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71.
对连续15 a福建省脂松香生产企业的质量抽检调查及统计分析结果表明,各个级别脂松香质量的各项主要技术指标均优于目前的国家标准(GB/T 8145—2003)要求,但仍存在影响脂松香质量的问题。要通过实施松香全过程质量控制,并加快品牌创建,不断满足市场对产品质量的多样化要求,以提高松香产品质量与效益。  相似文献   
72.
黄秋葵食用胶的制备及应用研究进展   总被引:1,自引:0,他引:1  
董彩文  刘长虹 《安徽农业科学》2008,36(13):5687-5688
介绍了黄秋葵食用胶的组成、基本特性、制备及其在食品工业中和其他工业中的应用。  相似文献   
73.
This study (3 × 2 randomized factorial design) describes differences in the mechanical properties of faeces from rainbow trout of three size classes (small ≈40 g, mid-size ≈150 g, large ≈650 g) and assesses the effects of a non-starch polysaccharide binder (guar gum). Observations made at the macroscopic level were reinforced by rheological measurements of viscosity and elastic modulus. Mid-sized fish excreted mechanically the most stable faeces, roughly twice as stable as those of small fish and three times more stable than faeces from large fish. The addition of 3 g kg−1 of guar gum saw some mechanical characteristics improve by about 700%. Faeces from large- and mid-sized fish were more easily stabilized than those of small fish. Mechanical recovery potential for faecal samples disrupted by water turbulence was determined. Stability differences observed for different fish size had no significant effect but the improvements imparted by guar gum reduced postfiltration effluent load to about 35% for large fish, about 24% for mid-size and about 22% for small fish. Faecal leaching decreased significantly with increasing stability. Guar gum was shown to have significant potential for improving the treatability of fish faecal waste.  相似文献   
74.
75.
利用简洁的工序,探索巨桉仿黑胡桃的染色工艺.结果表明:对0.65 mm厚的巨桉薄木染色,薄木不经漂白处理,添加研制的渗透剂W X 3,可直接染成黑胡桃色,染透仅需45 m in,染液总质量分数不大于0.3‰,并且可以连续利用3次;巨桉早晚材上色不一,经处理后材质纹理清晰,可以直接用于仿黑胡桃薄木贴面.  相似文献   
76.
In order to study and monitor rates of rooting, callusing and survival, small diameter stem cuttings (less than 0.4 cm) with eight nodes (12–14 cm long) were taken from trees in the field at different times of the year in tests with small batches of cuttings. Among the four tested substrates, well drained crushed basalt powder placed on a bed of gravel was the best rooting medium. Rooting was generally poor or even non-existent with this type of cutting, but the presence of leaves both promoted rooting and significantly (using Chi square test) improved survival of the cutting. Four leaves were sufficient to assure the necessary metabolic functions. Only stem cuttings collected during the rainy season gave roots and then, only when hormonal treatments were applied to the cuttings. 8%-IBA resulted in significantly better rooting than did 2%-IBA, 0.2%-NAA and 1%-IAA. With 8%-IBA, the rate of rooting varied between 50 and 70% for leafy cuttings collected in the rainy season. Hormonal treatments had a significant effect on the survival rate of the stem cuttings during the two months observation period. Further investigations are being conducted with different types of cuttings.  相似文献   
77.
本试验旨在研究对比添加0.3%的瓜尔豆胶饲料(DJ)及普通饲料(PT)在推水养殖模式下的氮磷收支和养殖效果。试验期为120 d。结果表明,在推水养殖模式下,两种饲料对鱼类生长均无显著影响。且添加瓜尔豆胶还能减少氮磷排放量,减轻对养殖水体的污染。对比两个池塘,在氮磷输入方面,饲料是主要来源,PT输入氮286.88 kg、输入磷74.25 kg,分别占总输入的76.0%、88%;DJ输入氮290.94 kg、输入磷86.41 kg,分别占总输入的74%、88%。PT通过鱼输入氮87.0 kg、输入磷8.38 kg,分别占总输入的23%、10%;DJ通过鱼输出氮96.8 kg、输入磷7.36 kg,分别占总输入的25%、8%。而在氮磷输出方面,PT吸排污输出氮141.5 kg、输出磷47.35 kg,分别占总输出的40%和60%。DJ吸排污输出氮189.57 kg、输出磷63.13 kg,分别占总输出的60%和76%,在吸排污方面,两组之间差异显著(P <0.05)。可以看出添加瓜尔豆胶后会明显改善饲料及肠道排泄物在水中的稳定性,降低对环境的污染。试验结束后通过肠道切片观察养殖周期投喂饲料对肠道组织是否有影响。通过观察饲料对肠道的损伤情况,可以看出,喂食两种饲料的鱼肠道均呈现完好状态,前肠绒毛形状完整,整齐地伸入肠腔内,未发现绒毛破损、肿胀、脱落、表皮细胞水肿充血等症状。  相似文献   
78.
气相色谱-质谱法分析蜂胶和杨树胶的化学成分   总被引:6,自引:1,他引:6  
利用GC-MS分析方法分别对蜂胶和杨树胶进行了分离鉴定,两种物质各鉴定出80多种化合物。蜂胶中芳香酸、醇及酯类物质明显高于杨树胶中的含量,杨树胶中总黄酮和萜烯类化合物的含量略高于蜂胶中总黄酮和萜烯类化合物的含量。另外,可以初步确定苯甲醇、3,4-甲氧基肉桂酸、3-苯基-2,3-二甲基环丙烯、2,6-二羟基-4-甲氧基查耳酮和柯因等几种物质在蜂胶和杨树胶中的含量有较大的差异。因此,可以把它们作为蜂胶中的标志性物质进行检测、辨别。  相似文献   
79.
Pathological tissues from a variety of plants turn red when treated with the histochemical reagent phloroglucinol (PG)–HCl. This induced PG–HCl reacting material has been termed both wound gum and, more recently, induced lignin or lignin-like material. We are exploring alternative approaches to better identify this induced material. In this report, we describe methods for purifying the PG–HCl reactive material from solvent-washed tissue preparations and measuring the amount of p -coumaryl aldehyde released from the purified material by boiling in water. Acorn squash fruit wall tissue was sliced, sprayed with pectinase to elicit the formation of PG–HCl reactive material and incubated up to 72 h at 27°C. Sampled tissue was washed extensively with water and organic solvents. Insoluble residues were treated with cell wall degrading enzymes to remove cell wall materials, and dimethyl sulfoxide was used to dissolve starch. Yields of residual material increased from 7.5% in the time zero samples to 29.7% after 72 h. Refluxing the purified material in water released <6 μ g p -coumaryl aldehyde g−1 from preparations of tissue at time zero and 8100 μ g p -coumaryl aldehyde g−1 from samples incubated for 48 h. These results suggest that the function of the material is to sequester phytoalexins, but are not consistent with the material being lignin. Published by Elsevier Science Ltd.  相似文献   
80.
亚麻胶提取工艺的研究   总被引:1,自引:0,他引:1  
以亚麻籽为原料,利用浸提工艺和喷雾干燥工艺制备亚麻胶的过程,分别考察了提取温度、浸提时间、洗胶次数、总料液比对提取率的影响,并通过单因素和正交试验确定了亚麻胶最佳提取工艺条件:洗胶次数为4次、浸提温度为80℃、浸提时间为1 h、总料液比为1∶4,该条件下亚麻胶的量可达8.307 g.  相似文献   
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