超临界CO2萃取测定食品中总脂肪的研究

超临界CO2(S-CO2)萃取用于测定食品中的总脂肪含量，是一种很有前途的方法。文中具体介绍了测定总脂肪的S-CO2萃取法，并对其测定结果进行了统计分析，S-CO2萃取法用于全脂奶粉和营养奶粉总脂肪的测定，其浸提率分别为97．4％和98．4％。另外，S-CO2法萃取的总脂肪中主要脂肪酸种类及其含量与碱性乙醚萃取法相近。     

二乔木兰花粉萌发特性及其保存方法的研究

通过使用不同的培养基,采用液体培养法研究了蔗糖、硼酸和钙离子对二乔木兰花粉萌发的影响。将所用花粉分为两组,组1于8:00采集,组2于16:00采集,结果表明:一定浓度的蔗糖、硼酸和钙离子对花粉的萌发有较大的促进作用,但超过一定浓度时则起抑制作用,二乔木兰花粉萌发的最适培养基为30 g·L~-1蔗糖 100mg·L~-1硼酸 500 mg·L~-1Ca~2 ,在该培养基内,组1花粉的萌发率为46．21%±1．86%,花粉管长度为1156．25Um;组2花粉的萌发率仅为14．22%±1．86%,花粉管长度为1022um。此外,在其离体萌发过程中,二乔木兰花粉存在花粉管双萌发的现象。用不同的花粉保存方法保存二乔木兰花粉后,发现干燥处理后于-18℃下保存的花粉活性最高,30d后仍有6．92%±0．75%的萌发率,而于常温25℃下保存的花粉10d后就基本失活,说明低温干燥保存是保存二乔木兰花粉活性的有效途径。     

Sorption of Cr(VI) on the wood of Japanese larch treated with concentrated sulfuric acid

A carbonaceous sorbent was prepared from the wood of Japanese larch (Larix leptolepis) by dehydration with concentrated sulfuric acid in a 69% yield. The abilities of the sorbent to remove Cr(VI) from aqueous solutions were investigated. Research parameters included the initial solution pH, temperature, and initial concentration of Cr(VI) in solution. The removal of Cr(VI) was highly solution pH dependent and was mainly governed by physicochemical sorption under weak acidic conditions. The equilibrium data fit well in the Langmuir isotherm model. The Langmuir constants were calculated at different temperatures, and the sorption capacity increased with rising temperature, indicating the endothermic nature of the Cr(VI) sorption onto the sorbent. The desorption experiments suggest that the Cr(VI) sorption is generally irreversible, owing to strong interaction of HCrO ₄ ⁻ with the active sites of the sorbent.     

萃取余甘子籽油及其成分研究

利用超临界CO2萃取(SCDE)技术,采用响应面优化法(RSR),对广东惠州野生余甘子籽油的萃取进行了研究.结果表明,500g余甘子籽萃取余甘子籽油的最佳工艺条件为:萃取时间103min,萃取压力19 MPa,萃取温度35℃,在此工艺条件下余甘子籽油得率为26.13%±1.4%.通过GC-MS分析表明,余甘子籽油中含有16种脂肪酸,主要为油酸、亚油酸、亚麻酸和花生四烯酸等不饱和脂肪酸,总GC含量达91.33%.通过分析油的理化参数及生产成本表明,超临界CO2萃取余甘子籽油是一个好的方法,具有工业使用价值.     

雷竹鞭侧芽发育过程中核酸含量,过氧化物酶和淀粉酶同工酶的变化

雷竹鞭侧芽从潜伏芽、饱满芽发育为萌发芽、强萌发芽，核酸含量有规律地显著上升，潜伏芽与饱满芽过氧化物酶的活性和变化有相同的规律，总体活性较强，笋期后活性急剧上升，而和萌发芽、强萌发芽有显著差异；不同类型侧芽，过氧化物酶和淀粉酶同工酶明显不同，存在遗传信息顺序表达的规律，这种表达是内外环境相互作用的结果；从核酸含量、过氧化物酶的活性及其同工酶和淀粉同工酶变化看，从潜伏芽、饱满芽到（强）萌发芽，从萌发芽萌发到笋是两个较为独立的变化过程。     

