New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<s...New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<sub>2</sub>O (1∙2H<sub>2</sub>O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)<sub>2</sub>∙6H<sub>2</sub>O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H<sub>2</sub>O. Compound 1∙2H<sub>2</sub>O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H<sub>2</sub>O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H<sub>2</sub>O displayed moderate activity (10 ∙2H<sub>2</sub>O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus).展开更多
New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<s...New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<sub>2</sub>O (1∙2H<sub>2</sub>O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)<sub>2</sub>∙6H<sub>2</sub>O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H<sub>2</sub>O. Compound 1∙2H<sub>2</sub>O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H<sub>2</sub>O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H<sub>2</sub>O displayed moderate activity (10 ∙2H<sub>2</sub>O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus).展开更多
Considering the frequent use of netupitant in polytherapy,the elucidation of its oxidative metabolization pattern is of major importance.However,there is a lack of published research on the redox behavior of this nove...Considering the frequent use of netupitant in polytherapy,the elucidation of its oxidative metabolization pattern is of major importance.However,there is a lack of published research on the redox behavior of this novel neurokinin-1 receptor antagonist.Therefore,this study was performed to simulate the intensive hepatic biotransformation of netupitant using an electrochemically driven method.Most of the known enzyme-mediated reactions occurring in the liver(i.e.,N-dealkylation,hydroxylation,and Noxidation)were successfully mimicked by the electrolytic cell using a boron-doped diamond working electrode.The products were separated by reversed-phase high-performance liquid chromatography and identified by high-resolution mass spectrometry.Aside from its ability to pinpoint formerly unknown metabolites that could be responsible for the known side effects of netupitant or connected with any new perspective concerning future therapeutic indications,this electrochemical process also represents a facile alternative for the synthesis of oxidation products for further in vitro and in vivo studies.展开更多
Carbon fiber-reinforced thermoplastics (CFRP) have excellent specific strength and rigidity, which has made them a popular material for lightweight construction. The growing demand for fiber-reinforced plastics (FRP) ...Carbon fiber-reinforced thermoplastics (CFRP) have excellent specific strength and rigidity, which has made them a popular material for lightweight construction. The growing demand for fiber-reinforced plastics (FRP) leads to the problem of the sustainable handling of FRP at the end of their life cycle. The aim of the research project was to gain knowledge about the shredding of FRP concerning the optimal machine and process design of the shredding process and the possible formation of harmful, inhalable dust fractions and WHO fibers. Toxicity should be investigated at the cellular level. The investigated shredding parameters influence the amount and length of fiber dust produced, both when shredding with a cutting mill and when shredding with a single-shaft shredder. In all investigations, an increasing rotational speed leads to an increase in the fiber dust mass or the fiber concentration. The proportion of short, respirable fibers increases, but raising the speed does not lead to a further, significant shortening of the fibers. A reduction in feedstock size leads to a slightly reduced mass of fiber dust in the ground material. A reduction in the screen size also leads to an increase in fiber dust mass and concentration. There was no recognizable cytotoxicity in the relevant concentration range up to 500 μg/cm<sup>2</sup> and no significant induction of cell migration. This indicates minor flammable effects of the dust formed after inhalation. The biological data indicate that the WHO fibers produced by shredding are only a minor health hazard. Formally, the detected carbon fiber (CF) fragments meet the fiber definition of the legislator. However, carbon fibers currently have no specific limit value.展开更多
