影响塑料生物降解速度因素的研究

本文对影响塑料生物降解速度的因素进行了研究和讨论，探讨在进行塑料生物降解性试验时提高降解速度、缩短试验时间的可能性。结果表明，在液体中对塑料进行生物降解性试验优于在固体中的试验：碳氮比（Ｃ／Ｎ）、温度和ｐＨ值等对塑料生物降解速度的影响较大；试样的形态对生物降解速度的影响不大；在相同的条件下，分别以土壤、湖水和河水为接种源的培菌液都可对试样进行速度近似的降解。

乡土草坪草生物学特性及繁殖技术研究报告

在银川市中山公园众多的野生草种中 ,我们发现了两种适合当地条件的乡土草坪草———早熟禾和圆囊苔草。通过对这两种草坪草的生物学特性、品质特点、观赏价值的试验观察及繁殖技术的研究 。

生物降解聚酯及其应用

介绍了生物降解聚酯及其应用现状,分析了生物降解的速度控制,指出了开发生物降解材料的必要性以及用生物资源为原料制造生物降解材料是21世纪的发展方向。

壬基酚聚氧乙烯醚(NPEO)在河水的生物降解率测定

壬基酚聚氧乙烯醚(NPEO)是一种应用广泛的非离子表面活性剂,为探讨其在环境中的迁移转移行为,本论文用河水消失法测定其在河水的生物降解性。结果为浓度100mg/L壬基酚聚氧乙烯醚在新开河的生物降解速率为0.0103h-1,半衰期为67h。表明NPEO在河水中是可降解的,且它的生物降解快。

厌氧及二级交互间歇曝气工艺条件下微生物生长动力学特性

在厌氧及二级交互间歇曝气工艺条件(CHBNR,Cui-Hong Biological Nutirents Removal Process)和厌氧-好氧工艺条件下(ASP,Activated Sludge Process)分别确定微生物生长动力学系数,并比较评价了厌氧及二级交互间歇曝气工艺的微生物生长动力学特性.通过试验得出在厌氧及二级交间歇曝气条件下Y(微生物增长系数)、Kd(微生物衰减系数)、K(微生物最大相对增长速度)、Ks(饱和常数)分别为0.200,0.055 d-1,3.12 d-1,38.3 mg/L.厌氧及好氧条件下Y,Kd,K,Ks分别为0.253,0.092 d-1,2.22 d-1,31.7 mg/L.这说明厌氧及二级交互间歇曝气工艺,虽然消耗很多的外部有机物质,但维持自身所需的能源少,相对增长速度小,污泥的生产量少,因而,废弃的污泥量会减少,处理污泥费用降低.

南海文昌海区海生物附着特征分析

海生物附着参数是海上油气田开发前期研究的重要设计参数.论文收集了南海文昌海区7座石油平台的 海生物检测数据,分析了文昌海区附着海生物类型和海生物附着厚度分布.论文通过研究海生物附着厚度的 计算方法以及同时开展的文昌海区海生物附着厚度计算,为海上油气田开发海洋工程设计提供了海生物参数.此外,论文还开展了海生物生长速度的分析,为海上油气田海生物清理周期设计提供参考.

生物处理法辅以投加过氧化物可缩短生物处理时间

引言 随着美国联邦及州的法律日趋严格,对于大约1200处国家急需治理的场所及许多地下污染物储存罐,工业界人士和政府部门都在寻找更加有效,环境更安全以及经济效益更好的污染治理技术。经过多次试验性研究,化学法辅助下的生物治理技术显示出许多优点,并在土壤和地表水治理方面表现出极大的发展潜力。本文扼要综述这一方法的基本原理和特点。

生物降解性聚己内酯聚醚嵌段共聚物及其制备方法

此成果涉及一种具有优良生物相容性,可控生物降解性和药物透过性的新型生物医用高分子材料及其制备方法。具有合成过程简单,所需反应设备简单,产品无毒、在人体内可自行降解。

