共查询到20条相似文献，搜索用时 687 毫秒
1.
2.
自制保鲜剂对灵武长枣低温贮藏保鲜效果的研究 总被引：4，自引：3，他引：1
以可溶性固形物含量24.3%的灵武长枣为试材,研究了冷藏过程中果实品质变化及贮藏保鲜效果。结果表明,保鲜剂浸果极显著降低了霉烂果率,显著减缓了贮藏中后期果肉硬度下降和维生素C氧化分解,明显抑制了果肉蔗糖水解,显著提高了贮藏中后期脆好果率。但保鲜剂浸果对可溶性固形物、还原糖、总糖和果胶含量没有明显影响。脆好果率与果肉硬度、抗坏血酸含量和蔗糖含量均呈极显著正相关性,拟合曲线为二次多项式,相关系数分别为0.9266、0.9937和0.9971。果肉抗坏血酸含量和果肉硬度均与蔗糖含量呈极显著正相关性,相关系数分别为0.9894和0.9343。 相似文献
3.
为探究褪黑素在维持采后梨果实品质方面的潜力,为采后梨贮藏保鲜技术研发提供参考,以成熟期采收的新梨7号梨果实为试材,分别用0(对照),0.02,0.20,1.00 mmol/L的褪黑素溶液浸泡2,4,8,12,24 h后取样,测定了各处理对采后梨果实内在品质、细胞壁裂解相关酶活性、抗氧化相关酶活性及果皮与果肉内源褪黑素和水杨酸含量的影响。结果表明,用0.02,0.20,1.00 mmol/L褪黑素浸泡梨果实8 h,梨果实的硬度分别为38.51,42.79,40.95 N/cm2,乙烯释放速率分别比对照下降了66%,70%,71%;用0.20 mmol/L褪黑素浸泡梨果实8 h,果实的可溶性固形物含量(SSC)为94 g/L,显著高于对照组(80.2 g/L),为对照组的1.17倍,果实的可滴定酸(TAC)为1.013 g/L,也显著高于对照组(0.90 g/L),为对照组的1.13倍;此外,外源褪黑素处理显著提高了采后梨果实超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性,显著降低了采后梨果实多聚半乳糖醛酸酶(PG)、果胶甲酯酶(PME)、... 相似文献
4.
加工番茄果实硬度与相关性状间的分析 总被引：1，自引：0，他引：1
通过对性状的选择和鉴定,运用适当的育种方法,选育出果实硬度高的加工番茄新品系。选用本地品种,对影响加工番茄果实硬度的14个指标与硬度进行相关及通径分析。结果表明：果肉硬度和耐压力与果实硬度呈极显著正相关,其相关系数分别为0.767和0.545;果肉厚度和维生素C含量与果实硬度间呈极显著负相关,其相关系数分别为-0.406和-0.938;可溶性固形物与果实硬度间呈显著负相关,其相关系数为-0.807;其他性状与果实硬度间均不存在显著性。 相似文献
5.
研究采收期对‘黄冠’梨果实品质的影响,旨在揭示‘黄冠’梨果实发育后期果实品质因子的变化规律,为生产中确定‘黄冠’梨的最佳采收期提供理论依据。以‘黄冠’梨为试材,通过测定不同采收期时的单果重、可溶性固形物含量、Vc含量、硬度,并利用液相色谱法测定不同采收期果实的糖酸组成和含量,分析‘黄冠’梨果实发育后期果实品质因子与采收期的关系。结果表明,自果实发育106天开始,随采收期的延后,果实硬度呈显著下降,果实可溶性固形物含量呈上升趋势,并于果实发育137天时达到高峰;Vc含量变化较小,仅在120天时显著较高;在近成熟期采收的果实中糖以果糖为主,占70.09%~84.00%,以果实发育137天时最高;果实中酸以苹果酸为主,苹果酸占酸总量的93.05%~97.28%,苹果酸D占苹果酸的82.92%~91.84%。随采收期的延后,果实发育天数延长,果酸含量下降,采收越晚糖酸比越高。‘黄冠’梨果实发育130~137天时,果实的可溶性固形物、果糖、葡萄糖、蔗糖和Vc含量都较高,糖酸比和果肉硬度适宜,以获得‘黄冠’梨最佳品质为目标的适宜的采收期为8月8—15日。 相似文献
6.
