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1.
影响冻干制品残余水分的因素很多,但西林瓶胶塞的含水量是其关键因素。使用经干烤工艺处理和未干烤处理的药用溴丁基胶塞进行麻疹减毒活疫苗冻干试验,结果显示,用未经干烤工艺处理及处理的药用溴丁基胶塞冻干的麻疹减毒活疫苗,存储18个月后,水分上升的平均值分别为2.03%和0.08%,经单一因素的方差分析,两者有统计学意义(P0.01)。证明经处理的药用溴丁基胶塞,对保持麻疹减毒活疫苗在存储期内的残余水分稳定作用效果明显。  相似文献   

2.
J C May  R M Wheeler  E Grim 《Cryobiology》1989,26(3):277-284
The gravimetric test for the determination of residual moisture in freeze-dried biological products performed in a humidity- and temperature-controlled room with the use of scrupulous gravimetric analytical technique can be used to accurately determine residual moisture in freeze-dried biological products such as antihemophilic factor (human) or honey bee venom allergenic extract. This method determines the first water of hydration of sodium tartrate dihydrate (7.93%) to within 1.3% of the calculated value with a relative standard deviation of 0.3% for 10 replicates. For this gravimetric procedure, freeze-dried samples containing from 1.12 to 4.4% residual moisture had relative standard deviations ranging from 3.6 to 9.1%. Samples containing less than 1.0% residual moisture by the gravimetric method such as intravenous immune globulin and antihemophilic factor (human) had relative standard deviations ranging from 16.7 to 47.0%. Relative standard deviations for residual moisture tests performed on comparable samples by the Karl Fischer and thermogravimetric methods showed similar variability.  相似文献   

3.
Awuah RT  Ellis WO 《Mycopathologia》2002,154(1):29-36
Powders from the leaves of Ocimum gratissimum and cloves of Syzygium aromaticum were used as protectants at 3% (w/w) in combination with various packaging methods to store 3.5 kg groundnut kernel samples (9.3% moisture) artificially inoculated with Aspergillus parasiticus. Phostoxin-protected and unprotected samples were the controls. Packaging was accomplished with (i) Jute bags; JB (ii) Interlaced polypropylene bags; IPPB (iii) Polyethylene bags; PB (iv) PB inserted into IPPB and (v) PB inserted into JB. Selected treatments were repeated concurrently with naturally infected kernels (6.6% moisture). With 9.3% moisture kernels, there was a highly significant protectant, packaging method, and protectant X packaging method effect on protection of kernels from fungal infection at 2, 4, and 6 months. Packaging with JB and IPPB with or without plant powders gave 100% protection against fungi but insect infestation was prevented only when the Syzygium powder was used. When PB was used either singly or in combination with JB and IPPB, 100% protection from fungi was achieved up to 2 months with the Ocimum and up to 4 months with the Syzygium powder. The phostoxin treatment also gave 100% protection with JB and IPPB packaging but was ineffective with PB packaging. Kernels packaged with PB without the powders were extensively mouldy. Kernels with natural mycoflora (6.6% moisture) were free from fungi at 6 months regardless of the protectant and packaging used. In further tests, the Syzygium powder, at 3% and in combination with JB-packaging, effectively suppressed cross infection of healthy kernels (12% moisture) by fungi from diseased kernels when both kernel types occurred in the same lot. At 18.5% kernel moisture and with identical packaging, the Syzygium powder at 3%, was not as effective. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

4.
张慧杰  竹长青 《蛛形学报》1994,3(2):100-103
试验结果表明,除含水量为5%和17.5%的土壤外,无视异绒螨在含水量为7.5%~15%的范围内均可产卵,其中以含水量为12.5%的土壤产卵量最高,与其它土样之间存在着显著性差异。根据聚类分析结果,可将供试的土样分为3个类型,即最适产卵型(土壤含水量为12.5%)、适宜产卵型(土壤水量为7.5%~10%)和不宜产卵型(土壤含水量为5%、15%和17.5%)。  相似文献   