奶牛营养调控

本文从最佳瘤胃发酵，瘤胃微生物的消化速度，蛋白质、脂肪的调控，阴 -阳离子的平衡，饲养方式等方面论述了奶牛营养调控的措施，从而为奶牛生产提供了理论依据和可操作方法。

31个白灵菇菌株的培养特性及亲缘关系初探

对外引31个白灵菇栽培菌株进行拮抗试验、菌丝生长速度测定、生长势比较、平板出菇试验和栽培试验,比较了它们的培养特征。结果表明:多数栽培菌株为同种异名,但同种异名的菌株培养特性存在显著差异;多数白灵菇菌株容易在平板培养基上形成原基;栽培试验结果表明,31个栽培菌株可以分成柱状、马蹄状和手掌状3大类。

Influence of organic wastes on early growth of tomatoes

We compared the capacity of composts made from three different sources of organic wastes （horse manure and bedding, mink farm wastes, municipal solid waste （MSW） and sewage sludge）, and clarifier solids from a chemo-thermomechanical pulp mill, to enhance the growth of tomato seedlings grown in potting soil with little organic matter. Germination and seedling emergence of tomatoes, cress or radish were tested to assess phytotoxicity of the four amendments. Mink farm compost and horse manurecompost stimulated root and shoot growth of tomato seedlings, but MSW compost and pulp mill solids were strongly inhibitory. MSW compost and non-amended potting soil also inhibited seedling emergence and pulp mill solids produced stunting and deformities in radish and cress seedlings. Both toxic constituents and nutrient imbalances may be responsible for the growth-inhibiting effects of these amendments. Application of pulp mill solids to agricultural soil without composting may lead to deleterious effects on vegetable crops.

Effects of blue light on gametophyte development of Laminaria japonica (Laminariales, Phaeophyta)

Laminaria gametophyte was greatly influenced by light in its growth and development. Using light-emitting diodes (LED) as blue and red light sources, we analyzed the light effect on gametophytes devel- opment of Laminaria japonica Aresch. The gametophytes were obtained from zoospores collected in April, May, July, 2003 and September, 2004. We found that the growth of gametophytes was stimulated by increasing inten- sity of blue light (BL) and red light (RL) illumination, of which BL was obviously stronger than that of RL. The fertilization of gametophytes depended largely on BL, and only sufficient BL illumination could take the repro- ductive effect. In addition, we noticed that there was a significant difference in light responses for gametophytes developed from zoospore collected in different times. For zoospores released in April, under BL1 (73.90 μmol photons/m·s), the unicellular female gametophytes and multi-cellular male gametophytes produced eggs and sperms respectively, and further developed towards sporophytes. However, for gametophytes developed in May, July or September, they became multi-cellular and never formed oogonia or antheridia. It is believed that the Laminaria sporangium maturation stage could affect the gametophytes reaction to BL under laboratory culture conditions. Therefore, cryptochrome- or phototropin-like BL photoreceptors is probably involved in BL-induced development of Laminaria gametophytes.

Rotational nanofluids for oxytactic microorganisms with convective boundary conditions using bivariate spectral quasi-linearization method

In this study,we considered the three-dimensional flow of a rotating viscous,incompressible electrically conducting nanofluid with oxytactic microorganisms and an insulated plate floating in the fluid.Three scenarios were considered in this study.The first case is when the fluid drags the plate,the second is when the plate drags the fluid and the third is when the plate floats on the fluid at the same velocity.The denser microorganisms create the bioconvection as they swim to the top following an oxygen gradient within the fluid.The velocity ratio parameter plays a key role in the dynamics for this flow.Varying the parameter below and above a critical value alters the dynamics of the flow.The Hartmann number,buoyancy ratio and radiation parameter have a reverse effect on the secondary velocity for values of the velocity ratio above and below the critical value.The Hall parameter on the other hand has a reverse effect on the primary velocity for values of velocity ratio above and below the critical value.The bioconvection Rayleigh number decreases the primary velocity.The secondary velocity increases with increasing values of the bioconvection Rayleigh number and is positive for velocity ratio values below 0.5.For values of the velocity ratio parameter above 0.5,the secondary velocity is negative for small values of bioconvection Rayleigh number and as the values increase,the flow is reversed and becomes positive.