System logs record detailed information about system operation and areimportant for analyzing the system's operational status and performance. Rapidand accurate detection of system anomalies is of great significan...System logs record detailed information about system operation and areimportant for analyzing the system's operational status and performance. Rapidand accurate detection of system anomalies is of great significance to ensure system stability. However, large-scale distributed systems are becoming more andmore complex, and the number of system logs gradually increases, which bringschallenges to analyze system logs. Some recent studies show that logs can beunstable due to the evolution of log statements and noise introduced by log collection and parsing. Moreover, deep learning-based detection methods take a longtime to train models. Therefore, to reduce the computational cost and avoid loginstability we propose a new Word2Vec-based log unsupervised anomaly detection method (LogUAD). LogUAD does not require a log parsing step and takesoriginal log messages as input to avoid the noise. LogUAD uses Word2Vec togenerate word vectors and generates weighted log sequence feature vectors withTF-IDF to handle the evolution of log statements. At last, a computationally effi-cient unsupervised clustering is exploited to detect the anomaly. We conductedextensive experiments on the public dataset from Blue Gene/L (BGL). Experimental results show that the F1-score of LogUAD can be improved by 67.25%compared to LogCluster.展开更多
CONSPECTUS:The energy density of the ubiquitous lithium-ion batteries is rapidly approaching its theoretical limit.To go beyond,a promising strategy is the replacement of conventional intercalation-type materials with...CONSPECTUS:The energy density of the ubiquitous lithium-ion batteries is rapidly approaching its theoretical limit.To go beyond,a promising strategy is the replacement of conventional intercalation-type materials with conversion-type materials possessing substantially higher capacities.Among the conversion-type cathode materials,sulfur constitutes a cost-effective and earth-abundant element with a high theoretical capacity that has a potential to be game-changing,especially within an emerging solid-state battery configuration.Employment of nonflammable solid electrolytes that improves battery safety and boosts the energy density,as lithium metal anodes are also viable.The long-standing inherent problem of conventional lithium−sulfur batteries,arising from the reaction intermediates dissolved in liquid electrolytes,can be eliminated with inorganic solid ion conductors.In particular,the highly conducting and easily processable lithium-thiophosphates have successfully enabled the lab-scale solid-state lithium−sulfur cells to achieve close-to-theoretical capacities.For applications requiring safe,energy-dense,lightweight batteries,solid-state lithium−sulfur batteries are an ideal choice that could surpass conventional lithium-ion batteries.展开更多
Chemically modified pullulan was evaluated for its sorption efficiency and selectivity to remove cadmium(Cd) from spiked high-hardness groundwater(GW). Pullulan esterified with succinic anhydride using dimethylami...Chemically modified pullulan was evaluated for its sorption efficiency and selectivity to remove cadmium(Cd) from spiked high-hardness groundwater(GW). Pullulan esterified with succinic anhydride using dimethylaminopyridine showed a fairly high degree of substitution value as confirmed by1 H NMR spectroscopy. Pullulan succinate(Pull-Suc) was converted into the sodium salt(Pull-Suc-Na). The effect of contact time(5–200 min) and p H(2–8) on Cd-uptake by the sorbent(Pull-Suc-Na) was investigated. The sorbent showed more than 90% Cd-removal in first 15 min from distilled water(DW) and GW solution,respectively. Comparison of Pull-Suc-Na with other polysaccharidal sorbents suggested its high efficiency(DW 476.2 mg/g and GW 454.5 mg/g) and selectivity for the removal of Cd by an ion exchange mechanism, which is further supported by the negative Gibbs free energy values calculated from Langmuir isotherms. A Langmuir isotherm kinetic model provided the best fit for the sorption of Cd using Pull-Suc-Na. The sorbent showed a negligible decrease in Cd-uptake over three regeneration cycles. The thermal stability testing of the sorbents indicated that Pull-Suc-Na(sorbent) is more stable than Pull-Suc.展开更多
A double holmium-silver sulfate was obtained for the first time.The temperature intervals for the formation and stability of the compound were determined by differential scanning calorimetry.The crystal structure of A...A double holmium-silver sulfate was obtained for the first time.The temperature intervals for the formation and stability of the compound were determined by differential scanning calorimetry.The crystal structure of AgHo(SO_(4))_(2)was determined by Rietveld method.The X-ray diffraction(XRD)analysis showed that the compound crystallizes in the monoclinic syngony,space group P2_1/m,with the unit cell parameters a=4.71751(4)A,b=6.84940(6)A and c=9.89528(9)A,β=95.1466(4)·,V=318.448(5)A^(3),Z=2,R_B=1.55%,T=303 K.Two types of sulfate tetrahedra were found in the structure,which significantly affected the spectral properties in the infrared range.In the temperature range of 143-703 K,a negative thermal expansion along the b direction accompanied by a positive thermal expansion along the a and c directions was observed.It was established that negative thermal expansion is the result of the deformation of sulfate tetrahedra,which is affected by the movement of holmium and silver atoms.The excitation in the blue spectral range(457.9 nm)produces a luminescence in light blue(489 nm),green(545 nm)and red(654 nm)spectral ranges,and the latter two were of comparable intensity that is favorable for WLED sources.The observed luminescent band distribution is ascribed to the specific crystal field at Ho^(3+)ion sites rather than a variation of radiationless probability.展开更多