5.
This report describes a unit employed for the freeze drying of histocompatibility typing serum using a 50-hr cycle. This unit will process approximately 3200 3-ml vials with a final residual moisture content of less than 2%. The system employs dry ice-alcohol cooled circulating baths to maintain the condensers below ?60 °C, and two shelf cooling baths to maintain the product at required temperatures during the freeze drying process.The results of a 5-yr study of the effect of residual moisture as a function of time and storage temperature is also included. Studies conducted to date indicate that with residual moistures below 2%, freeze dried histocompatibility sera can be stored at +4 °C without the loss of significant tissue typing factors. Solubility of all serum was lost when stored at +37 °C or higher during this same 5-year period.  相似文献   

6.
Forty varieties of vegetable, cereal, fodder and grass seeds at 10, 13 and 16% moisture content were fumigated with methyl bromide at 10 and 18oC, to determine the maximum safe moisture content required to avoid unacceptable phytotoxicity. Dosages (concentration x time products) of 200 and 400 mg h/1 of technical and commercial methyl bromide were used and treated seeds were compared with controls in germination tests. Results were not consistent, but in c. 30 % of the comparisons lower moisture contents, lower temperature and lower dosage each resulted in better germination than the corresponding higher values. The reductions in germination of treated samples were usually less than 5 % and the overall average reduction was only 2.3%. This work showed that under controlled conditions the treatments are safe for most of the tested varieties of seed, but for some seeds, particularly white clovers, Agrostis and runner beans, the highest moisture content (16%) should be avoided.  相似文献   

7.
Peracetic acid-ethanol sterilization (PES) with a preceding delipidation step is an effective sterilization method for allograft bone, but its influence on biomechanical properties of bone has not been studied. The aim of this study was to evaluate the effects of different incubation times of water, hydrogen peroxide and alcohol cleansing procedures combined with PES on biomechanical properties of freeze-dried cortical bone. These effects were studied by performing three-point bending tests on cortical samples. The lyophilized cortical samples were rehydrated prior to mechanical testing. The bending strength and the absorbed energy of the processed cortical samples were increased slightly but the Young's modulus was decreased compared to unprocessed samples. However, when the residual moisture content of the processed cortical samples was reduced from <5% to 0% all the biomechanical properties studied were significantly decreased. Hexane elution was used to determine the residual fat content of the processed cortical bone. Reducing the incubation time in cleansing had no effect on the residual fat content of the bone samples. Our in vitro study indicates that the cleansing procedure proposed combined with PES affects the biomechanical properties of cortical bone only on a limited scale.  相似文献   

8.
Composting winery waste: sludges and grape stalks   总被引:8,自引:0,他引:8  
The composting of winery waste is an alternative to the traditional disposal of residues, and also involves a commitment to reducing the production of waste products. We studied two residues (sludge and grape stalks), mixed in two proportions (1:1 and 1:2 sludge and grape stalks (v/v)), and we also examined the effects of grinding the grape stalks. Our results showed that composting the assayed materials was possible. Best results were obtained in the compost heap in which the residues were mixed in the proportion 1:2, and where the grape stalks had been previously ground. Optimum results required a moisture around 55% and a maximum temperature around 65 degrees C and an oxygen concentration not lower than 5-10%. The resulting compost had a high agronomic value and is particularly suitable for the soils of the vineyards which have a very low organic matter content. The compost can be reintroduced into the production system, thereby closing the residual material cycle.  相似文献   