五种秋子梨果实采后品质变化及生理差异研究 总被引：1，自引：0，他引：1
以京白梨、南果梨、花盖梨、尖把梨、安梨5种秋子梨果实为试材,研究其在常温(20±1)℃下果实采后品质变化及生理差异,并分析了果实硬度与其他品质指标的关系。结果表明,供试品种货架期长短存在差异;在后熟过程中,五种秋子梨果实硬度和VC含量均呈下降趋势,可溶性固形物(SSC)含量和相对电导率均呈上升趋势,果皮色泽由绿转黄;京白梨的呼吸强度显著高于其他4种秋子梨(P0.05)且有呼吸跃变峰;京白梨、南果梨、花盖梨及尖把梨的乙烯释放速率均呈先升高后降低的趋势,且均存在乙烯释放跃变,京白梨和南果梨的乙烯释放速率极显著高于其他3种秋子梨(P0.01),安梨没有乙烯跃变峰且乙烯释放速率最低。硬度与其他品质指标的相关性分析表明,除了果实硬度、VC含量、果皮色泽和相对电导率影响秋子梨果实后熟软化外,京白梨的可滴定酸(TA)含量,南果梨的SSC和呼吸强度,以及安梨的SSC均与果实后熟软化呈显著(P0.05)或极显著相关(P0.01)。 相似文献
7.
以丰收560、京采8号、Cap、Saopolo和Jua 5个番茄品种为研究对象,设置了5个采收时期,通过测定可溶性固形物、可滴定酸、可溶性糖含量等品质指标,分析不同品种番茄及采收时期的品质差异性,以期为番茄品质分级提供依据。结果表明:不同番茄品种的品质存在明显差异性,其中Saopolo的可溶性固形物、可溶性糖、可滴定酸、VC含量平均值最高,分别为8.92%、7.35%、0.66%和4.57 mg/g,均显著高于除Jua外的其他品种;丰收560的可溶性固形物、可溶性糖含量平均值最低,分别为3.64%、2.04%;不同采收时期的番茄果实品质存在一定差异性,其中可溶性固形物含量、固酸比、VC含量和a*值等果实品质均存在显著差异,可溶性糖含量、可滴定酸含量、糖酸比、L*值、硬度和感官品质等差异较小。综上,在番茄品质分级时,可将可溶性糖含量、可滴定酸含量、糖酸比、L*值、硬度和感官品质作为分级指标,以减少采收时期对品质分级的影响。 相似文献
8.
为研究不同施肥处理对猕猴桃采后软化的影响,以“东红”猕猴桃为材料,对不同施肥处理的猕猴桃果实在生理成熟期采摘,于室温贮藏,定期取样分析果实硬度、软化率、淀粉质量分数、原果胶质量分数、可溶性果胶质量分数、纤维素质量分数及多聚半乳糖醛酸酶（Polygalacturonase,PG）、果胶甲酯酶 （Pectin methylesterase,PME）、纤维素酶（Cellulase,Cx）、β-半乳糖苷酶（β-D-galaetosidase,β-Gal）、淀粉酶活性的变化。结果表明,合理的施肥处理可延缓果实硬度的下降,减缓果实中淀粉、原果胶、纤维素质量分数的下降,延缓可溶性果胶质量分数及PG、PME、Cx、β-Gal、淀粉酶活性的升高,并推迟峰值出现的时间。不同施肥处理组的果实在贮藏期间其硬度与可溶性果胶质量分数、PG、Cx、β-Gal、淀粉酶活性呈极显著负相关（P＜0.01）,与原果胶、纤维素、淀粉质量分数呈极显著正相关（P＜0.01）。在猕猴桃生产中采用复合化肥+有机肥+生物菌肥相结合的施肥方式可显著延缓贮藏期间果实的软化,延长果实的贮藏期。 相似文献
9.
为探讨冰温贮藏条件对鲜枣品质的影响,以新疆若羌冬枣为试材,将其分别置于0℃冷藏(CK)、-1.5～-1.0℃冰温贮藏,分别测定了贮藏过程中冬枣的失重率、腐烂率、硬度、色差、可溶性固形物含量、果胶含量、多聚半乳糖醛酸酶(PG)、果胶甲酯酶(PME)、β-半乳糖苷酶(β-Gal)活性。结果表明:随着贮藏时间的延长,冰温贮藏枣果失重率的上升、色差的变化程度及可溶性固形物含量的下降均得以延缓;对0℃冷藏的枣果来说,其硬度的下降更快,PG、PME、β-Gal活性也随之升高,而冰温贮藏则抑制酶活性的升高速率,降低枣果实腐烂变质和衰老软化的进程,有效延长若羌冬枣的贮藏期。 相似文献
10.
11.
A power model of a CNC machine tool feed system is proposed based on analyzing the power characteristic of each component in the CNC machine tool feed system. And the tarepower characteristic and its dominant affecting factors are analyzed by using the power model. The analysis results show that the tarepower of feed system is a monotone increasing quadratic function in term of the feed speed. Meanwhile, the feed speed and load mass both affect tarepower, but the influence of load mass is minuteness. Some experiments are conducted on a 3-axis CNC milling and the experimental results justify the theoretical analysis. 相似文献
12.
