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71.
Capturing value from design-based innovation presents firms with some challenges which only recently academic research has started addressing. Increasingly, firms operating within design-intensive industries collaborate with external designers rather than undertaking this activity in-house. This raises some appropriability issues, as firms would need to reap the benefits of innovation originating across organisational boundaries. To address this gap, we carried out a multiple case study with firms and design consultants based in Italy across several manufacturing sectors. Our evidence suggests the presence of appropriability mechanisms that are specific to design innovation. Intellectual property rights, although not very effective, are employed to establish ownership in the market. Firms also use lead-time advantages, investment in specific assets and the quality of craftsmanship depending on the industry. Across most sectors, establishing long-term relationships inspired by knowledge sharing and trust constitutes a key mechanism firms adopt to appropriate the benefits attached to collaboration with external designers.  相似文献   
72.
Relationships between flow distributions and mechanical opening in a single natural fracture are investigated in situ through field experiments, at a scale of about 1 m, in a granitic quarry. Experiments have been conducted at various injection flow-rates while the normal stress applied to the fracture was controlled by hydraulic flat jacks. Variations of the collected flow-rate (monitored through contiguous flow collectors distributed along the fracture periphery) with the injection pressure are fully reproducible. They show that the fracture opens only above a threshold pressure which increases with the externally applied stress. This threshold is non-zero with no applied flat jacks pressure which raises questions on the reliability of hydraulic jacking techniques for the measurement of the normal stress on preexisting fractures. It is shown that equivalent hydraulic aperture and mechanical opening are comparable only above a critical mean fracture opening estimated to be around 15–20 μm for the tested granite. For mean fracture openings smaller than this value, the standard time scale used for stress measurements distorts the results. It is also shown that channeling effects may control flow away from the injection hole so that the hydraulic jacking stress measurement technique may overestimate the mean normal stress acting on the fracture plane by as much as 4 MPa. It is concluded that hydraulic testing techniques for normal stress measurements should not include results from the fracture opening phase. Moreover, criteria should be established for validating results from the closing phase in order to demonstrate the absence of channelling effects. Finally, it is shown that, because of the elastic response of the rock, water injection in a fracture system decreases the interstitial pressure ahead of the increasing pressure front associated with the water flow.  相似文献   
73.
Graphene is regarded as the ultimate material for future flexible, high‐performance, and wearable electronics. Herein, a novel, robust, all‐green, highly reliable (yield ≥ 99%), and upscalable technology is reported for wearable applications comprising reduced graphene oxide (rGO) as the electroactive component in liquid‐gated transistors (LGTs). rGO is a formidable material for future flexible and wearable applications due to its easy processability, excellent surface reactivity, and large‐area coverage. A novel protocol is established toward the high‐yield fabrication of flexible rGO LGTs combining high robustness (>1.5 h of continuous operation) with state‐of‐the‐art performances, being similar to those of their rigid counterparts operated under liquid gating, including field‐effect mobility of ≈10?1 cm2 V?1 s?1 and transconductance of ≈25 µS. Permeable membranes have been proven crucial to operate flexible LGTs under mechanical stress with reduced amounts of solution (<20 µL). Our rGO LGTs are operated in artificial sweat exploiting two different layouts based on lateral‐flow paper fluidics. These approaches pave the road toward future real‐time tracking of perspiration via a simple and cost‐effective approach. The reported findings contribute to the robust and scalable production of novel graphene‐based flexible devices, whose features fulfill the requirements of wearable electronics.  相似文献   
74.