9.
Abstract  The potential of spinosad as a grain protectant for the lesser grain borer, Rhyzopertha dominica , was investigated in a silo-scale trial on wheat stored in Victoria, Australia. Rhyzopertha dominica is a serious pest of stored grain, and its resistance to protectants and the fumigant phosphine is becoming more common. This trial follows earlier laboratory research showing that spinosad may be a useful pest management option for this species. Wheat (300 t) from the 2005 harvest was treated with spinosad 0.96 mg/kg plus chlorpyrifos-methyl 10 mg/kg in March 2006, and samples were collected at intervals during 7.5 month storage to determine efficacy and residues in wheat and milling fractions. Chlorpyrifos-methyl is already registered in Australia for control of several other pest species, and its low potency against R. dominica was confirmed in laboratory-treated wheat. Grain moisture content was stable at about 10%, but grain temperature ranged from 29.3°C in March to 14.0°C in August. Bioassays of all treated wheat samples over 7.5 months resulted in 100% adult mortality after 2 weeks exposure and no live progeny were produced. In addition, no live grain insects were detected during outload sampling after a 9 month storage. Spinosad and chlorpyrifos-methyl residues tended to decline during storage, and residues were higher in the bran layer than in either wholemeal or white flour. This field trial confirmed that spinosad was effective as a grain protectant targeting R. dominica .  相似文献   

10.
Aqueous solutions of the carbohydrates alpha alpha'-trehalose, mannitol and lactose, human serum and human albumin were freeze-dried in ampoules and part of each batch was further desiccated over phosphorus pentoxide in a manner similar to that used to prepare international biological standards and related materials. The residual moisture present in the preparations and their uptake of moisture was then measured by Karl Fischer titration. In ampoules open to atmosphere [22 degrees C, 34% relative humidity (RH)] freeze-dried serum, albumin, lactose and alpha alpha'-trehalose all exhibited hygroscopic properties, their moisture contents rising over a period of 24 h, to 10%, 8%, 8% and 7%, respectively. Mannitol when dried to low moisture levels did not exhibit hygroscopic properties, but the residual moisture in different freeze-dried batches was very variable, possibly as a result of that solid's sponge-like and/or crystalline microstructure. When exposed to the same conditions, dried materials in ampoules fitted with polythene capillary leak plugs (used routinely at this Institute during the preparation of Biological Standards) exhibited a considerably reduced rate of moisture uptake. The effect of secondary vacuum drying over phosphorus pentoxide on the moisture content of these preparations is also reported.  相似文献   

11.
Thermoplastic starch was prepared by mixing native high amylose potato starch and normal potato starch in a Buss co-kneading extruder at starch to glycerol ratios of 100:45 and 100:30. The materials were also conditioned to different moisture contents at different relative humidities at 23 °C. After the mixing, the compounds were extruded into sheets with a Brabender laboratory extruder. The thermoplastic high amylose materials exhibited a higher melt viscosity than the normal potato starch materials when conditioned at 53% relative humidity. Increasing the moisture content in HAP from 27% to 30% (by weight) lowered the melt viscosity to the same level as that of normal potato starch with a moisture content of 28%. In general, the high amylose materials were more difficult to extrude than the thermoplastic material based on normal starch. The main extrusion problems encountered with the high amylose starch were unstable flow, insufficient melt tenacity and clogging of the die. By increasing the moisture content, increasing the compression ratio of the screw and increasing the rotation rate of the screw, the problems were reduced or eliminated. However, only with a starch to glycerol ratio of 100:45 was an acceptable extrusion result obtained. Extruded sheets of such high amylose materials had a stress at break of about 5 MPa at room temperature and 53% relative humidity, whereas the corresponding value for normal potato (thermoplastic) starch was 3 MPa. The elongation at break was also higher in the case of the high amylose material. The results are discussed in terms of residual crystallinity of the starch materials.  相似文献   