Considering traditional current protection cannot satisfy the micro-grid, a system protection solution for the micro-grid is proposed. In this solution, the failure message with direction information can be exchanged among the adjacent protection units, so the fault coverage can be determined and the fault can be quickly cleared. By analyzing the movement of the protection in three kinds of fault conditions in the micro-grid that contains three branches and two micro-power based on inverter, the method has been proved that the fault can be quickly cleared and the protection has the same protection strategies for both islanded and grid-connected operation. 相似文献
13.
Belt grinding machine with multi axis computer number control(CNC) system can effectively process parts with complex moulding surfaces.In this paper,iso parametric and iso planar tool path planning strategies customized for this kind of machine are proposed.The tool path generation methods are designed based on the analysis of the belt grinding process.By using least square method,optimized cross section normal is computed in the iso planar method.To improve the design efficiency of path planning,reduce experiments and increase economical benefit,the geometric simulation program based on linear grinding model is developed.Experiment on a turbine blade profile shows that the proposed algorithms work satisfyingly. 相似文献
14.
The governing system of hydraulic turbine generator plays an important role in power system. It is significant to find out the faults of governing system and remove them quickly. This paper sets up a new fault diagnosis model of the hydraulic turbine generator governing system with the advanced ANN (artificial neural net). This 17-in-13-out model consists of three layers. It is proved that this model can find the fault accurately. 相似文献
15.
ZENG Xue hong FAN You ping HAN Rong jun HUANG Xi yue TANG Xian ming MAO Wan biao 《保鲜与加工》2002,(12):49-54
In point of view of the system, the characteristic of leak current fault diagnosis in launch vehicle controlling system is analyzed. It is presented that the fault is a connecting way for sytem factors. By building some basic concepts such as componts, syptoms, observation and faults, the system model is turned into graph, where nodes represent components and edges represent fault transmission among components. Besides,designing rule, that is, bisection rule for diagnosing alglorithm is given based on the information theory. Operating feasibility and entropy function characteristic are analyzed using component trade-off value to substitute component entropy, giving fault problem-solving way based on the drawing model. 相似文献
16.
Many subsystems in CNC machine tool have only a few failures, so they are small samples. In this case, classical reliability modeling method often has large errors. For the failure data of small sample, maximum likelihood estimation method is used to estimate the Weibull distribution model parameters of time between failures of the subsystems. Then, the Weibull distribution model parameters are modified by parameter bias correction method. Finally, the effect of bias correction parametersis tested by the D test and the error area ratio test method. The test results show that the modified models are better. 相似文献
17.
This paper discuses the method with which the corrosion of the grounding grid can be diagnosed .A grounding grid can handled as a circuit network. With the application of circuit network graph theory and the fault diagnosis theory of analog circuit and optimization, the fault diagnosis equations can be set up. This equations is figured out by Matlab, and the corrosion status of the grounding grid can be deduced from the result. 相似文献
18.
TANG Xian? ming FAN You? ping MAO Wan? biao HANG Rong? jun ZENG Xue? hong HUANG Xi? yue 《保鲜与加工》2003,(1):28-33
A visualized analysis system of leak current fault transmission graph is developed. Its functions, program structure and programming principle are described.The system is composed of fault diagnosing module and man machine exchanging module, which make the generation and analysis of leak current fault transmission graph for lauch vehicle controlling system simple and visualized. The system could automatically recognize the picture of transmission and analyze both qualitatively and quantitatively only by drawing it on the monitor by the mouse. Finally an example is given, where a satisfying result is acquired via drawing inputting method which is totally new and expanding-complementing the fault tree alglorithm. 相似文献
19.
阿特拉津作为除草剂大面积使用，在提高作物产量的同时，对土壤、地下水和江河湖泊等环境造成了污染。虽然阿特拉津的毒性较低，但其易溶于水、难降解、残留较大，影响作物产量，牵制中国农业的可持续发展。文章对阿特拉津残留量过大时对当地动植物造成的危害，对生态环境产生的威胁，以及对人类健康产生的影响展开综述。报告了阿特拉津的吸附机理与残留原因，阐述了其对动植物产生的影响，将现有的阿特拉津降解方式进行比较和分析，并对阿特拉津降解的未来趋势进行讨论和展望。为解决生物修复技术周期长等问题，结合不同降解方式提出了建设性的意见和建议。将物理修复技术、生物修复技术、化学修复技术相结合，可以找出对阿特拉津残留降解效果最好、有利于当今可持续发展理念的修复技术。 相似文献
20.
Yin Yousheng Liang Xichang Huang Daixing Liu Hengxue 《保鲜与加工》1993,(1):32-36
To subgrade the shape-curve roughness of a contact roller,the three-coordinate CNC milling machine has been enlarged as a CNC lathe and CNC grinding machine so that the contact rollers can be lathed and grinded by the same installation and NC program. Furthermore,an NC program of dealing with complex curve contact rollers has been developed. Acceptable metal shaving contact rollers of cycloidal gears and involute gears in shape grinding have been manufactured with this method. 相似文献