All-cis-hexafluoro-and all-cis-pentafluoro-cyclohexane(PFCH)derivatives are new kinds of materials,the structures and properties of which are dominated by the highly dipolar Janus-face motif.Here,we report on the effe...All-cis-hexafluoro-and all-cis-pentafluoro-cyclohexane(PFCH)derivatives are new kinds of materials,the structures and properties of which are dominated by the highly dipolar Janus-face motif.Here,we report on the effects of integrating the PFCH groups into self-assembled monolayers(SAMs)of alkanethiolates on Au(111).Monolayers with an odd(eleven)and even(twelve)number of methylene groups were characterized in detail by several complementary experimental tools,supported by theoretical calculations.Surprisingly,all the data show a high similarity of both kinds of monolayers,nearly lacking the typically observed odd-even effects.These new monolayers have a packing density about 1/3 lower than that of non-substituted alkanethiolate monolayers,caused by the bulkiness of the PFCH moieties.The orientations of the PFCH groups and the alkyl chains could be determined independently,suggesting a conformation similar to the one found in the solid state structure of an analogous compound.Although in the SAMs the PFCH groups are slightly tilted away from the surface normal with the axial fluorine atoms pointing downwards,most of the dipole moments of the group remain oriented parallel to the surface,which is a unique feature for a SAM system.The consequences are much lower water contact angles compared to other partly fluorinated SAMs as well as rather moderate work function values.The interaction between the terminal PFCH moieties results in an enhanced stability of the PFCH-decorated SAMs toward exchange reaction with potential molecular substituents in spite of the lower packing density of these films.展开更多
文摘New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<sub>2</sub>O (1∙2H<sub>2</sub>O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)<sub>2</sub>∙6H<sub>2</sub>O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H<sub>2</sub>O. Compound 1∙2H<sub>2</sub>O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H<sub>2</sub>O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H<sub>2</sub>O displayed moderate activity (10 ∙2H<sub>2</sub>O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus).
文摘New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<sub>2</sub>O (1∙2H<sub>2</sub>O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)<sub>2</sub>∙6H<sub>2</sub>O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H<sub>2</sub>O. Compound 1∙2H<sub>2</sub>O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H<sub>2</sub>O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H<sub>2</sub>O displayed moderate activity (10 ∙2H<sub>2</sub>O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus).
基金The authors gratefully acknowledged the financial support for part of this work by the German Research Foundation(DFG,Grant No.:KA 1093/7-2,Bonn,Germany)as well as Iuliu Hațieganu University(Internal Grant No.:5200/19/01.03.2017)a grant of the Romanian Ministry of Education and Research,CCCDI-UEFISCDI(Project No.:PNe-Ⅲ-P2-2.1-PED-2019-5473)within PNCDIⅢ.
文摘Considering the frequent use of netupitant in polytherapy,the elucidation of its oxidative metabolization pattern is of major importance.However,there is a lack of published research on the redox behavior of this novel neurokinin-1 receptor antagonist.Therefore,this study was performed to simulate the intensive hepatic biotransformation of netupitant using an electrochemically driven method.Most of the known enzyme-mediated reactions occurring in the liver(i.e.,N-dealkylation,hydroxylation,and Noxidation)were successfully mimicked by the electrolytic cell using a boron-doped diamond working electrode.The products were separated by reversed-phase high-performance liquid chromatography and identified by high-resolution mass spectrometry.Aside from its ability to pinpoint formerly unknown metabolites that could be responsible for the known side effects of netupitant or connected with any new perspective concerning future therapeutic indications,this electrochemical process also represents a facile alternative for the synthesis of oxidation products for further in vitro and in vivo studies.