12.
《Journal of Asia》2000,3(2):113-119
Effect of Sitophilus zeamais Mostschulsky infestation on the heat changes of maize at 13, 16, and 19% moisture content with 0, 5, and 10% broken corn and foreign material was studied in 1.81 thermos containers. Containers with infested and uninfested maize were held in a chamber at 26.6°C and 60±5% r.h. for 80 d. Temperatures were measured continuously using a datalogger system. At 13 and 16% moisture content, more grain heating was recorded in infested than in uninfested maize. Presence of insects and moisture content level were major factors in grain heating during storage. Level of BCFM did not significantly affect the grain heating. At 19% moisture content, grain heating increased in all treatments. Heating appeared to be more related to microbial growth than to insect activity, and accumulated to 26.5–37 kj/kg maize at 3–4 wk. The growth of the maize weevil population was significantly affected by grain moisture content. The greatest number of offspring after 80 d was recorded in the 13% moisture content trial. At 19% moisture content, there were more dead than live insects.  相似文献   

13.
Suspensions of influenza virus were dried by sublimation of ice in vacuo to contents of residual moisture of 2.8, 1.6, or 0.6%. After drying, the preparations were sealed under helium, argon, nitrogen, or a mixture of oxygen and nitrogen (30% O(2), 70% N(2)). Stabilities of the several preparations were determined by an accelerated storage test. Based on the times predicted for the dried preparations stored at preselected temperatures to lose 1 log of infectivity titer, the order of stabilities in relation to residual moisture, gas was as follows: 1.6%, He > 0.6%, He > 2.8%, He > 1.6%, Ar > 2.8%, N(2) > 2.8%, Ar > 1.6%, N(2) > 2.8%, O(2) > 0.6%, Ar > 0.6%, N(2) > 1.6%, O(2) > 0.6%, O(2). The stability of the preparation sealed under helium and dried to the content of residual moisture found best for this gas (1.6%) resulted in an increased stability of the order of years as compared to the other preparations tested.  相似文献   

14.
The freshly harvested mature neem seeds (42.2 % seed moisture content) with 100 % viability deteriorate when naturally desiccated to below 10.9 %. The desiccation-induced loss of viability was closely associated with over accumulation of superoxide anion and lipid peroxidation products both in the embryonic axes and cotyledons. The levels of superoxide anion and lipid peroxidation products were higher in axes compared to cotyledons. Superoxide dismutase activity was not much affected, both in the axes and cotyledons of 100 % viable seeds during desiccation from 42.2 % to 10.9 % seed moisture content. Steep rise in its activity was observed during drying below lowest safe moisture content (LSMC). Activities of catalase and peroxidase exhibited substantially higher levels in the 100 % viable seeds dehydrated up to LSMC. Their activities declined sharply in seeds with water content below LSMC. Impairment of catalase and peroxidase activities possibly lead to enhanced accumulation of reactive oxygen species. The accumulation of superoxide anion, lipid peroxidation and differential expression of superoxide dismutase and catalse/peroxidase activities in response to desiccation (below LSMC) is discussed to explain the intermediate storage physiology of neem seeds.  相似文献   

15.
Investigations of the temperature tolerances of Metarhizium flavoviride conidia, of different moisture contents, in an oil formulation were carried out. The conidia were dried to 5, 9, 15 or 19% moisture contents and exposed to a range of temperatures, -15, 12, 25, 38, 48 and 55 C. Viability declined due to high temperatures and high moisture contents. After 4 months of storage, the conidia were at over 80% viability in all but the 19% moisture content group of the 25 C treatment and all the samples stored at lower temperatures. In a second experiment, conidia dried to 4-5% moisture content showed greater temperature tolerance than conidia with higher moisture contents. Short-term storage under adverse conditions could be feasible with conidia dried to a suitable degree.  相似文献   

16.
AMIN NIKPAY 《Insect Science》2006,13(6):421-429
Diatomaceous earth (DE) is a natural inert dust used to control insect pests in stored grain as an alternative to synthetic residual insecticides. Various DE formulations are now registered as a grain protectant or for structural treatment in many different countries throughout the world. The mode of action of DE is through the absorption of cuticular waxes in the insect cuticle, and insect death occurs from desiccation. The main advantages of using DE are its low mammalian toxicity and its stability. The main limitations to widespread commercial use of DE are reduction of the bulk density and flowability of grain, irritant hazards during application and reduction in efficacy at high moisture contents. This paper is an updated review of published results of researches related to the use of DEs and discusses their potential use in large-scale, commercial storage and in small scale applications.  相似文献   

