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941.
This paper proposes a novel mixed integer linear programming model to solve a supply chain network design problem. The proposed model deals with major issues for supply chains; product quality and cost. These issues are usually solved separately, but in this paper, we investigate effects of product quality on supply chain design and transportation flow. A trade-off between raw material quality, its purchasing and reprocessing costs was considered. Assuming decision maker (DM) wishes to work with a supplier which serves a low quality raw material; this raw material should be in need of reprocessing. To avoid the reprocessing costs, a supplier which serves a high quality raw material should be chosen but at this time the DM has to face a high purchasing cost. A supply chain network which consists of multiple suppliers, manufacturers, distribution centers and retailers is tried to be designed to accomplish aforementioned above trade-offs. The paper examines and discusses the relationship between product quality and supply chain design and offers several managerial insights.  相似文献   
942.
943.
Hyperpolarization is generated by dissolution dynamic nuclear polarization (d‐DNP) using a polymer‐based polarizing agent dubbed FLAP (filterable labeled agents for polarization). It consists of a thermo‐responsive poly(N‐isopropylacrylamide), also known as pNiPAM‐COOH, labeled with nitroxide radicals. The polymer powder is impregnated with an arbitrary solution of interest and frozen as is. Dissolution is followed by a simple filtration, leading to hyperpolarized solutions free from any contaminants. We demonstrated the use of FLAP to hyperpolarize partially deuterated water up to P(1H)=6 % with a long relaxation T1 >36 s characteristic of high purity. Water hyperpolarization can be transferred to drugs, metabolites, or proteins that are waiting in an NMR spectrometer, either by exchange of labile protons or through intermolecular Overhauser effects. We also show that FLAPs are suitable polarizing agents for 13C‐labeled metabolites such as pyruvate, acetate, and alanine.  相似文献   
944.
945.
A number of 1,2,4-oxadiazolone and mercapto nitro benzimidazole derivatives containing 1,2,4-oxadiazole and hydantoin moieties have been prepared, and their structures were identified by means of spectral/physical characteristics including X-ray diffraction data.  相似文献   
946.
In this work, we investigated for the first time the characteristics of (poly (3-hexylthiopene) and [6, 6]-phenyl C61-butyric acid methyl ester) (P3HT:PCBM) blends-based organic solar cell with 1.25?mg/mL boric-acid (H3BO3)-doped poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) layer which is irradiated under the 40 Gray (Gy) dose of gamma (γ) ray. Experimental results showed that the parameters of solar cell improved with exposure to low-dose gamma radiation. In particular, it has provided a significant improvement in short-circuit current density (Jsc) and power conversion efficiency (PCE). About 49% increase in PCE to 1.22% and 40% increase in Jsc to 6.28?mA/cm2 was obtained between the bare device and the device containing irradiated PEDOT:PSS:H3BO3. Also, it was determined that the H3BO3-doped PEDOT:PSS is more stable to temperature. More importantly, solar cell containing gamma-irradiated PEDOT:PSS:H3BO3 showed best performance comparing to conventional PEDOT:PSS-based cell.  相似文献   
947.
948.
949.
High-performance liquid chromatography (HPLC) with size exclusion (SEC) separation function was used to isolate and examine the molecular mass (MM) distributions and polydispersity of humic substances (HSs) and dissolved organic matter (DOM) from mineral soils and peats. The aim was to improve their detailed characterisation and to inform of their soil carbon (C) sequestration and environmental quality. This is the first study conducted in Lithuania in which HSs and DOM, separated from two soil types, have been used to characterise soil at the molecular level. The HPLC-SEC, as a separation method, was coupled with diode-array detection (DAD), thus enabling the separation of molecular fractions. Results showed that HPLC-SEC can be used to determine the MM of HSs in soil, provided that the relation between retention time and MM is known and a suitable method for fitting the HS peak is available. The UV-spectra analysis showed that DOM has a larger MM (Mw = 2439–3436 Da), which contains more aliphatic C. The HS fraction has a smaller MM (Mw = 2776 Da), with aromatic structures that reflect a higher aromaticity. Separated fractions had characteristic MMs of humic acid (HA) and fulvic acid (FA) and DOM. The HSs separated from peat samples were characterised by higher aromaticity, humification and stability. The HSs extracted from mineral soil samples showed a higher degradability level. The results also show the MM distribution and polydispersity of HS and DOM fractions (Mw/Mn = 1.009–1.252) are relatively homogenous in both soil types. Findings confirm that chromatographic and spectrometric parameters can be used for characterisation of both HSs and DOM, and for detecting changes in organic matter quality. Moreover, they can also be used for a further understanding the C-cycle and could be applied for enhancing soil C-sequestration and informing environmental quality management.  相似文献   
950.
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