The changes in streamflow and sediment discharge in the middle reaches of the Yellow River are a focus. In this paper, based on the precipitation, streamflow and sediment discharge series data ...(1950-2008), the streamflow and sediment discharge variation and its impact on precipitation/response to human activities have been analysis. The results show that significant decreasing trends in annual streamflow and sediment discharge have existed since the late 1950s in the middle reaches of the Yellow River (P = 0.01). Change-point analyses further revealed that transition years existed and that abrupt decline in streamflow and sediment discharge began in 1985 and 1981, respectively, in the middle reaches of the Yellow River (P = 0.05). Adoption of conservation measures in the 1980s and 1990s corroborates the identified transition years. Double-mass curves of precipitation vs. streamflow (sediment) for the periods before and after the transition year show remarkable decreases in proportionality of streamflow (sediment) generation. Compared with the period before the transition year, cumulative streamflow and cumulative sediment discharge reduced respectively by 17.8% and 28% during 1985-2008, which was caused by human intervention, in the middle reaches of the Yellow River. It is, therefore, concluded that human activities occupied a dominant position and played a major role in the streamflow and sediment discharge reduction in the middle reaches of the Yellow River.
It is a novel idea to make steamed bread by adding potato flour into wheat flour considering the production and nutritional factors of potato. In this study, the influence of potato flour（0–35%） on ...dough rheology and quality of steamed bread were investigated. Potato flour addition significantly influenced the dough rheological properties and steamed bread quality, such as increased water absorption, the maximum gaseous release height, total volume of CO_2 and hardness, while decreased dough stability and specific volume of steamed bread. Moreover, correlation analysis suggested that dough height at the maximum development time, dough stability, water absorption and the phase tangent can be used for predicting the technological quality of steamed bread. Potato-wheat steamed bread had higher dietary fibre, ash content and antioxidant activity than those of wheat steamed bread. The estimated glycemic index decreased from 73.63（0%） to 60.01（35%）. Considering the sensory evaluation, the steamed bread with 20% potato flour is acceptable. In conclusion, adding appropriate quantity of potato flour to wheat flour for steamed bread production will not only maintain the technological quality, but also can improve the nutritional value of the steamed bread.
Reduced stream flow and increased sediment discharge are a major concern in the Yellow River basin of China, which supplies water for agriculture, industry and the growing populations located along ...the river. Similar concerns exist in the Wei River basin, which is the largest tributary of the Yellow River basin and comprises the highly eroded Loess Plateau. Better understanding of the drivers of stream flow and sediment discharge dynamics in the Wei River basin is needed for development of effective management strategies for the region and entire Yellow River basin. In this regard we analysed long-term trends for water and sediment discharge during the flood season in the Wei River basin, China. Stream flow and sediment discharge data for 1932 to 2008 from existing hydrological stations located in two subcatchments and at two points in the Wei River were analysed. Precipitation and air temperature data were analysed from corresponding meteorological stations. We identified change-points or transition years for the trends by the Pettitt method and, using double mass curves, we diagnosed whether they were caused by precipitation changes, human intervention, or both. We found significant decreasing trends for stream flow and sediment discharge during the flood season in both subcatchments and in the Wei River itself. Change-point analyses further revealed that transition years existed and that rapid decline in stream flow began in 1968 (P < 0.01), and that sediment discharge began in 1981 (P < 0.01) in the main river. In the two subcatchments, the transition years were 1985 (P < 0.01) and 1994 (P < 0.05) for water discharge, and 1978 and 1979 for sediment discharge (P < 0.05), respectively. The impact of precipitation or human activity on the reduction amount after the transition years was estimated by double mass curves of precipitation vs. stream flow (sediment). For reductions in stream flow and sediment discharge, the contribution rate of human activity was found to be 82.80 and 95.56%, respectively, and was significantly stronger than the contribution rate of precipitation. This evidence clearly suggests that, in the absence of significant decreases in precipitation, strategies for managing the region need to focus on human activities to control erosion without restricting stream flow.
Currently, the development of nitrogen (N) doped carbon based non-precious metal ORR catalysts has become one of the most attractive topics in low temperature fuel cells. Here, we demonstrate a green ...synthesis route of N-self-doped carbon materials by using eggs as N sources combining with iron sources and multi-walled carbon nanotubes (CE-Fe-MWNT). After carbonized, such hybrid materials possess an outstanding electrocatalytic activity towards ORR comparable to the commercial Pt/C catalyst in alkaline media, and both superior stability and fuel (methanol and CO) tolerance than the commercial Pt/C catalyst, which provide a promising alternative to noble metal catalysts by using abundant natural biological resources.
