phyllostachys pubescens Mazel) was investigated. Fourier transform infrared (FT-IR) and FT-Raman spectroscopy were used in combination to study chemical changes induced by exposure to artificial sunlight (xenon lamp) for up to 160 h, and the resulting physical changes of cell walls of bamboo surfaces were examined by scanning electron microscopy (SEM). FT-IR results showed that significant changes occurred in the lignin component as indicated by considerable decreases in the intensities of the characteristic aromatic lignin peak at 1512 cm⁻¹ and other associated bands. This was accompanied by formation of new carbonyl groups at 1735 cm⁻¹, resulting in photooxidation of bamboo surfaces. The photosensitive nature of bamboo lignin was also demonstrated by FT-Raman analysis, in which obvious decreases in intensities of Raman bands at 1604 and 1630 cm⁻¹ mainly derived from lignin and free and esterified p-coumaric and ferulic acids were observed. SEM micrographs of the irradiated cross sections of bamboo revealed that significant damage occurred to the fiber walls, whereas the parenchyma cells exhibited slight distortion and some cracks occurred in the cell walls. The structures of cell corners and middle lamellae were nearly intact after irradiation.     

Intercalation of wood charcoal with sulfuric acid

Intercalation of wood charcoal with sulfuric acid (H₂SO₄) was investigated. Carbonized sugi (Japanese cedar) samples were prepared by heating at various temperatures in the range 1700°–2700°C. Electrochemical oxidization was carried out in H₂SO₄ and the feasibility of intercalation was determined. In potentiometric analysis, plateaus appeared for samples carbonized at temperatures above 2300°C. In their X-ray diffraction profiles, the peak at around 26° was shifted to a smaller angle of about 22.4°. These results can be considered as signs of intercalation with acid molecules. Fourier transform infrared analysis of charcoal heated at 2700°C, following washing with water and drying of the sample, showed a band at 1220 cm⁻¹ that was assigned to a sulfonate group. This band was not observed for samples heated at 1900°C. These observations suggest the occurrence of intercalation in the former charcoal, but not in the latter. It is concluded that wood charcoal can undergo intercalation when it has ordered stacking of hexagonal carbon layers. Part of this article was presented at the 55th, 56th, and 57th Annual Meetings of the Japan Wood Research Society, Akita, Hiroshima, and Tsukuba, August 2006, August 2007, and March 2008, respectively, and at the International Conference on Carbon “CARBON 2008,” Nagano, July 2008     

Environmentally benign methods for producing green culms of ma bamboo (<Emphasis Type="Italic">Dendrocalamus latiflorus</Emphasis>) and moso bamboo (<Emphasis Type="Italic">Phyllostachys pubescens</Emphasis>)

The objective of this study was to find an effective method for treating ma bamboo (Dendrocalamus latiflorus) and moso bamboo (Phyllostachys pubescens) using new water-based reagents containing copper. The effects of green-color protection using various treatments on bamboo culms were examined in this study. Two methods were used: heating in a water bath and ultrasonic dipping. The results revealed that excellent green-color protection (a* value of −6.2) was obtained when ma bamboo culms were treated with 0.25% ammoniacal copper quaternary compound-type B (ACQ-B) in a water bath at 100°C for 2 h. It was also found that the wettability of bamboo epidermis increasedsignificantly after pretreatment in a mixture of 1% KOH and surfactant in a water bath at 100°C for 30 min. Furthermore, pretreated moso bamboo culms exhibited excellent green-color protection after they were treated with 0.25% ACQ-B at 100°C for 2 h (a* value of −8.2). This novel treatment method definitely endows the bamboo culms with a fascinating green skin color and consequently could increase the economic value of bamboo products. No improvement in green-color protection was found when ultrasonic energy was added to the water bath at ambient temperature.     