17.
影响生物制品冻干粉针剂水分的探讨   总被引:3,自引:0,他引:3  
探讨生物制品冻干粉针剂样品放置一时间后残余水分增高的原因。进行了水分测定,真空度检测,二甲硅油和丁基橡胶药用瓶塞干燥失重的检测。冻干后每只丁基橡胶药用瓶塞平均含水分0.00224g。结果表明丁基橡胶药用瓶塞灭苗,干燥和冻干过程中去除水分不彻底是引起样品中水分升高的直接原因。  相似文献   

18.
Desiccation studies in relation to the storage of Araucaria seed   总被引:1,自引:0,他引:1  
Relationships between seed moisture content (fresh weight basis) and germination were examined for nine Araucaria species by desiccation under mild environmental conditions. The lowest safe moisture content, below which germination percentage begins to decline, was estimated in each case. Seeds can be grouped into three moisture content categories: the first group (including A. araucana, A. angustifolia, A. hunsteinii and A. bidwillii) cannot be safely dried to below 25–40%; the second group (including A. columnaris, A. rulei, A. nemorosa and A. scopulorum) cannot be dried to below about 12% without damage; the third category contains A. cunninghamii, which can be dried to 2% without damage. Seeds in the first group should be stored at 0–5 °C with moisture contents above the lowest-safe value. Provided freezing damage does not exceed 10%, seeds in the second group should be kept at - 18°C or lower with about 7% moisture content for long-term storage and at 0–5 °C with about 12% moisture content in the short term. Seed of A. cunninghamii is best retained at near 5% moisture content and in -18°C or lower. The lowest-safe moisture content was found to be associated with seed size and weight, higher moisture content values coinciding with greater size and weight of seed. Food reserve materials also differed among the groups; seeds of the first group were mainly starchy, whilst those in the other categories possessed a high lipid content.  相似文献   

19.
The effect of the treatment of barley straw with urea (6% of the D.M.) on its chemical composition, digestibility, degradability and nitrogen fractions was studied varying the initial straw-treatment moisture level (20%, 30% and 40%) and storage temperature (25°C and 35°C). The urea treatment fundamentally affected the NDF content of the straw, which decreased as a result of hemicellulose solubilization. The decrease in NDF was greatest when the initial temperature and moisture content of the straw were both high, under which conditions the maximum solubilization of hemicellulose (25%) occurred. In vitro digestibility and degradability also improved with the urea treatment. In this regard, the greatest improvement (up to 20 points in the case of the digestibility results) was seen when hemicellulose solubilization was maximum. The amount of nitrogen retained by the straw (after deducting the residual urea) rose under conditions of increased moisture and temperature, reaching its highest values at moisture levels of 35% and 40%, when the best urea hydrolysis also took place.  相似文献   

20.
The endoparasitic nematophagous fungus, Esteya vermicola, has potential as a biocontrol agent against pinewood nematode, Bursaphelenchus xylophilus. An E. vermicola conidial formulation was developed to improve conidial resistance to ultraviolet (UV), drought and heat stress. The effective concentration of each protective additive [UV protectant [fulvic acid (FA) and skim milk (SM)]; drought protectant (sorbitol) and heat protectant (calcium chloride)] was determined based on the germination rate of E. vermicola conidia after exposure to the different stressors. A combination of 0.2% FA and 4% SM, 5% sorbitol and 0.05% calcium chloride provided the most effective protection. In addition, the concentrations of spreader–sticker and antibiotic were also decided. The final formulation could be used to improve the resistance of E. vermicola conidia to multiple stressors and to increase nematode mortality compared with unformulated conidia.  相似文献   

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