In the present investigation, fresh and dried tomato samples from markets and packinghouses located in Apulia region (southern Italy) were analysed for Alternaria toxins. All samples proved to be contaminated by tenuazonic acid (TeA); in particular, dried tomatoes were contaminated in the range 425–81,592 µg/kg, while fresh tomatoes were in the range 11–4560 µg/kg. The second most abundant toxin was alternariol monomethyl ether (AME), followed by tentoxin (TEN) and alternariol (AOH). Overall dried tomatoes were more contaminated than fresh ones, although this seemed not directly related to the presence of sodium chloride, utilized in the drying process. Five representative Alternaria isolates within those collected from samples proved to be one Alternaria arborescens (A215) and four Alternaria alternata. Within the latter species, one strain belonged to morphotype tenuissima (A216), and three to alternata (A214, A217 and A218). They were confirmed to produce TeA, AOH, and AME in vitro. This study demonstrates the possible risk for consumers’ health related to the consumption of contaminated fresh and dried tomatoes, and thus the need for suitable control strategies.  相似文献   
75.
76.
Thermotoga neapolitana is a hyperthermophilic eubacterium that produces hydrogen by sugar fermentation. A lab strain of T. neapolitana DSMZ 4359T maintained in a CO2-enriched atmosphere showed a stable increase of lactic acid production under capnophilic lactic fermentation (CLF) conditions. The genotypic comparison between the putative mutant (TN-CMut) and the original strain DSMZ 4359T (WT4359) revealed 88.1 (±2.4)% DNA homology. RiboPrint® and MALDI-TOF mass analyses support a genetic differentiation beyond subspecies level. The phenotypic characterization indicated a high correlation between the two strains, except for the lactic acid production. Under identical operating conditions, the lab mutant produced significantly more lactic acid than the parent strain without impairing the hydrogen yield. The highest divergence between TN-CMut and WT4359 was observed for fermentation of glucose or lactose at 80 °C. Based on these results, we propose that the lab strain is a new subspecies of the genus Thermotoga that is named T. neapolitana subsp. capnolactica with regards to its improved feature to produce lactic acid under capnophilic conditions.  相似文献   
77.
78.
We introduce a new fluorescence microscopy technique that maps the axial position of a fluorophore with subnanometer precision. The interference of the emission of fluorophores in proximity to a reflecting surface results in fringes in the fluorescence spectrum that provide a unique signature of the axial position of the fluorophore. The nanometer sensitivity is demonstrated by measuring the height of a fluorescein monolayer covering a 12-nm step etched in silicon dioxide. In addition, the separation between fluorophores attached to the top or the bottom layer in a lipid bilayer film is determined. We further discuss extension of this microscopy technique to provide resolution of multiple layers spaced as closely as 10 nm for sparse systems.  相似文献   
79.
BACKGROUND: Data on the association of human papillomavirus (HPV) infection with extragenital Bowen's disease are very scarce. OBJECTIVE: To evaluate the prevalence of HPV infection in extragenital Bowen's disease showing histologically a number of koilocytes in the lesional epidermis, we studied formalin-fixed, paraffin-embedded tissues of 9 such cases. METHODS: HPV DNA was studied in such samples by the polymerase chain reaction (PCR) and in situ hybridization. RESULTS: Despite negative results with in situ hybridization, the PCR with HPV type 33 primer detected the presence of virus DNA in 2 out of 9 cases. CONCLUSION: As far as we know, this is the first report of the detection of HPV type 33 DNA in the lesional skin of extragenital Bowen's disease. The prevalence of HPV infection in extragenital Bowen's disease may be higher than expected, especially in cases histologically showing many koilocytes in the lesional epidermis.  相似文献   
80.
Diffusional mixing of a granular system differs from that of fluids systems in many respects, being the most important, the lack of particulate motion equivalent to molecular diffusion; i.e. there is no relative movement of particles without an energy input. If we can design a mixer that gives the grains the necessary energy to flow and, at the same time, changes randomly their velocities, we will, in principle, simulate the diffusive movements of molecules in a liquid or gas. Based on these ideas, we study experimentally the 2D flow of a granular material (discs) through a dispersive medium: a Galton board. It consists on a regular array of obstacles that deflect the discs in random directions so they fall by gravity. In this work we present some preliminary results.  相似文献   
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