生物改性竹炭对污水净化效果的研究

对不同最终炭化温度(300~700℃)的竹炭进行比表面的测定,结果表明炭化温度为700℃的竹炭具有较大的比表面积(385m²/g)。将炭化温度为700℃的竹炭进行生物改性处理,利用竹炭本身的吸附能力及微生物菌群的生物降解作用,对污水进行处理,实验结果表明:生物改性竹炭对污水中COD去除率达到94.00%,氨氮的去除率达到96.67%,色度去除率达到88.73%,浊度去除率达到92.56%。通过扫描电镜分析生物改性竹炭,观察到竹炭的表面和内部孔隙均分布着丰富的微生物菌群。可见,以竹炭作为载体,为微生物聚集、繁殖生长提供了良好的场所,在适当的温度及营养条件下,能够同时发挥竹炭的吸附作用和微生物的生物降解作用,使水质得到净化。     

蜂窝状活性竹炭帘的研制及在水净化处理中的应用

利用竹炭具有较好的吸附作用和六角形分子稳固结构的性能,将竹质活性炭、壳聚糖、纤维素及添加剂合成蜂窝状活性竹炭帘应用于水污染处理,解决了传统活性炭无法固定、机械强度不足、吸附后无法脱释的问题。在生物法污水处理中,可为微生物成长环境提供生长膜,节约大量的絮凝剂,用于臭氧法污水处理降解COD可起到再生脱释,达到重复利用、持续吸附的目的。     

竹炭对水中余氯吸附性能的研究

通过对竹炭吸附水中余氯影响因素的考察,系统研究了竹炭对水中余氯的吸附性能。结果表明:竹炭对水中余氯有较好的去除效果,用炭化温度400℃、粒径<0.112mm的竹炭2.0g,在20℃条件下振荡吸附2h,处理浓度为25mg/L余氯水溶液350mL时,竹炭对余氯的去除率达95.50%。根据Langmuir和Freundlich吸附等温模型对试验数据进行了拟合,结果表明,当余氯浓度在10~30mg/L范围内时,竹炭对水中余氯的吸附符合Freundlich等温线方程。     

竹炭的神奇功能 人类的健康卫士

介绍了竹炭的生产工艺、性能及微观结构。竹炭的微观结构非常类似洋葱状富勒烯碳和展开的碳纳米管结构,因而具有许多木炭不具有的特殊功能。由于竹炭具有较大的比表面积,有良好的吸附性能,可用于有害气体的脱除和水体的净化。竹炭的孔隙以大孔为主(200nm),可用作纳米光催化剂或生物膜的载体,制备纳米改性光催化剂杀菌吸附用炭以及可循环使用的生物膜改性竹炭,实现了两种材料两种性能完美的结合,并可解决竹炭吸附饱和的现象。     

Changes of carbon stocks in bamboo stands in China during 100 years

Bamboo stands are one of the most important forest types in China, covering an area of about 4.99 million hectares, and estimation of their carbon stocks is vital for China's national carbon accounting. Bamboo biomass and carbon fraction, as well as soil bulk density and soil organic matter content, data were collated from 40 publications describing conditions at 35 sites in 10 Chinese provinces where most bamboo stands are distributed. Carbon stocks and its changes in the living biomass and soil organic matter in bamboo stands in China in the past five decades were estimated based on these collated data together with the area of bamboo stands and number of bamboo culms derived from the National Forestry Inventory (NFI). Our estimates indicate that the carbon stocks in bamboo stands in China have been increasing since the 1950s with estimated values of 318.55 Tg  C (1950–1962), 427.37 Tg C (1977–1981), 463.80 Tg C (1984–1988), 493.00 Tg C (1989–1993), 548.79 Tg C (1994–1998) and 631.58 Tg C (1999–2003) accompanying the increase of bamboo stand area. Based on correlation between forest area and bamboo area, as well as the trends of forest area predicted in government strategy documents for forest development over the next five decades, the carbon stocks in bamboo stands for 2010, 2020, 2030, 2040 and 2050 are estimated to be 727.08 Tg C, 839.16 Tg C, 914.43 Tg C, 966.803 Tg C and 1017.64 Tg C, respectively.     

利用森林可燃物制炭的初步研究

用昆明地区8种森林可燃物制成了11种成型炭,实验表明：11种成型炭与2种实木制成的炭的热值相近。将森林可燃物固化制成成型炭可减少林内可燃物载量,经济、生态效益显著。