品牌认证对果农线上销售的影响研究——基于线性回归与PSM方法

基于江西省379份果农的实地调研数据,运用线性回归和倾向得分匹配法检验了品牌认证对果农线上销售的影响。结果表明:①获得“三品一标”认证和注册农产品商标对线上销售均具有显著正向影响,但注册农产品商标的影响效果更明显。②电商经验、鲜果经营培训、品牌建设支持和当地快递公司数对线上销售呈正向影响,而果农年龄和果园距最近快递集散点的距离抑制了线上销售比例的提升。基于研究结论,提出政府应积极引导果农进行品牌认证,加强认证后的监督管理,提高果农品牌保护意识,鼓励果农积极主动注册农产品商标,促使果农线上销售显著提升。     

纳米技术及材料在环境保护中的应用

概述了纳米技术及材料在环境保护中的应用情况,特别是在污水处理与空气净化方面,认为纳米技术及材料的应用将会给环境科学带来突破性进展,为彻底改善环境和从源头上控制新的污染源的产生创造条件,表明利用纳米技术及纳米材料解决环境污染问题将成为未来环境保护发展的必然趋势。     

Transport of fish from Norway: energy analysis using industrial ecology as the framework

In this article, industrial ecology is used as a framework for analysing transport energy and its implication for products. The importance of the energy use for transport in a natural resource production system is analysed. By using fish as a case study, it is shown that the amount of energy for transport is highly dependent on the transport mode used. When applying industrial ecology principles for making assessments of the environmental impacts of products, the whole product chain is examined. This is an extended life-cycle approach, which also includes the transport of the finished products from the exporter to the importing country. This last part of the transport chain can be extremely energy demanding, as is shown for the case of fish transport. This finding has implications for the products, and for the form in which the products should be transported. Increasing the energy efficiency of production systems is an important industrial ecology principle, and must be taken into consideration when analysing product chains. A revision of today's practice of transporting large quantities of fresh whole fish by transcontinental airliners is bound to be necessary. This is a consequence of the demands for increased energy efficiency of tomorrow's industrial production systems.     

Production supervisor impacts on subordinates' safety outcomes: an investigation of leader-member exchange and safety communication

PROBLEM: Supervisors are increasingly important to the functioning of manufacturing operations, in large part due to their role as leaders. While supervisors' relations and communication with their subordinates are known to be important in influencing subordinates' behavior, little is known about how these two factors will impact subordinates' safety. This study investigated how much each factor contributes to safety-related outcomes for blue-collar production employees. METHOD: Production employees at five Pennsylvania wood manufacturers completed a survey during their work shift. Five hundred and ninety eight employees provided data on leader-member exchange (LMX), safety communication, and safety-related events. Archival data on OSHA recordables were also obtained from the producers' human resources database. RESULTS: Analyses found that the influence of LMX was greater than that of safety communication in predicting safety-related events. Neither LMX nor safety communication was significantly related to OSHA recordables. Results also demonstrated that employee job satisfaction and demographic variables such as gender and age have safety implications. IMPACT ON INDUSTRY: Results from this study further emphasize the importance of production supervisors and illustrate the potential role of leader-member exchange in enhancing workplace safety. Specifically, organizations should foster positive social exchange between their employees and supervisors and enhance the leadership qualities of supervisors to help reduce workplace injuries.     

Simplification of Pine Forests Due to Utilization by Tibetan Villages in Southwest China

In China, many rural communities depend upon forests to provide wood, fuel, fertilizer, animal bedding, and valuable non-timber forest products (NTFP). However, the degree to which forest resource extraction is compatible with new conservation aims is unclear because there is little information on the specific ecological effects of traditional forest collecting practices. Therefore, we compared the structure and floristics of Pinus densata forests exposed to three levels of resource extraction by Tibetan villages in northwest Yunnan: (1) a forest site protected from wood and timber removal, (2) moderately utilized forest sites exposed to traditional collecting practices, and (3) patches of highly utilized forest from which timber extraction is high in response to recent development pressures. The results show that understorey and cryptogamic species are reduced in all the utilized forest sites by comparison with the protected forest. However, the moderately utilized pine forests still provide good NTFP habitats by maintaining relatively high canopy covers, litter covers, and understorey structural complexity; this suggests that traditional forest resource use, while simplifying the forest, does not pose an increasing threat to pine forest integrity. By comparison, the highly utilized forests are transformed into open, herb-rich environments in which canopy covers and understorey complexity are depleted, and NTFP habitats are degraded. In the future it may be practical to enhance biodiversity by proscribing forest resource collection, but the immediate priority is to monitor the sustainability of forest utilization using indicators such as understorey development, litter cover, and cryptogamic richness.     