COMPOSITION ANALYSIS AND RESEARCH DEVELOPMENT OF NORTHERN FOREST ANTS

INTRoDUCTIoNAnthasbeenusedasmedicineandhealthprotectionproductsfora1ongtime-Theant(PolyrhachisvicinaRoger)ismostincommon.TheyaremainlylivinginGuangxiProvince.Theyareablack,irri-tateacidityanddelicatefragranceinsects.ThereisakindofantinWandaMountain,Daxing'anMountain,andXiaoxing'anMountain.Itisabig(aboutmorethanl-ocmlong),strongandnonpollutioninsect.alotofbigandblackantswerecollectedfromWandaMountain.Itwasappraisedbyantexpertstobeantfami1yandantcategory.ItwasnamedFormicacuniculariaLa…     

The use of isozyme genetic markers to estimate the rate of outcrossing in a Sitka spruce (Picea sitchensis (Bong.) Carr.) seed orchard in Scotland

Effects of genotype, collection date, auxin treatment, crown position and artificial chilling on rooting and subsequent vegetative growth of Cupressus sempervirens L. softwood cuttings taken from 13-year-old plants were evaluated. Three different clones (318, 296 and 22) previously selected for resistance to cypress cortical cancer caused by Seiridium cardinale were used. In all these clones, both the IBA treated and the untreated cuttings showed seasonal periodicity of rooting. Untreated cuttings rooted best when collected in April (up to 49% for the best clone, i.e. 296) and rooted very poorly in July and October. Auxin treatments appeared unable to overcome this periodicity, as the cuttings taken in July and October did not respond to IBA stimulation. However, in January and April, IBA treatments enhanced adventitious root formation of poorly rooting clones (318 and 22), as well as of clone 296, which performed best (89%) when cuttings were treated in April with 1.5% IBA. Cuttings of each clone collected in the lower third of the crown of the donor trees showed a significantly higher rooting percentage, when compared with those from the upper third. A 4-week post-severance chilling treatment (4°C) significantly enhanced the rooting capacity of cuttings taken in January, while a longer chilling treatment (8 weeks) had a negative effect. The subsequent growth of the rooted cuttings was not affected by either the crown position of the severed cuttings, or the genotype.     

Preparation and Characterization of Phenolated Wood Using Sulfuric Acid as a Catalyst I: Liquefaction Behavior of Plantation Wood

Chinese fir (Cunninghamia lanceolata) and poplar (Populus spp.) wood meal were phenolated in the presence of sulfuric acid used as a catalyst. The effects of reaction time and reaction temperature on the wood liquefaction were investigated. The results showed that the reaction temperature had the greater influence on the residue content than reaction time. Additionally, the liquefaction curve for the Chinese fir and Poplar were similar in general.     

Promotion of the population growth of pinewood nematode in 4-month-old Japanese black pine seedlings by pretreatment with simulated acid rain

Simulated acid rain (SAR) at three pH levels (pH 4, 3, 2) was applied to only the top or both the top and roots of 4-month-old Japanese black pine seedlings repeatedly for two months. Then the seedlings were inoculated with a virulent isolate (S10) of pinewood nematode,Bursaphelenchus xylophilus. The exposure to SAR at any level did not kill the seedlings. When inoculated with nematodes, however, the nematode population build-up was significantly higher in the seedlings pretreated with SAR at any level than in the control at the 7th and 17th day after inoculation, and subsequent disease symptom development was also significantly accelerated by the exposure to SAR at pH 2 and 3. This result indicates that even acid rain at pH 4 has the potential for promoting population growth of pinewood nematodes in 4-month-old Japanese black pine seedlings.     

树木氨基酸组成与光肩星天牛为害程度关系的初步研究

用高效液相色谱，柱前ＯＰＡ衍生法对河北地区的毛白杨、冀秦１号杨、旱柳、加杨、山海关杨、北京杨、大官杨等７种树木的木材研究发现，根据其氨基酸组成可将该７种树木分为３类组合形式：（１）抗光肩是天牛树种──飞白杨，其氨基酸组合中天冬氨酸、丝氨酸、甘氨酸、谷氨酸、苏氨酸、缬氨酸，精氨酸的含量超过平均值；（２）对光肩星天牛敏感树种──山海关杨、北京杨和大官杨，氨基酸组合中该７种氨基酸含量低于平均值；（３）对光肩星天牛较敏感树种──加杨、旱柳和冀秦１号扬，氨基酸组成介于前二者之间。