文摘Carbon fiber-reinforced thermoplastics (CFRP) have excellent specific strength and rigidity, which has made them a popular material for lightweight construction. The growing demand for fiber-reinforced plastics (FRP) leads to the problem of the sustainable handling of FRP at the end of their life cycle. The aim of the research project was to gain knowledge about the shredding of FRP concerning the optimal machine and process design of the shredding process and the possible formation of harmful, inhalable dust fractions and WHO fibers. Toxicity should be investigated at the cellular level. The investigated shredding parameters influence the amount and length of fiber dust produced, both when shredding with a cutting mill and when shredding with a single-shaft shredder. In all investigations, an increasing rotational speed leads to an increase in the fiber dust mass or the fiber concentration. The proportion of short, respirable fibers increases, but raising the speed does not lead to a further, significant shortening of the fibers. A reduction in feedstock size leads to a slightly reduced mass of fiber dust in the ground material. A reduction in the screen size also leads to an increase in fiber dust mass and concentration. There was no recognizable cytotoxicity in the relevant concentration range up to 500 μg/cm<sup>2</sup> and no significant induction of cell migration. This indicates minor flammable effects of the dust formed after inhalation. The biological data indicate that the WHO fibers produced by shredding are only a minor health hazard. Formally, the detected carbon fiber (CF) fragments meet the fiber definition of the legislator. However, carbon fibers currently have no specific limit value.
基金funded by the Researchers Supporting Project No.(RSP.2021/102)King Saud University,Riyadh,Saudi ArabiaThis work was supported in part by the National Natural Science Foundation of China under Grant 61802030+2 种基金Natural Science Foundation of Hunan Province under Grant 2020JJ5602the Research Foundation of Education Bureau of Hunan Province under Grant 19B005the International Cooperative Project for“Double First-Class”,CSUST under Grant 2018IC24.
文摘System logs record detailed information about system operation and areimportant for analyzing the system's operational status and performance. Rapidand accurate detection of system anomalies is of great significance to ensure system stability. However, large-scale distributed systems are becoming more andmore complex, and the number of system logs gradually increases, which bringschallenges to analyze system logs. Some recent studies show that logs can beunstable due to the evolution of log statements and noise introduced by log collection and parsing. Moreover, deep learning-based detection methods take a longtime to train models. Therefore, to reduce the computational cost and avoid loginstability we propose a new Word2Vec-based log unsupervised anomaly detection method (LogUAD). LogUAD does not require a log parsing step and takesoriginal log messages as input to avoid the noise. LogUAD uses Word2Vec togenerate word vectors and generates weighted log sequence feature vectors withTF-IDF to handle the evolution of log statements. At last, a computationally effi-cient unsupervised clustering is exploited to detect the anomaly. We conductedextensive experiments on the public dataset from Blue Gene/L (BGL). Experimental results show that the F1-score of LogUAD can be improved by 67.25%compared to LogCluster.
基金The research that led to this work was supported by the Federal Ministry of Education and Research(BMBF)within the project LISZUBA under grant number of 03XP0115AS.O.acknowledges financial support from the JSPS KAKENHI Grant Number JP 21K14720.
文摘CONSPECTUS:The energy density of the ubiquitous lithium-ion batteries is rapidly approaching its theoretical limit.To go beyond,a promising strategy is the replacement of conventional intercalation-type materials with conversion-type materials possessing substantially higher capacities.Among the conversion-type cathode materials,sulfur constitutes a cost-effective and earth-abundant element with a high theoretical capacity that has a potential to be game-changing,especially within an emerging solid-state battery configuration.Employment of nonflammable solid electrolytes that improves battery safety and boosts the energy density,as lithium metal anodes are also viable.The long-standing inherent problem of conventional lithium−sulfur batteries,arising from the reaction intermediates dissolved in liquid electrolytes,can be eliminated with inorganic solid ion conductors.In particular,the highly conducting and easily processable lithium-thiophosphates have successfully enabled the lab-scale solid-state lithium−sulfur cells to achieve close-to-theoretical capacities.For applications requiring safe,energy-dense,lightweight batteries,solid-state lithium−sulfur batteries are an ideal choice that could surpass conventional lithium-ion batteries.