短短芽胞杆菌及其芽胞对芘的降解

考察短短芽胞杆菌(Brevibacillus brevis)菌体及芽胞对四环多环芳烃芘的降解性能.结果表明,菌体5 d内对1 mg·L-1芘的降解率可达53%.菌体和胞内酶降解芘过程中检测到1-羟基芘、9-羟基菲、α-萘酚和β-萘酚这4种单羟基降解产物,在完整菌体降解体系中,产物呈现先积累后下降的趋势,而在胞内粗酶液降解体系中,大分子代谢产物表现为一直积累的趋势,说明B.brevis完整菌体在降解初期并不具备一些中间产物的降解酶,但随着时间推移,可被诱导产生相关酶对生成的新产物进行进一步降解.芽胞悬液在添加芘的无机盐培养基中5 d内萌发生成的营养细胞可达到1.5×109个·L-1,对1 mg·L-1芘的降解率达到15%.     

油品脱酸工艺研究进展

综述了国内外油品脱酸技术发展历程和研究现状,分析了各种技术工艺的优点和不足,随着环保、节能减排思想的深入,新的绿色脱酸分离技术将是以后发展的主要趋势。     

全氟辛酸(PFOA)厌氧生物可降解性

全氟辛酸(PFOA)的可生物降解性对阐明其环境归趋具有重要意义.根据前人的还原降解研究成果,采用PFOA摩尔回收率、氟离子浓度、乙酸根浓度、2H-PFOA[F(CF_2)_6CHFCOOH]浓度和短链(C8)全氟羧酸(PFCAs)浓度的变化等作为指标,研究PFOA的厌氧可生物降解性.结果表明,活菌降解样中PFOA摩尔回收率由培养期初(3d)的101%±5%降至培养期末(250 d)的85.6%±3.9%,而氟离子浓度则由培养期初(3 d)的0.59 mg·L~(-1)±0.02 mg·L~(-1)增至培养期末(250 d)的0.63 mg·L~(-1)±0.02 mg·L~(-1),且检出了一定量的乙酸根、2H-PFOA和短链PFCAs,但是这却和其对照样中相应指标的变化类似,且不存在显著性差异.由此可见,尽管热力学计算结果表明还原脱氟产生的热量足够维持微生物生命活动,但在本研究的实验条件下却并没有发现PFOA可被生物降解的证据.     

Competitive effects and interactions during sorption of SMP fractions on activated carbon: response surface approach for visualization of sorption profiles

The objectives of this study were to investigate the significance of the effects and interactions for during competitive sorption of soluble microbial products (SMP). Batch experiments were conducted to assess the competitive sorption characteristics and individual affinity of glucose (carbohydrate) and bovine serum albumin (BSA) (protein) as two representative fractions of SMP. The influence of surface availability was investigated by using carbon particles with different particle sizes (5-75 μm, 75-850 μm, and 850-1000 μm) and different carbon amounts. Competitive effects and interactions were evaluated for each adsorbate and surface availability. Competitive sorption mechanisms were quantified in relation to surface affinity of the SMP fractions. Sorption capacity profiles of the SMP fractions at equilibrium were developed using second-degree polynomial models for the experimental data and compared with the estimates obtained from the modified Langmuir-like model which uses single parameter sorption data to estimate competitive sorption profiles of systems with two adsorbates. Adequacy limitations of the modified Langmuir-like model for each SMP fraction were evaluated based on the significance of the synergistic and antagonistic effects between the two SMP fractions and the carbon surface availability.     

栅藻LX1和雨生红球藻的胞外产物产生特性及其对藻细胞生长的影响

基于微藻在资源化大规模培养过程中,其胞外产物对藻细胞生长影响的不确定性,对比研究了两株高含油脂藻种,栅藻LX1（Scenedesmus sp.LX1）和雨生红球藻（Haematococcus pluvislis）的生长特征、胞外产物的产生特性,以及胞外产物对藻细胞生长的影响。研究结果表明,在相同培养条件下,栅藻LX1与雨生红球藻的内禀生长速率基本相当,分别为0.16和0.17 d-1。两株藻在不同生长期的胞外产物（以DOC值表征）产生速率不同,其中栅藻LX1胞外产物的对数期产生速率（1.4 mg·L-1·d-1）﹥稳定期后期产生速率（0.56 mg·L-1·d-1）﹥稳定期产生速率（0.48 mg·L-1·d-1）;雨生红球藻胞外产物的稳定期后期产生速率（2.3 mg·L-1·d-1）﹥稳定期产生速率（0.88 mg·L-1·d-1）﹥对数期产生速率（0.66 mg·L-1·d-1）。栅藻LX1胞外产物对其整个生长过程都有明显抑制;雨生红球藻胞外产物则在稳定期后期才对其生长产生明显抑制作用。