The study on the effect of NO on the growth of Chaetoceros curvisetus

This article studied nitric oxide (NO) effect on the growth of Chaetoceros curvisetus in chemistry for the first time. Nitric oxide was added into the media with 4 different nutrient concentrations f/2, f/50, f/100, and f/200 when the alga was growing. The growth of C. curvisetus could be obviously promoted or inhibited during the cultivation process in NO enriched media of different concentrations. The growth curve in such media showed a sharp single peak that is the optimal NO concentration for the alga growth, which is consistent with the influence of NO on the growth of high plants. In addition, C. curvisetus can produce NO by itself during the growth. Therefore, using NO could effectively regulate the algae growth, which is important in real tide control and remediation.

Effects of water temperature and dietary carbohydrate levels on growth and energy budget of juvenile Litopenaeus vannamei

A 3×3 factorial experiment was conducted to determine the effects of water temperature (22 ℃, 27℃ and 32℃) and dietary carbohydrate (CBH) levels (15.47%, 29.15% and 41.00%) on growth, food consumption, feed efficiency, apparent digestibility coefficient and energy budget of juvenile Lito- penaeus vannamei. The results showed that, at each dietary CBH level, specific growth rate, food con- sumption and apparent digestibility coefficient generally increased, while feed efficiency decreased with increasing water temperatures. Specific growth rate and food consumption were the highest in the shrimps fed with diet of 29.15% CBH, closely followed by those with 15.47% CBH, and those with 41.00% CBH had the lowest value.

Biomechanical research of knee joint during the process of running

To study the effect of speed on the biomechanics of a knee joint during running, a biomechanical model of human lower limb joints is established based on the Kane method and semi-physical simulation. Experiments on the running process were made at different speeds for healthy young men. The influence of running speed on knee Joint motion is analyzed quantitatively and a mathematical model of the knee angle is established with speed as the independent variable. Results show that, at the moment of the heel contacting with theground, with the increase of speed, the more, and the calf and thigh are closer to the same line. In the middle stage of a gait cycle, the thigh stretches back, and then the calf and thigh are close to collineation. At that moment, the stretch of the posterior cruciate ligament is the largest, and the slower the speed, the more obvious the collineation. The maximal joint angle of the calf relative to the thigh appears in the later stage, and themaximal joint angle increases with the increase of the velocity. With the increase of the running speed, the phase of the cure of knee angle moves forward. The results can be used in the field of rehabilitation robotics and humanoid robot.

Effect of approach run velocity on the optimal performance of the triple jump

Purpose： The purpose of this study was to determine the effect of horizontal and vertical velocities at the landing of the last step of approach run on the performance and optimal phase ratio of the triple jump. Methods： Three-dimensional kinematic data of 13 elite male triple jumpers were obtained during a competition. Computer simulations were performed using a biomechanical model of the triple jump to determine the longest actual distance using the optimal phase ratio with altered horizontal and vertical velocities at the landing of the last step of approach run. Results： The actual distance obtained using the optimal phase ratio significantly increased as the horizontal velocity at the landing of the last step of approach run increased （p = 0.001） and the corresponding downward vertical velocity decreased （p = 0.001）. Increasing horizontal velocity at the landing of the last step of approach run decreased optimal hop percentage and increased optimal jump percentage （p = 0.001）, while decreasing corresponding downward vertical velocity increased optimal hop percentage and decreased optimal jump percentage （p = 0.001）. Conclusion： The effects of the velocities at the landing of the last step of approach run on the optimal phase ratio were generally small and did not qualitatively alter optimal techniques.