基金the Higher Education Commission, Pakistan, for funding under the scheme "HEC Indigenous 5000 Fellowships" with grant number PIN 074-1392-Ps4-584
文摘Chemically modified pullulan was evaluated for its sorption efficiency and selectivity to remove cadmium(Cd) from spiked high-hardness groundwater(GW). Pullulan esterified with succinic anhydride using dimethylaminopyridine showed a fairly high degree of substitution value as confirmed by1 H NMR spectroscopy. Pullulan succinate(Pull-Suc) was converted into the sodium salt(Pull-Suc-Na). The effect of contact time(5–200 min) and p H(2–8) on Cd-uptake by the sorbent(Pull-Suc-Na) was investigated. The sorbent showed more than 90% Cd-removal in first 15 min from distilled water(DW) and GW solution,respectively. Comparison of Pull-Suc-Na with other polysaccharidal sorbents suggested its high efficiency(DW 476.2 mg/g and GW 454.5 mg/g) and selectivity for the removal of Cd by an ion exchange mechanism, which is further supported by the negative Gibbs free energy values calculated from Langmuir isotherms. A Langmuir isotherm kinetic model provided the best fit for the sorption of Cd using Pull-Suc-Na. The sorbent showed a negligible decrease in Cd-uptake over three regeneration cycles. The thermal stability testing of the sorbents indicated that Pull-Suc-Na(sorbent) is more stable than Pull-Suc.
基金the Russian Foundation for Basic Research(Nos.18-02-00754 and 18-32-20011)the National Scientific Foundations of China(No.11974360)+1 种基金the Russian Science Foundation(No.19-42-02003,in the part of conceptualization)Basic Project of the Ministry of Science of the Russian Federation in part of XRD,luminescent and Raman studies。
文摘A double holmium-silver sulfate was obtained for the first time.The temperature intervals for the formation and stability of the compound were determined by differential scanning calorimetry.The crystal structure of AgHo(SO_(4))_(2)was determined by Rietveld method.The X-ray diffraction(XRD)analysis showed that the compound crystallizes in the monoclinic syngony,space group P2_1/m,with the unit cell parameters a=4.71751(4)A,b=6.84940(6)A and c=9.89528(9)A,β=95.1466(4)·,V=318.448(5)A^(3),Z=2,R_B=1.55%,T=303 K.Two types of sulfate tetrahedra were found in the structure,which significantly affected the spectral properties in the infrared range.In the temperature range of 143-703 K,a negative thermal expansion along the b direction accompanied by a positive thermal expansion along the a and c directions was observed.It was established that negative thermal expansion is the result of the deformation of sulfate tetrahedra,which is affected by the movement of holmium and silver atoms.The excitation in the blue spectral range(457.9 nm)produces a luminescence in light blue(489 nm),green(545 nm)and red(654 nm)spectral ranges,and the latter two were of comparable intensity that is favorable for WLED sources.The observed luminescent band distribution is ascribed to the specific crystal field at Ho^(3+)ion sites rather than a variation of radiationless probability.
文摘All-cis-hexafluoro-and all-cis-pentafluoro-cyclohexane(PFCH)derivatives are new kinds of materials,the structures and properties of which are dominated by the highly dipolar Janus-face motif.Here,we report on the effects of integrating the PFCH groups into self-assembled monolayers(SAMs)of alkanethiolates on Au(111).Monolayers with an odd(eleven)and even(twelve)number of methylene groups were characterized in detail by several complementary experimental tools,supported by theoretical calculations.Surprisingly,all the data show a high similarity of both kinds of monolayers,nearly lacking the typically observed odd-even effects.These new monolayers have a packing density about 1/3 lower than that of non-substituted alkanethiolate monolayers,caused by the bulkiness of the PFCH moieties.The orientations of the PFCH groups and the alkyl chains could be determined independently,suggesting a conformation similar to the one found in the solid state structure of an analogous compound.Although in the SAMs the PFCH groups are slightly tilted away from the surface normal with the axial fluorine atoms pointing downwards,most of the dipole moments of the group remain oriented parallel to the surface,which is a unique feature for a SAM system.The consequences are much lower water contact angles compared to other partly fluorinated SAMs as well as rather moderate work function values.The interaction between the terminal PFCH moieties results in an enhanced stability of the PFCH-decorated SAMs toward exchange reaction with potential molecular substituents in spite of the lower packing density of these films.