Pituitary stalk interruption syndrome (PSIS) is a rare congenital defect manifesting with varying degrees of pituitary hormone deficiency. The signs and symptoms of PSIS during the neonatal period ...and infancy are often overlooked and therefore diagnosis is delayed. The typical manifestations of PSIS can be detected by magnetic resonance imaging. Several genes in the Wnt, Notch and Shh signalling pathways related to hypothalamic‐pituitary development, such as PIT1, PROP1, LHX3/LHX4, PROKR2, OTX2, TGIF and HESX1, have been found to be associated with PSIS. Nevertheless, the aetiology in the majority of cases still remains unknown. In the present review, we provide an overview of clinical features of PSIS and summarise our current understanding of the underlying pathogenic mechanisms for this rare syndrome. Furthermore, we propose future research directions that may help our understanding of the aetiology of PSIS.
Financial Dampening WIELAND, JOHANNES F.; YANG, MU‐JEUNG
Journal of money, credit and banking,
February 2020, Letnik:
52, Številka:
1
Journal Article
Recenzirano
We propose a novel mechanism, “financial dampening,” whereby loan retrenchment by banks attenuates the effectiveness of monetary policy. The theory unifies an endogenous supply of illiquid local ...loans and risk sharing among subsidiaries of bank holding companies (BHCs). We derive an instrumental variable (IV) strategy that separates supply‐driven loan retrenchment from local loan demand by exploiting linkages through BHC internal capital markets across spatially separate BHC member banks. We estimate that retrenching banks increase loan supply substantially less in response to exogenous monetary policy rate reductions. This relative decline has persistent effects on local employment and thus provides a rationale for slow recoveries from financial distress.
The perfluorosulfonic acid (PFSA) polymer was introduced to improve the lifetime and performance of CNT-supported Pt catalysts. We demonstrated that Pt nano-particles can be produced well-dispersed ...on the CNT surfaces, and the catalytic activity and stability of the resulting composite catalyst was greatly enhanced with additional PFSA
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► Compared to carbon black, the carbon nanotube (CNT) has high chemical stability and unique mechanical property, which could effectively decrease the support degradation. ► The introduction of perfluorosulfonic acid (PFSA) polymer greatly improves dispersion of metal particles on inert CNT surfaces by enhancing metal-support interaction. ► The PFSA polymer can enhance the catalytic activity of Pt catalysts by increasing the triple phase boundary reaction zone. Most significantly, the PFSA offers a strong metal-support interaction as both a binder and a stabilizer for Pt nano-particles, which further improves the CNT supported catalyst lifetime.
To further improve lifetime and performance of carbon nanotube (CNT) supported Pt catalysts for proton exchange membrane fuel cells, perfluorosulfonic acid (PFSA) was introduced by a simple colloid route to functionalize Pt (PFSA-Pt/CNT) catalysts. Here the PFSA is available as a binder to tightly anchor Pt nano-particles onto the CNT surfaces, and as a proton conductor to increase the triple phase boundary zone of the catalysts. The prepared Pt nano-particles ranging from 2 to 5
nm in diameter are uniformly deposited on CNTs. A high catalytic activity of this novel composite catalyst was observed by both cyclic voltammetry and oxygen reduction reaction (ORR) measurements. The loss rate of the electrochemically active area of the PFSA-Pt/CNT catalyst decreases by a factor of two in comparison with that of the plain Pt/CNT catalyst. Meanwhile, a lower loss rate for the new catalyst was also observed by electrochemically-accelerated durability testing for the ORR activity. These results indicate that the stability of the new catalyst is significantly improved over that of the plain Pt/CNT catalyst by introduction of PFSA.
Spinel metal oxide with an extra crystalline phase is an active way to enhance the performance of the supercapacitor. Herein, a facile hydrothermal approach has been established for synthesizing ...nanocrystalline NiCo2O4 with an extra NiO phase material as the potential electrode for a supercapacitor. XRD analysis is executed to expose the crystalline environment and found to be dual phases ie. NiO and NiCo2O4. Further, the chemical environment of these phases is identified in FTIR, EDS, X-ray photoelectron spectroscopy, elemental mapping, and Raman analysis. The morphological analysis (SEM) of the material showed that the formation of tiny particulates aggregates become uniform in size, which consists of a nearly spherical structure. NiCo2O4–NiO showed a remarkable electrochemical performance in a 2 M potassium hydroxide. The maximum capacitance was achieved as 866 F/g at a sweep rate of 5 m V/s, which is quite higher than the normal pristine NiCo2O4. The material delivered a capacity retention of 85% over 5000 cycles. This high performance was attributed to the NiO phase in NiCo2O4 material inducing an additional charge at the boundary, prominent to synergistic effect and rapid electron and ion passage. Hence, overall, the superior performance with extra NiO phase could be beneficial for developing spinel metal oxide electrodes for battery-type supercapacitor applications.
•NiCo2O4 material with an extra NiO phase is an active way to enhance the performance of the energy storage supercapacitor for the first time.•NiCo2O4–NiO material synthesized via a facile hydrothermal approach had shown a higher capacitance of 866 F/g at 5 m V/s in a 2 M KOH electrolyte.•The material exhibits higher capacity and outstanding cycling retention of 85% was achieved over 5000 continuous cycles.•These NiO existence as an interior phase in NiCo2O4 designs plays a significant role in their electrochemical behavior for battery-type supercapacitor applications.
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