Camptotheca acuminata Decne Residue after Camptothecin Extract as a Substrate to Produce Mushroom Spawn

Currently in China,no technically and economically viable methods exist to handle large quantities of Camptotheca acuminata Decne residue(CA residue) after camptothecin extract while there is a great demand for low cost alternatives to replace the cottonseed hull-based materials used in commercial mushroom culture.Hence,it is of importance for camptothecin extract factories and mushroom producers to explore the utilization of CA residue in mushroom industry.We conducted a research to study how partially or completely substituting traditional mushroom substrate by CA residue would influence the mycelial growth in mushroom spawn production.5 mushroom strains from 4 species were used in the test,i.e.,oyster mushroom(Pleurotus ostreatu) strains,Zayou No.1 and Xide 33,needle mushroom(Flammulina velutipes) strain Chuanjin No.3,hairy wood ear(Auricularia polytricha) strain Huang Er No.10,and shiitake(Lentinula edodes) strain Wuxiang.The nutrient element composition and heavy metal contents of CA residue were determined to ensure its safety and to determine its appropriate component in the substrate formulation for mushroom spawn production.The four substrate formulations(one control-CK,and three treatments,named,T1,T2,T3,) contained 0%,40%,79%,and 100% CA residue,respectively,to allow comparison of the fungal mycelial growth.The control(CK) was the popularly used formulation in Chinese commercial mushroom production,comprising of 73% cottonseed hulls,10% sawdust,15% wheat bran,1% lime,1% white sugar(percentage by weight).All mushroom spawns of the five strains in the four treatments were incubated under the same conditions.The results showed that mycelia of the five mushroom strains grew significantly faster on the substrates containing CA residue than on the substrate with no CA residue(CK).There were no significant differences in the mycelial growth rate among treatments containing CA residue for the two oyster mushrooms and the needle mushroom,but mycelial growth rate in treatments T2 and T3 was significantly higher than in treatment T1 for hairy wood ear and shiitake.The results suggest that CA residue can be used to culture oyster mushroom,needle mushroom,hairy wood ear,and shiitake spawn,and the medium containing CA residue can stimulate their mycelial growth.The commercial production of mushroom spawn using CA residue not only brings better economical benefits including lower cost to mushroom producers,but also reduces environmental pollution by providing a means to reduce dumping and piling of CA residue.

Dynamics of the Currents in the Strait of Khuran in the Persian Gulf

The Strait of Khuran is among the most important marine habitats in the Persian Gulf. It is the location of the largest Avicennia Marina mangroves along the Persian Gulf shoreline and is a major nursery region for the fish and to breeding, wintering and migrant water birds. This paper presents dynamics of the currents in the Strait of Khuran using the current data collected by fixed current meters. The analysis of the data showed that the currents in the Strait of Khuran were highly dominated by tidal forcing with mixed semi diurnal behavior. The tidal currents were strong and reached to a maximum velocity of 123 cm/s in the spring tide. Tidal analysis showed that the tidal current constituents （M2, $2, N2, K1, O1） are dominant with M2 component as the major one. The tidal currents occurred basically along the strait. The results show a westward residual flow along the strait with an average of 5.6 cm/s during the study. The direction of the flow indicates that any pollution discharged into the industrial developing eastern part of the strait has the potential to affect the sensitive ecosystem in the western part.

鲁西北地区冬季栽培平菇菌株比较试验

为筛选适宜鲁西北地区冬季栽培的平菇菌株,于2022年1月至2022年3月选取现有8个供试平菇菌株进行栽培比较试验,考察菌株菌丝生长速度、子实体生物学效率,分析菌丝生长速度与子实体生物学效率间的相关性。结果表明,抗病3号平菇菌株适宜作为鲁西北地区冬季推广栽培菌株,奇美969菌株可作为备选菌株。